Dublin City Council
January 9, 2024

January 09, 2024 Dublin City Council Regular Meeting Agenda 1 COUNCILMEMBERS City Council Chamber
Melissa Hernandez, Mayor Dublin Civic Center
Dr. Sherry Hu, Vice Mayor 100 Civic Plaza
Jean Josey, Councilmember Dublin, CA 94568
Michael McCorriston, Councilmember www.dublin.ca.gov
Kashef Qaadri, Councilmember
Regular Meeting of the

DUBLIN CITY COUNCIL
Tuesday, January 9, 2024 Location: City Council Chamber 100 Civic Plaza
Dublin, CA 94568
Regular Meeting 7:00 PM
Additional Meeting Procedures
This City Council meeting will be broadcast live on Comcast T.V. channel 28 beginning at 7:00 p.m. This meeting will also be livestreamed at www.tv30.org and on the City’s website at: https://dublin.ca.gov/ccmeetings For the convenience of the City and as a courtesy to the public, members of the public who wish to offer comments electronically have the option of giving public comment via Zoom, subject to the following procedures:
□ Fill out an online speaker slip available at www.dublin.ca.gov. The speaker slip will be made available at 10:00 a.m. on Tuesday, January 9, 2024. Upon submission, you will receive Zoom link information from the City Clerk.

Speakers slips will be accepted until the staff presentation ends, or until the public comment period on non-agenda items is closed.
□ Once connected to the Zoom platform using the Zoom link information from the City Clerk, the public speaker will be added to the Zoom webinar as an attendee and muted. The speaker will be able to observe the meeting from the Zoom platform.
□ When the agenda item upon which the individual would like to comment is addressed, the City Clerk will announce the speaker in the meeting when it is their time to give public comment. The speaker will then be unmuted to give public comment via Zoom.
□ Technical difficulties may occur that make the option unavailable, and, in such event, the meeting will continue despite the inability to provide the option.
1 January 09, 2024 Dublin City Council Regular Meeting Agenda 2

1. CALL TO ORDER

2. PLEDGE OF ALLEGIANCE

3. PRESENTATIONS AND PROCLAMATIONS

3.1 Recognition of Centenarian Zainul Abedin Syed
The City Council will present a certificate to Centenarian Zainul Abedin Syed recognizing the milestone of reaching 100 years of life. Mr. Syed was born on November 23, 1923 and turned 100 on November 23, 2023. The City Council asked Staff to invite Mr. Syed to be recognized under Item 9 on December 5, 2023.

STAFF RECOMMENDATION:

Present the certificate.

Staff Report
Attachment 1 - Certificate of Recognition

3.2 2023 Sponsor Recognition
The City Council will recognize sponsors who contributed to City events, programs, and facilities in 2023.

STAFF RECOMMENDATION:

Recognize the 2023 sponsors.

Staff Report
Attachment 1 - 2023 City of Dublin Sponsor List
Item 3.2 – PowerPoint Presentation

3.3 Recognition of the 2023 “Deck the Homes” Holiday Home Decorating Contest Winners
The City Council will receive a presentation on the 2023 “Deck the Homes” Holiday Home Decorating Contest and present Certificates of Recognition to the winners.

STAFF RECOMMENDATION:

Present Certificate of Recognition to the 2023 “Deck the Homes” Holiday Home Decorating Contest winners.

Staff Report
Attachment 1 - 2023 Holiday Home Decorating Contest Winners Attachment 2 - 2023 Home Holiday Decorating Contest Flyer Item 3.3 - PowerPoint Presentation

4. PUBLIC COMMENT
At this time, the public is permitted to address the City Council on non-agendized items.

Please step to the podium and clearly state your name for the record. COMMENTS SHOULD NOT EXCEED THREE (3) MINUTES. In accordance with State Law, no action or discussion may take place on any item not appearing on the posted agenda. The Council may respond to statements made or questions asked, or may request Staff to report back at a future meeting concerning the matter. Any member of the public may contact the City Clerk’s Office related to the proper procedure to place an item on a future City Council agenda. The exceptions under which the City Council MAY discuss and/or take action on items not appearing on the agenda are contained in Government Code Section 54954.2(b)(1)(2)(3).
2 January 09, 2024 Dublin City Council Regular Meeting Agenda 3

5. CONSENT CALENDAR
Consent Calendar items are typically non-controversial in nature and are considered for approval by the City Council with one single action. Members of the audience, Staff or the City Council who would like an item removed from the Consent Calendar for purposes of public input may request the Mayor to remove the item.

5.1 Approval of the December 19, 2023 Regular City Council Meeting Minutes The City Council will consider approval of the minutes of the December 19, 2023 Regular City Council Meeting.

STAFF RECOMMENDATION:

Approve the minutes of the December 19, 2023 Regular City Council Meeting.

Staff Report
Attachment 1 - December 19, 2023 Regular City Council Meeting Minutes

5.2 Annual Proclamation
The City Council will review the Official List of Proclamations and consider approval of the Annual Proclamation.

STAFF RECOMMENDATION:

Accept the Official List of Proclamations and approve the Annual Proclamation.

Staff Report
Attachment 1 - Official List of Proclamations
Attachment 2 - City of Dublin Annual Proclamation

5.3 Mayor’s Appointments to Heritage and Cultural Arts Commission Unscheduled Vacancy and Parks and Community Services Commission Alternate Unscheduled Vacancy
The City Council will consider the Mayor’s appointments to fill an unscheduled vacancy on the Heritage and Cultural Arts Commission and an alternate unscheduled vacancy on the Parks and Community Services Commission.

STAFF RECOMMENDATION:

Confirm the Mayor’s appointments of Darren Phillips to the Heritage and Cultural Arts Commission for the remainder of a term ending December 2026 and Eric Nielsen as an alternate on the Parks and Community Services Commission for the remainder of a term ending December 2024.

Staff Report
Attachment 1 - Applications for the Heritage and Cultural Arts Commission Attachment 2 - Applications for Parks and Community Services Commission

5.4 Adoption of the Tri-Valley Hazard Mitigation Plan
The City Council will consider adoption of the Tri-Valley Hazard Mitigation Plan. The Plan includes a thorough hazard risk assessment, disaster mitigation priorities, and subsequent mitigation actions and projects for the cities of Dublin, Livermore, and Pleasanton, and Dublin San Ramon Services District.

STAFF RECOMMENDATION:

Adopt the Resolution Approving in its Entirety Volume I and the Relevant Portions of Volume II Including the Introduction, City of Dublin Annex, and Appendices of the TriValley Hazard Mitigation Plan.

Staff Report
3 January 09, 2024 Dublin City Council Regular Meeting Agenda 4 Attachment 1 - Resolution Approving in its Entirety Volume I and the Relevant Portions of Volume II Including the Introduction, City of Dublin Annex, and Appendices of the TriValley Hazard Mitigation Plan Attachment 2 - Exhibit A to the Resolution - Tri-Valley Hazard Mitigation Plan Attachment 3 - Cal OES Letter dated October 31, 2023
Attachment 4 - FEMA Letter dated December 15, 2023

5.5 2024 Storm Drain Art Selection
The City Council will consider a recommendation from the Heritage and Cultural Arts Commission for artwork to be painted on 20 storm drain inlets in spring 2024.

STAFF RECOMMENDATION:

Approve the Heritage and Cultural Arts Commission’s recommendations for the 2024 Storm Drain Art Program.

Staff Report
Attachment 1 - Design Proposals from Recommended Artists Attachment 2 - Call for Artists Storm Drain Art 2024

5.6 Change Order No. 2 to the Amended and Restated Energy Services Contract with Engie Services U.S. Inc.

The City Council will consider approving a second change order to the Amended and Restated Energy Services Contract for Operation and Maintenance with Engie Services U.S. Inc. (formerly OpTerra Energy Services, Inc.) to extend the contract term and add funding for photovoltaic system equipment operations, monitoring, maintenance, repair, replacement, and inspection services.

STAFF RECOMMENDATION:

Adopt the Resolution Approving Change Order No. 2 to the Amended and Restated Energy Services Contract for Operations and Maintenance with Engie Services U.S. Inc. and approve the budget change.

Staff Report
Attachment 1 - Resolution Approving Change Order No. 2 to the Amended and Restated Energy Services Contract for Operations and Maintenance with Engie Services U.S. Inc.

Attachment 2 - Exhibit A to the Resolution - Change Order No.2 to the Amended and Restated Energy Services Contract
Attachment 3 - Change Order No. 01 and Amended and Restated Energy Services Contract for Operation and Maintenance
Attachment 4 - Budget Change Form

6. PUBLIC HEARING

6.1 Amendment to the Dublin Municipal Code Inclusionary Zoning Regulations (Chapter

8.68), Adopting a Methodology for Determining Affordable Housing In-Lieu Fees and Adopting Non-Residential Development Affordable Housing Impact Fees (PLPA2023-00032) The City Council’s Two-Year Strategic Plan includes a review of the Inclusionary Zoning Regulations (Dublin Municipal Code Chapter 8.68), Affordable Housing In-Lieu Fee, and Non-Residential Development Affordable Housing Impact Fee (aka “Commercial Linkage Fee”). Staff and the City’s consultant, Economic and Planning Systems, prepared an Affordable Housing In-Lieu Fee Feasibility Study and a Commercial Linkage Fee Nexus Study to address the Strategic Plan objectives. The City Council received informational 4 January 09, 2024 Dublin City Council Regular Meeting Agenda 5 reports on August 15, 2023, and September 19, 2023, and directed Staff to prepare amendments to the Inclusionary Zoning Regulations, Affordable Housing In-Lieu Fee, and Non-Residential Development Affordable Housing Impact Fee programs to ensure they align with the economics of developing affordable housing and the City Council’s priorities. Staff has prepared the updates to these programs. The City Council will hold a Public Hearing to consider adopting the amendments to these programs.

STAFF RECOMMENDATION:

Conduct the public hearing, deliberate, and take the following actions: 1) waive the reading and INTRODUCE the Ordinance Approving Amendments to Dublin Municipal Code Chapter 8.68 (Inclusionary Zoning Regulations); 2) Adopt the Resolution Establishing the Methodology for Determining the Affordable Housing In-Lieu Fee for Future Residential Units Subject to the City of Dublin Inclusionary Zoning Regulations; and 3) Adopt the Resolution Approving the Non-Residential Development Affordable Housing Impact Fees.

Staff Report
Attachment 1 - Ordinance Approving Amendments to Dublin Municipal Code Chapter

8.68 (Inclusionary Zoning Regulations)
Attachment 2 - Resolution Establishing the Methodology for Determining the Affordable Housing In-Lieu Fee for Future Residential Units Subject to the City of Dublin Inclusionary Zoning Regulations
Attachment 3 - Exhibit A to the Resolution - Inclusionary Housing Feasibility Report dated December 7, 2023
Attachment 4 - Resolution Approving the Non-Residential Development Affordable Housing Impact Fees
Attachment 5 - Exhibit A to the Resolution - Commercial Linkage Fee Nexus Study dated October 27, 2023
Attachment 6 - Redlined Version of Amendment to Inclusionary Zoning Regulations Attachment 7 - City Council Staff Report dated August 15, 2023 Attachment 8 - City Council Staff Report dated September 19, 2023 Attachment 9 - Planning Commission Resolution 23- 12 Recommending City Council Approval of Amendments to Dublin Municipal Code Chapter 8.68 (Inclusionary Zoning Regulations)
Item 6.1 - City PowerPoint Presentation
Item 6.1 - EPS PowerPoint Presentation

6.2 Downtown Dublin Specific Plan Amendments – Parking Requirements (PLPA-2023- 00019)
The City Council will consider amendments to the Downtown Dublin Specific Plan to eliminate parking requirements in the Downtown. The proposed amendments implement recent changes in state law and the recommendations of the Urban Land Institute. They also extend the elimination of parking requirements beyond the state-required one-halfmile radius of the BART station to include all properties within the Downtown Dublin Specific Plan area.

STAFF RECOMMENDATION:

Conduct the public hearing, deliberate, and adopt the Resolution Amending the Downtown Dublin Specific Plan to Eliminate Parking Requirements in the Retail District, Transit-Oriented District, and Village Parkway District.

Staff Report
5 January 09, 2024 Dublin City Council Regular Meeting Agenda 6 Attachment 1 - Resolution Amending the Downtown Dublin Specific Plan to Eliminate Parking Requirements in the Retail District, Transit-Oriented District, and Village Parkway District
Attachment 2 - DDSP Amendments - Redlined Pages
Attachment 3 - Planning Commission Resolution No. 23-10 Item 6.2 - PowerPoint Presentation

7. UNFINISHED BUSINESS

7.1 Climate Action Plan 2030 and Beyond Implementation Status Report The City Council will receive a report on the implementation status of Climate Action Plan 2030 and Beyond and associated greenhouse gas emissions reductions achieved through calendar year 2022.

STAFF RECOMMENDATION:

Receive the report.

Staff Report
Attachment 1 - Climate Action Plan 2030 and Beyond Table 8-2 GHG Emissions Reduction Measures Monitoring and Reporting Program
Item 7.1 - PowerPoint Presentation

8. NEW BUSINESS

8.1 2022-2027 Capital Improvement Program – Project Status Report The City Council will receive a report on the status of current Capital Improvement Program projects.

STAFF RECOMMENDATION:

Receive the report.

Staff Report
Attachment 1 - Five-Year Capital Improvement Program 2022-2027 Update Item 8.1 PowerPoint Presentation

8.2 Disaster Preparedness Activities Update
The City Council will receive a report on the City’s current and planned emergency management and disaster preparedness activities including preparation of the Tri-Valley Hazard Mitigation Plan.

STAFF RECOMMENDATION:

Receive the report.

Staff Report
Item 8.2 - PowerPoint Presentation

9. CITY MANAGER AND CITY COUNCIL REPORTS
Brief information only reports from City Council and/or Staff, including committee reports and reports by City Council related to meetings attended at City expense (AB1234).

10. ADJOURNMENT
This AGENDA is posted in accordance with Government Code Section 54954.2(a) If requested, pursuant to Government Code Section 54953.2, this agenda shall be made available in appropriate alternative formats to persons with a disability, as required by 6 January 09, 2024 Dublin City Council Regular Meeting Agenda 7 Section 202 of the Americans with Disabilities Act of 1990 (42 U.S.C. Section 12132) (ADA), and the federal rules and regulations adopted in implementation thereof. To make a request for disability-related modification or accommodation, please contact the City Clerk’s Office (925) 833-6650 at least 72 hours in advance of the meeting. Upon receiving a request, the City will swiftly resolve requests for reasonable accommodation for individuals with disabilities, consistent with the federal ADA, and resolve any doubt in favor of accessibility.

Agenda materials that become available within 72 hours in advance of the meeting, and after publishing of the agenda, will be available at Civic Center, 100 Civic Plaza, and will be posted on the City’s website at www.dublin.ca.gov/ccmeetings.

Mission
The City of Dublin promotes and supports a high quality of life, ensures a safe and secure environment, fosters new opportunities, provides equity across all programs, and champions a culture of diversity and inclusion.
7 STAFF REPORT

CITY COUNCIL

Agenda Item 3.1
DATE: January 9, 2024
TO: Honorable Mayor and City Councilmembers
FROM: Linda Smith, City Manager
SUBJECT: Recognition of Centenarian Zainul Abedin Syed
Prepared by: Marsha Moore, MMC, City Clerk
EXECUTIVE SUMMARY:

The City Council will present a certificate to Centenarian Zainul Abedin Syed recognizing the milestone of reaching 100 years of life. Mr. Syed was born on November 23, 1923 and turned 100 on November 23, 2023. The City Council asked Staff to invite Mr. Syed to be recognized under Item 9 on December 5, 2023.

STAFF RECOMMENDATION:

Present the certificate.

FINANCIAL IMPACT:

None.

DESCRIPTION:

Under Item 9 on December 5, 2023, the City Council asked Staff to invite Zainul Abedin Syed, a local centenarian, to be recognized at an upcoming meeting. Mr. Syed was born on November 23, 1923, celebrating 100 years of life on November 23, 2023. The City Council will present a certificate to Mr. Syed honoring him and celebrating him on a life well lived.

STRATEGIC PLAN INITIATIVE:

None.

NOTICING REQUIREMENTS/PUBLIC OUTREACH:

The City Council Agenda was posted.
8

ATTACHMENTS:
1) Certificate of Recognition
9 Attachment 1

CERTIFICATE OF RECOGNITION
Given to

ZAINUL ABEDIN SYED
Born on November 23, 1923
The City of Dublin and its community honors and celebrates you on a life well lived! CONGRATULATIONS CENTENARIAN!
Presented by the
City Council of the City of Dublin
Dated: January 9, 2024
Mayor Melissa Hernandez Vice Mayor Sherry Hu
_______ Councilmember Jean Josey Councilmember Michael McCorriston Councilmember Kashef Qaadri 10 STAFF REPORT

CITY COUNCIL

Agenda Item 3.2
DATE: January 9, 2024
TO: Honorable Mayor and City Councilmembers
FROM: Linda Smith, City Manager
SUBJECT: 2023 Sponsor Recognition
Prepared by: Ivan San Pedro, Recreation Supervisor
EXECUTIVE SUMMARY:

The City Council will recognize sponsors who contributed to City events, programs, and facilities in 2023.

STAFF RECOMMENDATION:

Recognize the 2023 sponsors.

FINANCIAL IMPACT:

The City received over $73,910 in cash sponsorships and $1,650 in in-kind sponsorships in 2023.

Sponsorships help offset the cost of producing special events and operating City programs and facilities, reducing the overall impact on the General Fund.

DESCRIPTION:

Through its Donation and Sponsorship Policy, the City invites and encourages local businesses and corporations to partner as sponsors of the City, providing cash or in-kind contributions to support City events, programs, and facilities in exchange for appropriate sponsorship recognition.

Sponsors who contributed in 2023 are listed in Attachment 1.

The City Council does not need to take any action beyond recognizing the sponsors. According to the Donation and Sponsorship Policy adopted by the City Council in 2017, the City Council is only required to formally accept individual donations that exceed $45,000.

STRATEGIC PLAN INITIATIVE:

None.
11

NOTICING REQUIREMENTS/PUBLIC OUTREACH:

The City Council Agenda was posted.

ATTACHMENTS:
1) 2023 City of Dublin Sponsor List
12 EVENT OR DEPARTMENT CASH IN-KIND ITEM
St. Patrick's Day Celebration
Provident Credit Union $500
Hope Hospice $500
Patelco Credit Union $1,000
Aetna $1,200
Half Price Books $2,000
Joya Yoga $2,000
Comcast Cable $2,000
Go Green Driving School $2,000
Solar Bill Review $2,000
Sutter Health $2,000
East Bay Community Energy $2,000
Madden Marketing $2,000
Diageo $3,000
Safeway $4,000
Atlantis Orthadontics $4,000
Alamo Ace Hardware $6,000
5421 at Dublin Station-UDR Apartments $1,000
Empower Martial Arts $2,750
Stratford School $2,000
Foothill Chiropractic $2,000
Dublin United Soccer League $540
LAVTA $520
Shamrock 5K Fun Run and Walk
Azo Fitness Inc. $750
IBEW Local 595 $750
KeyPoint Credit Union $2,000
Boyce Mangin For Stanford Children's Health $750
Splatter
Half Price Books $800
Provident Credit Union $1,500
Joya Yoga $1,500
Patelco Credit Union $2,000
Waterford Dental Group $1,500
Stratford $500
Tree Lighting
Go Green Driving School $350
Amario Homes: Tri-Valley Real Estate $500
Harvest Fair
Rumble Boxing $150
Atlantis Orthodontics $300
2023 Donations & Sponsorships
Attachment 1
13 Empower Martial Arts $500
Challenge Dairy $150 Sample Butter Packets
Farmers Market
State Farm Insurance $300
Rumble Boxing $300
Baylight Baptist Church $300
Grace Family SF $300
Ian Chin Photography $300
KeyPoint Credit Union $1,400
Ace Hardware $3,000
Empower Martial Arts $1,000
Foothill Chiropractic $2,000
Events Team WGN $1,600
Anchor CM $1,400
Breakfast with Santa
5421 at Dublin Station-UDR Apartments $350
Events Team WGN $350
Backyard Block Party
Half Price Books $200
Trail Challenge
Azo Fitness Inc. $250
KeyPoint Credit Union $250
Empower Martial Arts $250
Sports Basement $250
IBEW Local 595 $500
Senior Center
The Vineyards $500
The Vineyards - Holiday DancEscape $1,200 150 small charcuterie boxes Ivy Park Residential Community - DancEscape $300 2 gift boxes for giveaway Access Community Health - Information Fair $250
TOTAL $73,910 $1,650
14 2023 Sponsor Recognition
City Council Meeting – Item 3.2
January 9, 2024
15 2023 Sponsorship Overview
• $73,910 received in cash sponsorships.
• $1,650 received in in-kind sponsorships.
• Funds and donated goods are used to offset the costs
of producing special events and running programs,
facilities and services.
16 St. Patrick’s Day Celebration
17 Spring Eggstravaganza
18 Farmers Market & Summer Concert Series
19 Picnic Flix
20 Splatter
21 Harvest Fair & Ghosts of Dublin
22 40th Annual Holiday Tree Lighting &
Breakfast with Santa
23 Senior Center: Info Fair & Holiday Craft Boutique
24 25
Thank You!
26 STAFF REPORT

CITY COUNCIL

Agenda Item 3.3
DATE: January 9, 2024
TO: Honorable Mayor and City Councilmembers
FROM: Linda Smith, City Manager
SUBJECT: Recognition of the 2023 “Deck the Homes” Holiday Home Decorating Contest Winners
Prepared by: Jennifer Li Marzi, Recreation Technician
EXECUTIVE SUMMARY:

The City Council will receive a presentation on the 2023 “Deck the Homes” Holiday Home Decorating Contest and present Certificates of Recognition to the winners.

STAFF RECOMMENDATION:

Present Certificate of Recognition to the 2023 “Deck the Homes” Holiday Home Decorating Contest winners.

FINANCIAL IMPACT:

Expenses for the program are included in the annual operating budget.

DESCRIPTION:

Background
The “Deck the Homes” Holiday Home Decorating Contest is intended to encourage and celebrate those residents who decorate their homes for the holidays. Organized by the Parks and Community Services Department, the program utilizes the Parks and Community Services Commissioners to serve as the judges. The program was introduced in 2018, making 2023 its sixth season.

Individual homes are judged in six categories. Winners receive a yard sign, a $50 gift card to a local business, and a Certificate of Recognition from the City Council. 2023 “Deck the Homes” Program
To promote the Holiday Home Decorating Contest, Staff utilized the City’s website and social media platforms, in addition to sending invitations to past participants. The deadline for submissions was December 8, 2023.
27

A total of 26 contest applications were received. Commissioners from the Parks and Community Services Commission individually judged participating homes by visiting locations December 11- 15, 2023.

At its meeting on December 18, 2023, the Parks and Community Services Commission voted on category winners. Contest winners were notified via email on December 19, 2023. They received yard signs to display their winning category and a gift card from a local business. The homes were judged based on the following categories and criteria:
 Seen from Space Award - Best use of lights and color.  Winter Wonderland Award - Best use of music, movement, and technology.  Spotlight Award – Judge’s choice.
 Over Inflated - Best use of inflatables.
 Deck the Halls Award - Best condo/apartment.
 Dashing Debut Award – First year contest entries.

Photos of the 2023 contest winners are included with this Staff Report (Attachment 1).

Deck the Homes Winners
Award Categories Winning Home Address
Seen from Space 7574 Sutton Place
Winter Wonderland 7287 Bedford Way
Spotlight 11913 Bloomington Way
Over Inflated 6815 Ione Way
Deck the Halls 5653 Iron Horse Parkway
Dashing Debut 8645 Ardmore Place
STRATEGIC PLAN INITIATIVE:

None.

NOTICING REQUIREMENTS/PUBLIC OUTREACH:

The City Council Agenda was posted.

ATTACHMENTS:
1) 2023 Holiday Home Decorating Contest Winners
2) 2023 Holiday Home Decorating Contest Flyer
28 2023 “Deck the Homes” Holiday
Home Decorating Contest
Contest Winners
Attachment 1
29 Seen From Space Award
Bonato Family – 7574 Sutton Ln.

Best Use of Lights and Color
Attachment 1
30 Winter Wonderland Award
Brandt Family – 7287 Bedford Way
Best Use of Music, Movement & Technology
Attachment 1
31 Spotlight Award
Gasper Family - 11913 Bloomington Way
Judge’s Choice
Attachment 1
32 Over Inflated Award
McCormack Family – 6815 Ione Way
Best Use of Inflatables
Attachment 1
33 Deck the Halls Award
Flebut Family – 5653 Iron Horse Parkway
Best Condo/Apartment
Attachment 1
34 Dashing Debut Award
Grymonprez Family – 8645 Ardmore Place
First Year Contest Entry
Attachment 1
35 CITY OF DUBLIN
2023 Holiday Home Decorating Contest
“decK THE HOMES”

IN OUR NEW AMERICAN BACKYARD
Do you have the most festive holiday display in town?
The City of Dublin invites Dublin residents to participate in the City’s Holiday Home Decorating Contest. One winner will be chosen from each of the following categories:
• Seen from Space Award – best use of lights and color
• Winter Wonderland Award – best use of music, movement, and technology • Over-Inated Award – best use of inatables
• Deck the Halls Award – best decorated apartment/condo/balcony • Dashing Debut Award –
rst year contest entry
• Spotlight Award – judges choice
Category winners will receive a special yard sign and a $50 gift certicate from a local business.

Entry forms are available online at www.dublin.ca.gov/holidayhappenings or by request from [email protected].

The deadline to enter is Friday, December 8 at 4:00 p.m. Judging will take place December 11-15, and winners will be announced on December 19.

Attachment 2
36 2023 “Deck the Homes” Holiday
Home Decorating Contest
City Council Meeting – Item 3.3
January 9, 2024
37 Deck the Homes
• 6thYear for Residential Home Decorating Contest.
• Judges - Commissioners from the Parks & Community Services Commission.
• Winners selected at the December 18, 2023, Parks & Community Services Commission meeting.
• Award winners received yard signs, Certificates of Recognition and a gift card to a local business.
38 Deck the Homes
• 26 individual homes
• 6 categories:
o Seen From Space - Best use of Lights and Color
o Winter Wonderland Award - Best use of Music, Movement, & Technology o Over-Inflated Award - Best use of Inflatables
o Deck the Halls Award - Best Decorated Apartment/Condo/Balcony/Door o Dashing Debut Award - First Year Contest Participant (NEW) o Spotlight Award - Judges’ Choice (NEW)
39 Deck the Homes Map
40 Contest Winners
41 Seen From Space Award
Bonato Family – 7574 Sutton Lane
Best Use of Lights and Color 42
Winter Wonderland Award
Brandt Family – 7287 Bedford Way
Best Use of Music, Movement & Technology 43
Spotlight Award (New)
Gasper-Pena Family - 11913 Bloomington Way
Judge’s Choice 44
Over Inflated Award
McCormack Family – 6815 Ione Way
Best Use of Inflatables 45
Deck the Halls Award
Flebut Family – 5653 Iron Horse Parkway
Best Condo/Apartment 46
Dashing Debut Award (New)
Grymonprez Family – 8645 Ardmore Place
First Year Contest Entry 47
Thank You!
2023 Winners 48

STAFF REPORT

CITY COUNCIL

Agenda Item 5.1
EXECUTIVE SUMMARY:

The City Council will consider approval of the minutes of the December 19, 2023 Regular City Council Meeting.

STAFF RECOMMENDATION:

Approve the minutes of the December 19, 2023 Regular City Council Meeting.

FINANCIAL IMPACT:

None.

DESCRIPTION:

The City Council will consider approval of the minutes of the December 19, 2023 Regular City Council Meeting.

STRATEGIC PLAN INITIATIVE:

None.

NOTICING REQUIREMENTS/PUBLIC OUTREACH:

The City Council Agenda was posted.

ATTACHMENTS:
1) December 19, 2023 Regular City Council Meeting Minutes DATE: January 9, 2024
TO: Honorable Mayor and City Councilmembers
FROM: Linda Smith, City Manager
SUBJECT: Approval of December 19, 2023 Regular City Council Meeting Minutes Prepared by: Marsha Moore, MMC, City Clerk
49 MINUTES OF THE CITY COUNCIL

OF THE CITY OF DUBLIN
Regular Meeting: December 19, 2023

DUBLIN CITY COUNCIL MINUTES

REGULAR MEETING
DECEMBER 19, 2023
The following are minutes of the actions taken by the City of Dublin City Council. A full video recording of the meeting with the agenda items indexed and time stamped is available on the City’s website at: https://dublin.ca.gov/ccmeetings Pursuant to AB 2449, Councilmember Kashef Qaadri attended the Regular Meeting remotely for “just cause” due to a contagious illness that prevented him from attending in person. All votes during the remote session were conducted by roll call vote.

REGULAR MEETING 7:00 PM
A Regular Meeting of the Dublin City Council was held on Tuesday, December 19, 2023, in the City Council Chamber. The meeting was called to order at 7:00 PM by Mayor Hernandez. 1) CALL TO ORDER
Attendee Name Status
Melissa Hernandez, Mayor Present
Michael McCorriston, Vice Mayor Present
Jean Josey, Councilmember Present
Dr. Sherry Hu, Councilmember Present
Kashef Qaadri, Councilmember Present (via Zoom)
2) PLEDGE OF ALLEGIANCE
Councilmember Qaadri announced he was participating remotely for ‘just cause’ due to a contagious illness and had no one in the room with him. 3) PRESENTATIONS AND PROCLAMATIONS – None.
4) PUBLIC COMMENT
Ed Romano provided public comment.

Asaad Traina provided public comment.

Asma Shaikh provided public comment.

Naveed D. provided public comment.

Attachment 1
50 DUBLIN CITY COUNCIL MINUTES

REGULAR MEETING
DECEMBER 19, 2023
Bya Founas provided public comment.

Musa Tariq provided public comment.

Grant Esomonu provided public comment.

Sadaf provided public comment.

Brent Songey provided public comment.

Mike Grant provided public comment.

Salma M. provided public comment.

Omar Maher provided public comment.

Naomi Smoller provided public comment.

Lubna Hasan provided public comment.

Rizwan Sharif provided public comment.

Farah Rahhal provided public comment.

Carolyn provided public comment.

Faran Sikandar provided public comment.

Majid Mahmood provided public comment.

NS provided public comment.

Aysha Abraibesh provided public comment.

Mahz S. provided public comment.

Michael Cede provided public comment.

DD provided public comment.

Moina Masud provided public comment.

Haneen provided public comment.

Hala A. provided public comment.
51 DUBLIN CITY COUNCIL MINUTES

REGULAR MEETING
DECEMBER 19, 2023
Stan Woods provided public comment.

Suzanne Abouremeleh provided public comment.

Nishat Ahmed provided public comment.

Subramanian Tiruchirapalli provided public comment.

Jasmine Riad provided public comment.

Hamzeh provided public comment.

Yasmin Sallak provided public comment.

Seema Badar provided public comment.

Spojmie Nasiri provided public comment.

Satchel Forrester provided public comment.
5) CONSENT CALENDAR

5.1) Approved the December 5, 2023 Regular City Council Meeting Minutes.

5.2) Adopt the Resolution No. 125-23 titled, “Making an Appointment to the Alameda County Mosquito Abatement District Board of Trustees.”

5.3) Adopted Resolution No. 126-23 titled, “Approving an Agreement with Matrix Consulting Group, Ltd. to Conduct a Full Cost Allocation Plan and User Fee Study.”

5.4) Received a notification of the City Engineer’s pending approval of the Final Map for Tract 8563, Francis Ranch, adopted Resolution No. 127-23 titled, “Approving the Agreement for Long Term Encroachment for Landscape Features for Tract 8563, Francis Ranch,” and adopted Resolution No. 128-23 titled, “Ordering the Annexation of Francis Ranch (Tract 8563) Into the Dublin Ranch Street Lighting District 1999-1.”

5.6) Approved the 2024 City Council Meeting Calendar.

5.7) Received a report of payments issued from October 1, 2023 – October 31, 2023, totaling $10,986,684.19 and November 1, 2023 – November 30, 2023, totaling $9,871,933.44.

5.8) Waived the second reading and adopted Ordinance No. 07-23 titled, “Approving Amendments to the Effective Date of Ordinances 16 -22 and 17-22 Amending the Planned Development Zoning for the Dublin Transit Center Sites D-2 and E-2 and for Hacienda Crossings Shopping Center.”
52 DUBLIN CITY COUNCIL MINUTES

REGULAR MEETING
DECEMBER 19, 2023

5.9) Waived the second reading and adopted Ordinance No. 08-23 titled, “Levying Special Taxes Within City of Dublin Community Facilities District No. 2023-1 (East Ranch).”

5.10) Adopted Resolution No. 130-23 titled, “Accepting the Dublin Boulevard Pavement Rehabilitation Project, CIP No. ST0117 and ST0120, Federal Aid No. STPL-5432 (021).”

5.11) Adopted Resolution No. 131-23 titled, “Amending and Restating the Rules for the Conduct of Meetings of the City Council.”

5.12) Annual Comprehensive Financial Report (ACFR) and Annual Audit for Fiscal Year Ending June 30, 2023 and Supplemental Reports Completed by the City’s Independent Auditors.

5.13) Adopted Resolution No. 132-23 titled, “Authorizing Submittal of Individual Applications for CalRecycle Grant Programs.”
On a motion by Councilmember Josey, seconded by Vice Mayor McCorriston, and by unanimous vote, the City Council adopted the Consent Calendar, except for item 5.5.

RESULT: ADOPTED [UNANIMOUS]
MOVED BY: Jean Josey, Councilmember
SECOND: Michael McCorriston, Vice Mayor
AYES: Hernandez, McCorriston, Josey, Hu, Qaadri

5.5) Youth Mini-Grant Funding Recommendations Approval
This item was pulled from the consent calendar by Councilmember Qaadri for a clarifying question.

On a motion by Councilmember Qaadri and seconded by Councilmember Josey, and by unanimous vote, the City Council adopted Resolution No. 129-23 titled, “Approving Funding Recommendations for the Fiscal Year 2023-24 Youth Advisory Committee Mini-Grant Program.”
RESULT: ADOPTED [UNANIMOUS]
MOVED BY: Kashef Qaadri, Councilmember
SECOND: Jean Josey, Councilmember
AYES: Hernandez, McCorriston, Josey, Hu, Qaadri
53 DUBLIN CITY COUNCIL MINUTES

REGULAR MEETING
DECEMBER 19, 2023
6) PUBLIC HEARING

6.1) Vacation of Right-of-Way on Croak Road and Approving Quitclaim Deed The City Council received a presentation regarding a vacation of public street right-of-way on Croak Road between South Terracina Drive and Central Parkway for the Francis Ranch development (formerly East Ranch).

Mayor Hernandez opened the Public Hearing.

Upon receiving no public comment, Mayor Hernandez closed the Public Hearing.

On a motion by Vice Mayor McCorriston, seconded by Councilmember Hu, and by unanimous vote, the City Council adopted Resolution No. 133-23 titled “Vacating Right-ofWay on Croak Road and Approving a Quitclaim Deed.” RESULT: ADOPTED [UNANIMOUS]
MOVED BY: Michael McCorriston, Vice Mayor
SECOND: Dr. Sherry Hu, Councilmember
AYES: Hernandez, McCorriston, Josey, Hu, Qaadri

6.2) Downtown Dublin Preferred Vision Implementation General Plan and Downtown Dublin Specific Plan Amendments
The City Council received a presentation regarding proposed amendments to the General Plan and the Downtown Dublin Specific Plan to further implement the Downtown Dublin Preferred Vision approved by the City Council in 2019.

Mayor Hernandez opened the Public Hearing.

Tom Evans provided public comment.

Norm Lewandowski provided public comment.

Greg Bonato provided public comment.

Mayor Hernandez closed the Public Hearing.

On a motion by Councilmember Qaadri, seconded by Mayor Hernandez, and by a 4-to-1 vote, the City Council adopted Resolution No. 134-23 titled, “Amending the General Plan and Downtown Dublin Specific Plan to Further Implement the Downtown Dublin Preferred Vision,” as amended to include edit of Building Stepbacks, item 4 of the table on page 57, Section 4.1 Retail District Development Standards, to read, ‘Encouraged on upper floors, but not required. Building elevations facing the park are required to stepback upper floors.’ 54 DUBLIN CITY COUNCIL MINUTES

REGULAR MEETING
DECEMBER 19, 2023
RESULT: ADOPTED [4-to-1]
MOVED BY: Kashef Qaadri, Councilmember
SECOND: Melissa Hernandez, Mayor
AYES: Hernandez, McCorriston, Josey, Qaadri
NOES: Hu
Mayor Hernandez called for a break at 9:55 PM.

Mayor Hernandez reconvened the meeting at 10:00 PM.
7) UNFINISHED BUSINESS – None.
8) NEW BUSINESS

8.1) Selection of Vice Mayor
The City Council’s policy is to select, in December of each year, a member of the City Council to serve as Vice Mayor for a period of one year. In the absence of the Mayor, the Vice Mayor would become Mayor Pro Tempore and would assume the temporary responsibilities of the Mayor.

The City Council received Mayor Hernandez’s suggestion of Councilmember Hu as Vice Mayor for a one-year period.

On a motion by Mayor Hernandez, seconded by Vice Mayor McCorriston, and by unanimous vote, Councilmember Hu was appointed to serve as Vice Mayor for a one-year period from December 2023 – December 2024.

RESULT: APPOINTED [UNANIMOUS]
MOVED BY: Melissa Hernandez, Mayor
SECOND: Michael McCorriston, Vice Mayor
AYES: Hernandez, McCorriston, Josey, Hu, Qaadri
55 DUBLIN CITY COUNCIL MINUTES

REGULAR MEETING
DECEMBER 19, 2023
9) CITY MANAGER AND CITY COUNCIL REPORTS
The City Council and Staff provided brief information-only reports, including committee reports and reports by City Council related to meetings attended at City expense (AB1234).

By consensus, the City Council requested that Staff report back on trees lost to the storms in 2022 and the replacement of those trees.

By consensus, the City Council requested that Staff prepare a certificate of recognition for the Under Sheriff, Rich Lucia and requested Staff to add signatures of the entire City Council to certificates of recognition when requested for volunteers in the community.

Mayor Hernandez asked for a moment of silence in memory of Christopher Kinzel, a member of the Dublin Rotary and Vice President at TJKM, who passed away on December 19, 2023.
10) ADJOURNMENT
Mayor Hernandez adjourned the meeting at 10:29 PM.

Mayor
ATTEST:

City Clerk
56 STAFF REPORT

CITY COUNCIL

Agenda Item 5.2
DATE: January 9, 2024
TO: Honorable Mayor and City Councilmembers
FROM: Linda Smith, City Manager
SUBJECT: Annual Proclamation
Prepared by: Marissa Clevenger, Administrative Technician EXECUTIVE SUMMARY:

The City Council will review the Official List of Proclamations and consider approval of the Annual Proclamation.

STAFF RECOMMENDATION:

Accept the Official List of Proclamations and approve the Annual Proclamation.

FINANCIAL IMPACT:

None.

DESCRIPTION:

The City maintains an Official List of Proclamations that contains proclamations that have previously been presented or requested by the City Council on an annual basis, as well as proclamations recognized nationally through the Federal Register.

According to the process approved by the City Council in September 2022, Staff brings the Official List back to the City Council for review and approval each January, and approves a single, comprehensive proclamation recognizing each of the individual proclamations from the Official List. Staff then publishes the Official List on the City website and recognizes the proclamations through social media throughout the year. Community members who wish to receive a proclamation in person at a City Council meeting can request via the City’s website to have it prepared and presented.

Attached is the Official List for 2024, updated with new proclamations approved by the City Council in 2023 (World Polio Day; Pancreatic Cancer Awareness Month) and some that were 57

presented in 2022 and inadvertently left off the list adopted in September 2022 (Library Week; Arts, Culture, and Creativity Month; and Small Business Saturday). There were no new month proclamations in the Federal Register in 2023, however some were named slightly different, and Staff has updated the list and proclamation to reflect those changes. Staff asks that the City Council accept this as the City of Dublin Official List of Proclamations for 2024 and approve the Annual Proclamation.

STRATEGIC PLAN INITIATIVE:

None.

NOTICING REQUIREMENTS/PUBLIC OUTREACH:

The City Council Agenda was posted.

ATTACHMENTS:
1) Official List of Proclamations
2) City of Dublin Annual Proclamation
58 Attachment 1
City of Dublin
Official List of Proclamations (2024)

JANUARY
Mentoring Month
Stalking Awareness Month
Slavery and Human Trafficking Prevention Month

FEBRUARY
Teen Dating Violence Awareness and Prevention Month
African American History Month/ Black History Month
American Heart Month
Career and Technical Education Month
Lunar New Year
MARCH
Women's History Month
Irish-American Heritage Month
Colorectal Cancer Awareness Month
American Red Cross Month
Meals on Wheels
Disabilities Awareness Month
APRIL
Arbor Day
Sexual Assault Awareness and Prevention Month
Donate Life Month
Cancer Control Month
Financial Capability Month
Child Abuse Prevention Month
Second Chance Month
Fair Housing Month
Crime Victims' Rights Week
Month of the Military Child
Arab American Heritage Month
Library Week
Arts, Culture, and Creativity Month
MAY
Bike Month and Bike to Work Day
Small Business Week
Public Works Week
Affordable Housing Week
Lupus Awareness Month
Mental Health Awareness Month
Physical Fitness and Sports Month
Building Safety Month
Foster Care Month
59 Older Americans Month
Jewish American Heritage Month
Asian American and Pacific Islander Heritage Month
Correctional Workers Week
Job's Daughters International Day
Municipal Clerk's Week
JUNE
LGBTQ+ Pride Month and Flag Raising
Flag Day and National Flag Week
National Ocean Month
Caribbean American Heritage Month
Homeownership Month
Great Outdoors Month
African American Music Appreciation Month
Juneteenth
Gun Violence Awareness Day and Month
World Elder Abuse Day and Month
Immigrant Heritage Month
JULY
Pledge to America's Workers Month
AUGUST
National Night Out
American Muslim Appreciation and Awareness Month

SEPTEMBER
Suicide Prevention Awareness Month
Hispanic Heritage Month
Childhood Cancer Awareness Month
Wilderness Month
Prostate Cancer Awareness Month
Preparedness Month
Ovarian Cancer Awareness Month
Childhood Obesity Awareness Month
Recovery Month
Constitution Week
Sickle Cell Awareness Month
Mid-Autumn / Moon Festival

OCTOBER
Walk and Roll to School
Fire Prevention Week
Red Ribbon Week
Bullying Prevention Month & Unity Day
Breast Cancer Awareness Month
Domestic Violence Awareness Month
Youth Justice Action Month
Disability Employment Awareness Month
60 Cybersecurity Awareness Month
Arts and Humanities Month
Global Diversity Awareness Month
Manufacturing Day
Children's Environmental Health Month
Diwali
Hindu American Awareness and Appreciation Month
Clean Energy Action Month
Substance Abuse Awareness Month
Italian American Heritage Month
German American Heritage Month
World Polio Day

NOVEMBER
Native American Heritage Month
Family Caregivers Month
Diabetes Month
Entrepreneurship Month
Critical Infrastructure Security and Resilience Month
College Application Month
Alzheimer's Disease Awareness Month
Adoption Month
Veterans and Military Families Month
United Against Hate
American History and Founders Month
Lung Cancer Awareness Month
Pancreatic Cancer Awareness Month
Small Business Saturday

DECEMBER
Impaired Driving Prevention Month
61 Attachment 2

A PROCLAMATION OF THE

CITY OF DUBLIN, CALIFORNIA
“Annual Proclamation 2024”
WHEREAS, the City of Dublin wishes to recognize organizations within the City by publicly and formally declaring notable occasions by the issuance of proclamations; and
WHEREAS, at its January 9, 2024 meeting, the City Council adopted an updated Official List of Proclamations for the City of Dublin; and
WHEREAS, the City of Dublin invites organizations to ceremonially receive proclamations throughout the year; and WHEREAS, the City of Dublin promotes and supports a high quality of life, ensures a safe and secure environment, fosters new opportunities, provides equity across all programs, and champions a culture of diversity and inclusion.

NOW, THEREFORE, BE IT RESOLVED in support of the City of Dublin mission, the Dublin City Council does hereby proclaim the following in 2024 throughout the City of Dublin:

January
Mentoring Month
Stalking Awareness Month
Slavery and Human Trafficking Prevention
Month
April
Arbor Day
Sexual Assault Awareness and Prevention
Month
Donate Life Month
Cancer Month
Financial Capability Month
Child Abuse Prevention Month
Second Chance Month
Fair Housing Month
Crime Victims' Rights Month
Month of the Military Child
Arab American Heritage Month
Library Week
Arts, Culture, and Creativity Month
February
Teen Dating Violence Awareness and
Prevention Month
African American History Month/ Black
History Month
American Heart Month
Career and Technical Education Month
Lunar New Year
May
Small Business Week
Public Works Week
Affordable Housing Week
Lupus Awareness Month
Mental Health Awareness Month
Physical Fitness and Sports Month
Building Safety Month
Foster Care Month
Older Americans Month
Jewish American Heritage Month
Asian American and Pacific Islander
Heritage Month
Correctional Workers Week
Job's Daughters International Day
Municipal Clerk's Week
Bike Month and Bike to Work Day
March
Women's History Month
Irish-American Heritage Month
Colorectal Cancer Awareness Month
American Red Cross Month
Meals on Wheels
Disabilities Awareness Month
June
LGBTQ+ Pride Month and Flag Raising
Flag Day and National Flag Week
National Oceans Month
Caribbean-American Heritage Month
Homeownership Month
Great Outdoors Month
African American Music Appreciation
Month
Juneteenth
Gun Violence Awareness Day and Month
World Elder Abuse Day and Month
Immigrant Heritage Month
62 Attachment 2
July
Pledge to America's Workers Month
October
Walk and Roll to School
Fire Prevention Week
Red Ribbon Week
Bullying Prevention Month & Unity Day
Breast Cancer Awareness Month
Domestic Violence Awareness Month
Youth Justice Action Month
Disability Employment Awareness
Month
Cybersecurity Awareness Month
Arts and Humanities Month
Global Diversity Awareness Month
Manufacturing Day
Children's Environmental Health Month
Diwali
Hindu American Awareness and
Appreciation Month
Clean Energy Action Month
Substance Abuse Awareness Month
Italian American Heritage Month
German American Heritage Month
World Polio Day
August
National Night Out
American Muslim Appreciation and
Awareness Month
November
Native American Heritage Month
Family Caregivers Month
Diabetes Month
Entrepreneurship Month
Critical Infrastructure Security and
Resilience Month
College Application Month
Alzheimer's Disease Awareness Month
Adoption Month
Veterans and Military Families Month
United Against Hate
American History and Founders Month
Lung Cancer Awareness Month
Pancreatic Cancer Awareness Month
Small Business Saturday
September
Suicide Prevention Awareness Month
Hispanic Heritage Month
Childhood Cancer Awareness Month
Wilderness Month
Prostate Cancer Awareness Month
Preparedness Month
Ovarian Cancer Awareness Month
Childhood Obesity Awareness Month
Recovery Month
Constitution Week
Sickle Cell Awareness Month
Mid-Autumn Festival / Moon Festival
December
Impaired Driving Prevention Month
Mayor Melissa Hernandez Vice Mayor Sherry Hu
_______ Councilmember Jean Josey Councilmember Michael McCorriston Councilmember Kashef Qaadri 63 STAFF REPORT

CITY COUNCIL

Agenda Item 5.3
DATE: January 9, 2024
TO: Honorable Mayor and City Councilmembers
FROM: Linda Smith, City Manager
SUBJECT: Mayor’s Appointments to Heritage and Cultural Arts Commission Unscheduled Vacancy and Parks and Community Services Commission Alternate Unscheduled Vacancy
Prepared by: Marsha Moore, MMC, City Clerk
EXECUTIVE SUMMARY:

The City Council will consider the Mayor’s appointments to fill an unscheduled vacancy on the Heritage and Cultural Arts Commission and an alternate unscheduled vacancy on the Parks and Community Services Commission.

STAFF RECOMMENDATION:

Confirm the Mayor’s appointments of Darren Phillips to the Heritage and Cultural Arts Commission for the remainder of a term ending December 2026 and Eric Nielsen as an alternate on the Parks and Community Services Commission for the remainder of a term ending December 2024.

FINANCIAL IMPACT:

None.

DESCRIPTION:

In September 2023, an unscheduled vacancy occurred on the Heritage and Cultural Arts Commission. In addition, the Parks and Community Services Commission and Senior Center Advisory Committee had unscheduled vacancies for alternate positions. A notice seeking applications was posted on October 13, 2023 with a deadline of November 3, 2023.

Heritage and Cultural Arts Commission
Mayor Hernandez reviewed applications from alternate Darren Phillips, in addition to applications from Keith Kang, Gerard Molnar, and Jasmin Schroder.
64

Parks and Community Services Commission
Mayor Hernandez reviewed applications from Alam Akbar, Probaho Chakrabarty, Marissa Clavin, Eric Nielsen, and John Wu.

Senior Center Advisory Committee
The City received one application for this vacancy, therefore Staff will re-open the recruitment to build a larger pool of applicants.

STRATEGIC PLAN INITIATIVE:

None.

NOTICING REQUIREMENTS/PUBLIC OUTREACH:

The City Council Agenda was posted, and applicants were notified.

ATTACHMENTS:
1) Applications for the Heritage and Cultural Arts Commission 2) Applications for Parks and Community Services Commission 65 Attachment 1
66 67
68 Application Questions V
What education, training or experience do you have in cultural arts or heritage? I was a board member of the Pleasanton Cultural Art Council for about 10 years and Del Valle Fine Art for a couple of years in the past In my personal interest in art, I took art history classes from the Las Positas/ Chabot college.

Although my passion was in art and music from my childhood, I ended up with my career in computer field. Now that I am retired and settle down in Dublin, I'd like to pursue my passion contributing to the community I live.

List the artistic, cultural, and/or historic activities in which you have participated (particularly within the City of Dublin).

I frequently join and enjoy music in the park at Emerald park. The opera (La Boheme) in the park was my favorite. I took art classes offered from the senior center, which I enjoyed very much. My imitation painting of Cezanne was posted at the center. In my personal interest in art, I took art history classes from the Las Positas/ Chabot college.

Dublin has a rich heritage that has been preserved through parks, facilities, and programs. Dublin's recent history comprises diverse growth and demographics. How do you bridge the pioneer era with the more recent growth that has shaped what Dublin is today?
In my experience from Pleasanton Cultural Art Council, I realize there are so many children in diverse ethnic background pursuing art with excellent talents. I believe the city can play a significant role to encourage and promote those youngsters to grow their passion in art.

What knowledge do you have of public art and public art programs in Dublin? Other than being appreciative of the art works displayed in the parks as an average citizen, I don't have a specific knowledge in public art.

What is the most important contribution you feel you can make as a member of the Heritage & Cultural Arts Commission? My passion in art, and flexible time I have is my best asset to contribute to the community.

Please list any current or recent membership in arts, culture or heritage organizations.

I was a member of De Young Museum, Legend of Honor supporters in San Francisco, and am currently supporting San Francisco Conservatory of Music.

What experience do you have serving on advisory committees, task forces, boards or commissions? I was a board member of the Pleasanton Cultural Art Council for about 10 years and Del Valle Fine Art for a couple of years in the past In my personal interest in art, I took art history classes from the Las Positas/ Chabot college.

From my past professional experience in the high tech field I acquired an excellent skill in organizing and managing project with excellent communication.

Why are you interested in serving on the Heritage and Cultural Arts Commission? Although my passion was in art and music from my childhood, I ended up with my career in computer field. Now that I am retired and settled down in Dublin, I'd like to pursue my passion contributing to the community I live. 69 70
Application Questions
What education, training or experience do you have in cultural arts or heritage? I was in the video production business for over 20 years, five of them in the Bay Area, which is an artistic, creative field.

I'm a history buff and read historical novels about events cities, sports, music, movies, you name it.

List the artistic, cultural, and/or historic activities in which you have participated (particularly within the City of Dublin).

Walked in the St. Patrick's Day parade for many years when my daughters were students at St. Raymond's then at Murray and Wells. My one daughter danced at McBride Irish School of Dance and performed for years at the St. Patrick's Day festival.

Dublin has a rich heritage that has been preserved through parks, facilities, and programs. Dublin's recent history comprises diverse growth and demographics. How do you bridge the pioneer era with the more recent growth that has shaped what Dublin is today?
The diverse demographic that is here today will write their own history in Dublin and the Heritage and Cultural Arts Commission will be there to record it. But, also, the present day demographic needs to educate themselves on the history of where they live and celebrate its successes and learn from their mistakes. It will make for a richer more well rounded community.

What knowledge do you have of public art and public art programs in Dublin? Like most art I know what I like and I think I can speak for the average Joe when it comes to accessing what the community will appreciate and learn from.

What is the most important contribution you feel you can make as a member of the Heritage & Cultural Arts Commission? My passion for my adopted community. My wife was born and raised here. I grew up in Chicago. We were going to raise our family in the Midwest when unforeseen circumstances brought us back here. The first couple of years were rough, I admit. We had a beautiful home in Illinois but real estate was so expensive here that it was tough to find something. I think the early struggles then the settling in and watching our girls and ourselves grow into the community gives me a unique perspective that I can share with the commission.

Please list any current or recent membership in arts, culture or heritage organizations.

We were members of the California Academy of Science and the Monterey Bay Aquarium for years when my daughters were younger.

What experience do you have serving on advisory committees, task forces, boards or commissions? N/A
This will be my first.

Whv are vou interested in servina on the Heritaae and Cultural Arts Commission? I want to give back to my community with my time and expertise. Also, I love history and will be really interested in learning about Dublin’s past and future.
71 72
Application Questions
What education, training or experience do you have in cultural arts or heritage? My education and training is with Working local heritage events and attending events where our wonderful historian shares the history. They are not formaljust out of sheer curiosity and opportunity to learn.

List the artistic, cultural, and/or historic activities in which you have participated (particularly within the City of Dublin).

I have attended and toured carparks 80th anniversary and Dublin's 40th anniversary. Also attended the local soccer leagues 30 anniversary some years back. with all these events came the wonderful presentations and Q&A from Steven the local Historian. I also own the thumb drive with the neat video of the 40 years in Dublin. Also work the Fall Festivals, splatter, St. Patrick's festival.

Dublin has a rich heritage that has been preserved through parks, facilities, and programs. Dublin's recent history comprises diverse growth and demographics. How do you bridge the pioneer era with the more recent growth that has shaped what Dublin is today?
Heritage falls festival keeps local history alive with the location and activities such as turning butter. Splatter is a great showcase of different cultures in the performances and booths. With that said we can continue with expanding and adding a few celebrations such asJuneteenth and Holi (festival of colors) or on smaller scales offering more divers classes in the new Cultural Arts Center. Such as music classes that are of different cultural back grounds and significance.

What knowledge do you have of public art and public art programs in Dublin? Well the new building and arts center will have moving walls to help show case local artists and have a gallery. Along with the new box theater giving the city more designated space to develop and cultivate the arts and new developing culture here in Dublin. We have the electric boxes that are painted by local artists. Senior center show cases the art by the artist in their artist studio. We helped Camp parks with finding Muralists for their youth art wall.

What is the most important contribution you feel you can make as a member of the Heritage & Cultural Arts Commission? I will contribute to finding way to incorporate the old with the new and finding more ways to share history with our young community members.

Please list any current or recent membership in arts, culture or heritage organizations.

I don't have memberships, but I do enjoy going to art galleries and museums with my family I do the Livermore art walk.

What experience do you have serving on advisory committees, task forces, boards or commissions? I serve on DUSO LCAP since 2018 I recently have taken part in an Eastern Alameda Needs Assessment committee.

I am on the Dublin Rotary Board. I have severed in the past on many committees for various schools. I have done DUSO boundary committee, site council for Wells Middle School. PFC and site council for Dublin Elementary. I currently serve on a Diversity and Equity committee for the district.

Why are you interested in serving on the Heritage and Cultural Arts Commission? I would be a great addition I love this City I serve this city in many ways and am fascinated with its history and have a deep appreciation for it and how it has been preserved. With that I would like to help continue not only preserving the history but also preserving the new history that is in the making.
73 Attachment 2
74 and would like to give back if I can.

How do you feel about user fees for recreation programs and park/facility reservations? I'm good with fees for reservations. They should be built into league fees. However, I'd like to keep them low as possible so as not to prevent accessibility.

How do you feel about making a decision for the overall good of the community but unpopular with neighbors, residents, or organizations?
I believe that is what a committee has to do once in a while.

What is the most important contribution you can make as a member of the Parks and Community Services Commission? Coming from my history as a user of the services, I think I can provide a good representation of the community's views and would work to keep everything accessible and fun.

Why are you interested in serving on the Parks and Community Services Commission? Like I mentioned earlier, I like to give back to my City. My boys are grown and I have more time now to be involved.

In what organizations are you currently a member? Please list.

I'm taking the Inside Dublin course currently. I'm not part of any other organizations right now.

What knowledge do you have of the City-owned community facilities in Dublin, such as the Dublin Senior Center, Shannon Community Center, or The Wave? Have you or a family member rented facilities with the City of Dublin? I have been to all those places many times. We used to rent the community center for Little League events now and then. I haven't done a lot with the Senior Center or the Wave.

How can the City provide better equity and inclusion to all persons that use our parks, trails, and facilities, and access our programs? I'd imagine Social Media advertising is being used. I still like getting the booklet in the mail, but I'm older than a lot of the target audience. I would say to keep using snail mail for any Senior Center ads since many folks of that age still aren't friends with computers. 75 76
77 78
have also reserved spaces for birthday parties at various Dublin location, through Rec. My elder kid has also availed the after-school rec program at Amador Elementary. It has also become my habit to check the recreation guide as soon as it is published so that we can reserve our spots at the earliest.

How do you feel about user fees for recreation programs and park/facility reservations? Fees are very generous. We need to look into the accounting books and figure out the impact on the exchequer and accordingly take steps to rationalize the fees, compared to our neighborhood cities.

How do you feel about making a decision for the overall good of the community but unpopular with neighbors, residents, or organizations?
Dublin is the home of rational individuals. Even if we take an unpopular decision, if we socialize that evenly within the community, I am definitely we can get a consensus.

What is the most important contribution you can make as a member of the Parks and Community Services Commission? Coming from a Consultiing background (professionally), I can contribute in strategy, long term/short term planning, event planning and any other activities related to the smooth functioning of Dublin Park and recreation.

Why are you interested in serving on the Parks and Community Services Commission? Dublin is my adopted hometown and my family has long term interest in Dublin. Dublin Park and Recreation has an very important part to play in keeping the city vibrant and lively. Rather than sitting on the fence, I would like to participate and make my contribution in this goal.

In what organizations are you currently a member? Please list.

Past member of Positano Homeowner Association
What knowledge do you have of the City-owned community facilities in Dublin, such as the Dublin Senior Center, Shannon Community Center, or The Wave? Have you or a family member rented facilities with the City of Dublin? I do have extensive knowledge about Wave as my family members have regularly taken classes there. We have attended birthday parties in these facilities as well. I do not have much info on the Senior Center though.

How can the City provide better equity and inclusion to all persons that use our parks, trails, and facilities, and access our programs? I have a few idea, one of them being including Corporates organize their events in the trails and parks of Dublin. I am associated with Oracle and Kaiser Permanente ( Pleasanton) Heartwalk and if we can bring them in Dublin, we can have more participation. Dublin's diversity needs also be acknowledged, which could be done by recognizing some diverse events in our facilities 79 80
throughout the summers. I have worked with city staff in reserving city facilities for Dublin Little League, Briarhill Swim Team and Murray Elementary School.

How do you feel about user fees for recreation programs and park/facility reservations? They are necessary to continue to provide facilities that are up-to-date and cared for. I do believe that we need to be responsible in terms of what those fees are but they are necessary.

How do you feel about making a decision for the overall good of the community but unpopular with neighbors, residents, or organizations?
Again, similar to above sometimes it is necessary. It all comes down to communication and transparency and while people w ll continue to be upset with an unpopular opinion, if we can share how we got there and why, the hope would be that we can help ease some people's minds (you will never please everyone). I was on the school district boundary committee recently and there were several unpopular decisions that had to be made for the overall good of our community but as I have been able to have conversations with families and explain the complexities, there is usually an understanding that happens.

What is the most important contribution you can make as a member of the Parks and Community Services Commission? I will bring a deep dedication to the process with an open mind and a desire to truly make our city better.

Why are you interested in serving on the Parks and Community Services Commission? I care deeply about this community. My kids are 4, 6 and 8 and we intend to continue to raise them here throughout high school and beyond and that is my reason why. I believe in being involved in your community and this commission in particular speaks to me. I think I can bring a new perspective but also a level of understanding of the challenges that this commission might face. I am dedicated and excited about the opportunity to do more for our city.

In what organizations are you currently a member? Please list.

Dublin Little League - Board Member
Dublin Unified School District - Parcel Tax Committee and LCAP Committee Briarhill Swim Team - Board Member
Murray Elementary School - PFC Co-President
What knowledge do you have of the City-owned community facilities in Dublin, such as the Dublin Senior Center, Shannon Community Center, or The Wave? Have you or a family member rented facilities with the City of Dublin? I am very familiar with the Shannon Community Center in particular. I have reserved Shannon on a few occasions for various events in the last few years. I am aware of the Senior Center and The Wave but have not rented them.

How can the City provide better equity and inclusion to all persons that use our parks, trails, and facilities, and access our programs? I would love to see the city out in the community more and bring the information to the community, as a true partner with city organizations. Outside of flyers/activity guides we receive, there doesn't seem to be a ton of information about what is going on, which automatically limits people that have access.
81 82
Emerald Glen Park. etc.

How do you feel about user fees for recreation programs and park/facility reservations? I think those user fees are reasonable and necessary in order for us to provide all the residents in Dublin with more recreation programs continuously, and better park/facility to make our city a great place to live in California.

How do you feel about making a decision for the overall good of the community but unpopular with neighbors, residents, or organizations?
If the decision is good for the community but unpopular with neighbors, residents or organizations, I would consider the long-term impact of the decision of the community, and I will do my best to keep an effective communication with the community members and organizations to ensure that my communicate the reasons for my decision clearly and transparently to the community. Of course, I will also get input from the community to understand their perspectives and concerns; in addition, I will explore compromise solutions or alternative approaches which may create a win-win situation in the future.

What is the most important contribution you can make as a member of the Parks and Community Services Commission? The most important contribution I can make as a member of the Parks and Community Services Commission is to act as a dedicated steward of community well-being, advocating for and shaping policies and programs that enhance the quality of life for residents; to act as a bridge between the community and local government by engaging with residents to understand their needs, preferences and concerns related to parks and community services.

Why are you interested in serving on the Parks and Community Services Commission? As 13 years resident living in Dublin, I love to contribute myself to our community services to promote community well-being. And, as a 15+ years real estate brokerage owner in bay area, I believe that the commission roles offer opportunities for leadership development. Therefore, in the past few years, I had volunteered actively in our community in Dublin. In the past, I served in Dublin school district budget committee, and served in Dublin High School and Dougherty Elementary as a school site council member, and a vice-president of PFC in Dougherty Elementary as well.

In what organizations are you currently a member? Please list.

I am a member of Bay East Association of Realtors, a member of California Association of Realtors, a member of National Association of Realtors; plus, I also joined the Rotary Club of Dublin.

What knowledge do you have of the City-owned community facilities in Dublin, such as the Dublin Senior Center, Shannon Community Center, or The Wave? Have you or a family member rented facilities with the City of Dublin? The Dublin Senior Center is the best meeting place for all the seniors, and it provides them with different classes as well; and Shannon Community Center is the place providing everybody in Dublin with a banquet hall, a full catering kitchen, preschool classrooms, meeting rooms which can be rented by residents. My own kids used to attend preschool classes in Shannon Community Center, and swimming classes in The Wave many years ago.

How can the City provide better equity and inclusion to all persons that use our parks, trails, and facilities, and access our programs? First of all, we need to ensure that all parks, trails, and facilities are designed and maintained with inclusivity in mind; and we shall ask for input and feedback from our community to better understand all the community members' needs and preferences; and then, we shall offer a wide range of programs that cater to various age groups, interests, and cultural backgrounds. Of course, we will also ensure that programs are affordable and accessible to all community members.
83 STAFF REPORT

CITY COUNCIL

Agenda Item 5.4
DATE: January 9, 2024
TO: Honorable Mayor and City Councilmembers
FROM: Linda Smith, City Manager
SUBJECT: Adoption of the Tri-Valley Hazard Mitigation Plan Prepared by: Jordan Foss, Management Analyst II
EXECUTIVE SUMMARY:

The City Council will consider adoption of the Tri-Valley Hazard Mitigation Plan. The Plan includes a thorough hazard risk assessment, disaster mitigation priorities, and subsequent mitigation actions and projects for the cities of Dublin, Livermore, and Pleasanton, and Dublin San Ramon Services District.

STAFF RECOMMENDATION:

Adopt the Resolution Approving in its Entirety Volume I and the Relevant Portions of Volume II Including the Introduction, City of Dublin Annex, and Appendices of the Tri-Valley Hazard Mitigation Plan.

FINANCIAL IMPACT:

None.

DESCRIPTION:

The Disaster Mitigation Act of 2000 created a framework for local governments to engage in multijurisdictional hazard mitigation planning and be eligible for certain kinds of related federal funding. Accordingly, in 2005, the City of Dublin joined the Association of Bay Area Government’s hazard mitigation planning process which yielded a regional mitigation plan. Since 2018, Dublin has partnered with cities of Livermore and Pleasanton, as well as Dublin San Ramon Services District (DSRSD), to pool resources for the creation of a hazard mitigation strategy specific to the Tri-Valley area.

In January 2022, the partner agencies, with the guidance of the consulting firm Tetra Tech, began preparing and developing an update to the Tri-Valley Hazard Mitigation Plan. The result of the organizational effort is a multi-jurisdictional, multi-hazard mitigation plan that was approved by 84

the Federal Emergency Management Agency (FEMA) in December 2023. This is the fourth comprehensive update to the initial mitigation plan, with previous approvals by FEMA in November 2005, February 2012, and March 2018. With City Council adoption of the Plan, Dublin and the participating jurisdictions will be eligible to apply for and receive grant funding from FEMA to reduce the vulnerability of affected residents.

Plan Overview
The hazard identification and profiling in the Plan addresses the following hazards of concern within the planning area:

1. Dam Failure

2. Drought

3. Earthquake

4. Flood

5. Landslide

6. Severe Weather

7. Wildfire
Climate change is incorporated as a summary assessment of current and anticipated impacts for each identified hazard of concern.

With the exception of dam failure, the Plan does not provide a full risk assessment of humancaused hazards. However, brief, qualitative discussions of the following hazards of interest are included: terrorism, cyber threats, hazardous materials release, pipeline and tank failure, and airline incidents.

Plan Goals
The goals of the Tri-Valley Hazard Mitigation Plan are to:

1. Ensure that hazards are identified and considered in land use decisions.

2. Improve local emergency management capability.

3. Promote community awareness, understanding, and interest in hazard mitigation policies and programs.

4. Incorporate hazard mitigation as an integrated public policy and standard practice.

5. Reduce community exposure and vulnerability to hazards where the greatest risk exists.

6. Increase resilience of infrastructure and critical facilities.

7. Promote an adaptive and resilient planning area that responds proactively to future conditions.

8. Develop and implement mitigation strategies that identify the best alternative to protect natural resources, promote equity, and use public funds in an efficient and cost-effective manner.

9. Prioritize and direct resources to increase disaster resiliency among historically underserved populations, individuals with access and functional needs, and in communities disproportionately impacted by disasters.

The participating local jurisdictions (known as the Planning Partners) assisted in the development 85

of the hazard and the vulnerability assessments and the mitigation action strategies for their respective jurisdictions and organizations. Each jurisdiction has been responsible for the review and approval of their individual sections of the Plan. Additionally, the Plan has been aligned with the goals, objectives, and priorities of California’s multi-hazard mitigation plan.

The Tri-Valley Hazard Mitigation Plan comprises two volumes. Volume I includes all federally required elements of a disaster mitigation plan that apply to the entire planning process, public involvement strategy, goals and objectives, planning area hazard risk assessment, planning area mitigation actions, and a plan maintenance strategy. Volume II provides all federally required jurisdiction-specific elements, included as annexes to the Plan.

The Plan was submitted to California Office of Emergency Services (CalOES) for review on October 12, 2023 (Attachment 3). CalOES completed its review and submitted the plan to FEMA for its review on October 31, 2023. On December 15, 2023 (Attachment 4), FEMA completed its review and determined that the plan meets the requirements of the Disaster Management Act and is eligible for final approval pending its adoption by each of the Planning Partners. For multijurisdictional plans such as Dublin’s, FEMA will issue multiple approvals as each Planning Partner submits its resolution formally adopting the Tri-Valley Hazard Mitigation Plan.

STRATEGIC PLAN INITIATIVE:

None.

NOTICING REQUIREMENTS/PUBLIC OUTREACH:

The City Council Agenda was posted.

ATTACHMENTS:
1) Resolution Approving in its Entirety Volume I and the Relevant Portions of Volume II Including the Introduction, City of Dublin Annex, and Appendices of the Tri-Valley Hazard Mitigation Plan
2) Exhibit A to the Resolution – Tri-Valley Hazard Mitigation Plan 3) CalOES Letter dated October 12, 2023
4) FEMA Letter dated December 15, 2023
86 Attachment I
Reso. No. XX-24, Item X.X, Adopted 01/09/2024 Page 1 of 2 RESOLUTION NO. XX – 24

A RESOLUTION OF THE CITY COUNCIL

OF THE CITY OF DUBLIN

ADOPTING IN ITS ENTIRETY VOLUME I AND THE RELEVANT PORTIONS OF VOLUME II

INCLUDING THE INTRODUCTION, CITY OF DUBLIN ANNEX, AND APPENDICES OF THE

TRI-VALLEY HAZARD MITIGATION PLAN
WHEREAS, all of the Tri-Valley area has exposure to natural hazards that increase the risk to life, property, environment and the City and County’s economy; and WHEREAS, proactive mitigation of known hazards before a disaster event can reduce or eliminate long-term risk to life and property; and
WHEREAS, the federal Disaster Mitigation Act of 2000 (Public Law 106-390) established new requirements for pre- and post-disaster hazard mitigation programs; and WHEREAS, a coalition of Tri-Valley Cities and Special Districts with like planning objectives was formed to pool resources together and create consistent mitigation strategies within the Tri-Valley area; and
WHEREAS, the coalition has completed a planning process that engages the public, assesses the risk and vulnerability to the impacts of natural hazards, develops a mitigation strategy consistent with a set of uniform goals and objectives, and creates a plan for implementing, evaluating, and revising this strategy.

NOW, THEREFORE, BE IT RESOLVED that the City Council of the City of Dublin:

1. Adopts in its entirety, Volume I and the relevant portions of Volume II including the Introduction, City of Dublin Annex and Appendices, of the Tri-Valley Hazard Mitigation Plan (HMP) attached hereto as Exhibit A to this Resolution.

2. Will use the adopted and approved portions of the Tri-Valley HMP to guide pre- and post-disaster mitigation of the hazards identified.

3. Will coordinate the strategies identified in the Tri-Valley HMP with other planning programs and mechanisms under its jurisdictional authority.

4. Will continue its support of the Steering Committee and continue to participate in the Planning Partnership as described by the Tri-Valley HMP.

5. Will help to promote and support the mitigation successes of all Tri-Valley HMP Planning Partners.
87 Reso. No. XX-24, Item X.X, Adopted XX/XX/2024 Page 2 of 2 PASSED, APPROVED AND ADOPTED this 9th day of January 2024, by the following vote:

AYES:

NOES:

ABSENT:

ABSTAIN:
______________________________
Mayor
ATTEST:
_________________________________
City Clerk
88 Volume 1
Planning Area-Wide Elements

TRI-VALLEY

LOCAL HAZARD MITIGATION PLAN
Agency Review Draft
October 2023
Attachment 2
Exhibit A to
the Resolution
89 90
Tri-Valley Local Hazard Mitigation Plan
Volume 1—Planning-Area-Wide Elements
October 2023

PREPARED FOR
City of Dublin, CA City of Livermore, CA City of Pleasanton, CA Dublin San Ramon Services District 100 Civic Plaza
Dublin, CA 94568
1052 S. Livermore Avenue
Livermore, CA 94550
123 Main Street
Pleasanton, CA 94566
7051 Dublin Blvd.

Dublin, CA 94568

PREPARED BY
Tetra Tech
1999 Harrison Street
Suite 500
Oakland, CA 94612
Phone: (510) 302-6300
Fax: (510) 433-0830
tetratech.com
Tetra Tech Project #103S8169
\\tt.local\gfs\USVolume2\Legacy\tts121fs1\EMI\Data\EMCR_Projects\California\Tri-Valley\HMP_2022_103s8169\Plan Development\Plan Documents\2023-07 Revised Submission Draft\2023-10_HMP Volume 1 _Tri-Valley_Revised SubmissionDraft.docx 91 92
v

CONTENTS
Executive Summary.............................................................................................................. xix PART 1— PLANNING PROCESS AND COMMUNITY PROFILE

1. Introduction to Hazard Mitigation Planning ................................................................................................ 1-1

1.1 Why Prepare This Plan? ...................................................................................................................... 1-1

1.2 Who Will Benefit From This Plan?..................................................................................................... 1-2

1.3 Contents of This Plan .......................................................................................................................... 1-2

2. Plan Update—What Has Changed............................................................................................................... 2-1

2.1 Previous Plans ..................................................................................................................................... 2-1

2.2 Why Update?....................................................................................................................................... 2-2

2.3 The Updated Plan—What Is Different? .............................................................................................. 2-3

3. Plan Update Approach ................................................................................................................................. 3-1

3.1 Formation of the Planning Team......................................................................................................... 3-1

3.2 Defining Stakeholders......................................................................................................................... 3-1

3.3 The Steering Committee...................................................................................................................... 3-1

3.4 Establishment of the Planning Partnership.......................................................................................... 3-2

3.5 Defining the Planning Area ................................................................................................................. 3-3

3.6 Coordination with Stakeholders and Agencies.................................................................................... 3-3

3.7 Review of Existing Programs.............................................................................................................. 3-6

3.8 Public Involvement.............................................................................................................................. 3-7

3.9 Plan Development Chronology/Milestones....................................................................................... 3-13

4. Community Profile....................................................................................................................................... 4-1

4.1 Geographic Overview.......................................................................................................................... 4-1

4.2 Historical Overview ............................................................................................................................ 4-1

4.3 Physical Setting ................................................................................................................................... 4-3

4.4 Development Profile............................................................................................................................ 4-5

4.5 Demographics.................................................................................................................................... 4-12

4.6 Economy............................................................................................................................................ 4-16

5. Hazards of Concern...................................................................................................................................... 5-1

5.1 Major Past Hazard Events................................................................................................................... 5-1

5.2 Hazards Identified for Assessment in This Plan.................................................................................. 5-2

6. Relevant Laws, Ordinances and Programs .................................................................................................. 6-1

6.1 Relevant Federal and State Agencies, Programs and Regulations...................................................... 6-1

6.2 Local Plans, Reports and Codes.......................................................................................................... 6-5

6.3 Local Capability Assessment .............................................................................................................. 6-6

6.4 Opportunities for Integration and Expansion ...................................................................................... 6-8 PART 2— RISK ASSESSMENT

7. Risk Assessment Methodology.................................................................................................................... 7-1

7.1 Risk Assessment Tools........................................................................................................................ 7-1

7.2 Risk Assessment Approach ................................................................................................................. 7-3

7.3 Sources of Data Used in Modeling...................................................................................................... 7-4

7.4 Limitations........................................................................................................................................... 7-6 93 Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements vi

8. Dam Failure ................................................................................................................................................. 8-1

8.1 General Background............................................................................................................................ 8-1

8.2 Hazard Profile...................................................................................................................................... 8-3

8.3 Exposure.............................................................................................................................................. 8-7

8.4 Vulnerability...................................................................................................................................... 8-10

8.5 Future Trends in Development.......................................................................................................... 8-12

8.6 Scenario............................................................................................................................................. 8-14

8.7 Issues................................................................................................................................................. 8-14

9. Drought ........................................................................................................................................................ 9-1

9.1 General Background............................................................................................................................ 9-1

9.2 Hazard Profile...................................................................................................................................... 9-5

9.3 Exposure............................................................................................................................................ 9-15

9.4 Vulnerability...................................................................................................................................... 9-15

9.5 Future Trends in Development.......................................................................................................... 9-17

9.6 Scenario............................................................................................................................................. 9-17

9.7 Issues................................................................................................................................................. 9-17

10. Earthquake ............................................................................................................................................... 10-1

10.1 General Background........................................................................................................................ 10-1

10.2 Hazard Profile.................................................................................................................................. 10-6

10.3 Exposure........................................................................................................................................ 10-14

10.4 Vulnerability.................................................................................................................................. 10-17

10.5 Future Trends in Development...................................................................................................... 10-31

10.6 Scenario......................................................................................................................................... 10-31

10.7 Issues............................................................................................................................................. 10-31

11. Flood ........................................................................................................................................................ 11-1

11.1 General Background........................................................................................................................ 11-1

11.2 Hazard Profile.................................................................................................................................. 11-5

11.3 Exposure........................................................................................................................................ 11-15

11.4 Vulnerability.................................................................................................................................. 11-20

11.5 Future Trends in Development...................................................................................................... 11-26

11.6 Scenario......................................................................................................................................... 11-26

11.7 Issues............................................................................................................................................. 11-26

12. Landslide.................................................................................................................................................. 12-1

12.1 General Background........................................................................................................................ 12-1

12.2 Hazard Profile.................................................................................................................................. 12-3

12.3 Exposure.......................................................................................................................................... 12-7

12.4 Vulnerability.................................................................................................................................. 12-12

12.5 Future Trends in Development...................................................................................................... 12-14

12.6 Scenario......................................................................................................................................... 12-14

12.7 Issues............................................................................................................................................. 12-14

13. Severe Weather........................................................................................................................................ 13-1

13.1 General Background........................................................................................................................ 13-1

13.2 Hazard Profile.................................................................................................................................. 13-5

13.3 Exposure and Vulnerability............................................................................................................. 13-9

13.4 Future Trends in Development...................................................................................................... 13-12

13.5 Scenario......................................................................................................................................... 13-12 94 Contents
vii

13.6 Issues............................................................................................................................................. 13-12

14. Wildfire.................................................................................................................................................... 14-1

14.1 General Background........................................................................................................................ 14-1

14.2 Hazard Profile.................................................................................................................................. 14-2

14.3 Exposure.......................................................................................................................................... 14-6

14.4 Vulnerability.................................................................................................................................. 14-10

14.5 Future Trends in Development...................................................................................................... 14-13

14.6 Scenario......................................................................................................................................... 14-14

14.7 Issues............................................................................................................................................. 14-14

15. Climate Change........................................................................................................................................ 15-1

15.1 General Background........................................................................................................................ 15-1

15.2 Vulnerability Assessment................................................................................................................ 15-9

15.3 Issues............................................................................................................................................. 15-14

16. Public Health Emergency......................................................................................................................... 16-1

16.1 General Background........................................................................................................................ 16-1

16.2 Hazard Profile.................................................................................................................................. 16-3

16.3 Exposure and Vulnerability............................................................................................................. 16-5

16.4 Future Trends in Development........................................................................................................ 16-5

16.5 Scenario........................................................................................................................................... 16-5

16.6 Issues............................................................................................................................................... 16-5

17. Human-Caused Hazards........................................................................................................................... 17-1

17.1 General Background........................................................................................................................ 17-1

17.2 Hazard Profile................................................................................................................................ 17-12

17.3 Secondary Hazards........................................................................................................................ 17-20

17.4 Exposure........................................................................................................................................ 17-21

17.5 Vulnerability.................................................................................................................................. 17-23

17.6 Future Trends in Development...................................................................................................... 17-24

17.7 Scenario......................................................................................................................................... 17-24

17.8 Issues............................................................................................................................................. 17-25

18. Risk Ranking............................................................................................................................................ 18-1

18.1 Probability of Occurrence................................................................................................................ 18-1

18.2 Impact.............................................................................................................................................. 18-2

18.3 Risk Rating and Ranking................................................................................................................. 18-4 PART 3— MITIGATION STRATEGY

19. Goals and Objectives ............................................................................................................................... 19-1

19.1 Mission Statement ........................................................................................................................... 19-1

19.2 Goals................................................................................................................................................ 19-1

19.3 Objectives........................................................................................................................................ 19-2

20. Mitigation Best Practices and Adaptive Capacity.................................................................................... 20-1

20.1 Mitigation Best Practices................................................................................................................. 20-1

20.2 Adaptive Capacity ........................................................................................................................... 20-9

21. Plan Adoption and Maintenance .............................................................................................................. 21-1

21.1 Plan Adoption.................................................................................................................................. 21-1

21.2 Plan Maintenance Strategy .............................................................................................................. 21-1 References........................................................................................................................................................R-1 95 Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements viii
Appendices
Appendix A. Hazard Mitigation Survey Results
Appendix B. Summary of Federal and State Agencies, Programs and Regulations Appendix C. Risk Assessment Mapping Methodology
Appendix D. Plan Adoption Resolutions from Planning Partners Appendix E. Progress Report Template
Appendix F. Steering Committee Meeting Materials
Tables
Table 2-1. Plan Changes Crosswalk....................................................................................................................... 2-3 Table 3-1. Steering Committee Members............................................................................................................... 3-2 Table 3-2. Municipal and Special District Planning Partners................................................................................. 3-3 Table 3-3. Plan Development Chronology/Milestones ........................................................................................ 3-14 Table 4-1. Planning Area Building Counts by Occupancy Class........................................................................... 4-6 Table 4-2. Planning Area Replacement Value ....................................................................................................... 4-7 Table 4-3. Annual Population Data ...................................................................................................................... 4-12 Table 5-1. Presidential Disaster Declarations......................................................................................................... 5-1 Table 5-2. Tri-Valley Hazard Comparison with California State Hazards............................................................. 5-3 Table 6-1. Summary of Relevant Federal Agencies, Programs and Regulations................................................... 6-1 Table 6-2. Summary of Relevant State Agencies, Programs and Regulations....................................................... 6-3 Table 6-3. Integration of Hazard Mitigation Plan With Other Plans and Programs............................................... 6-8 Table 7-1. Risk Assessment Data Sources ............................................................................................................. 7-5 Table 8-1. State of California Downstream Hazard Potential Classification ......................................................... 8-2 Table 8-2. Del Valle Dam Characteristics.............................................................................................................. 8-4 Table 8-3. Patterson Dam Characteristics .............................................................................................................. 8-5 Table 9-1. State Drought Management Program.................................................................................................... 9-5 Table 9-2. Projected Normal Year Water Supply and Demand Comparison......................................................... 9-7 Table 9-3. Water Shortage Contingency Plan Levels............................................................................................. 9-8 Table 10-1. Mercalli Scale and Peak Ground Acceleration Comparison ............................................................. 10-3 Table 10-2. NEHRP Soil Classification System .................................................................................................. 10-6 Table 10-3. Recent Earthquakes Magnitude 4.0 or Larger Near Planning Area .................................................. 10-6 Table 10-4. Earthquake Probabilities for the San Francisco Bay Area, 2014-2043........................................... 10-10 Table 10-5. Earthquakes Modeled for Risk Assessment.................................................................................... 10-17 Table 10-6. Age of Structures in Planning Area ................................................................................................ 10-27 96 Contents
ix
Table 11-1. Jurisdictions and Date Joined NFIP .................................................................................................. 11-5 Table 11-2. Flood Insurance Statistics ................................................................................................................. 11-6 Table 11-3. CRS Community Status in the Planning Area .................................................................................. 11-6 Table 11-4. FEMA Disaster Declarations for Flood Events in Alameda County ................................................ 11-8 Table 11-5. Flood Events in the Tri-Valley Planning Area.................................................................................. 11-8 Table 11-6. Probability of Future Occurrences of Flood Events........................................................................ 11-12 Table 11-7. Summary of Peak Discharges within the Planning Area ................................................................ 11-13 Table 12-1. FEMA Landslide Disaster Declarations in Alameda County ........................................................... 12-3 Table 12-2. Landslide Events in the Tri-Valley Planning Area ........................................................................... 12-4 Table 13-1. Beaufort Wind Chart......................................................................................................................... 13-4 Table 13-2. Severe Weather Events in the Tri-Valley Planning Area.................................................................. 13-6 Table 14-1. Recent Fires Affecting Planning Area (Burning More Than 10 Acres)............................................ 14-3 Table 14-2. Record of Fire in Alameda County ................................................................................................... 14-5 Table 15-1. Summary of Likely Primary and Secondary Climate Change Impacts on the Planning Area.......... 15-5 Table 15-2. Average Temperature Projections in Tri-Valley Planning Area ....................................................... 15-6 Table 16-1. Naturally Spread Diseases Seen in California................................................................................... 16-2 Table 17-1. Common Mechanisms for Cyber-attacks.......................................................................................... 17-6 Table 17-2. Hazard Materials Spills in Tri-Valley Planning Area Reported to Cal OES (2012-2016) ............. 17-15 Table 17-3. Total Fatal and Injury Collision Data for Tri-Valley Planning Area .............................................. 17-16 Table 17-4. Injuries and Fatalities from Hazardous Materials Spills in Tri-Valley Planning Area ................... 17-20 Table 17-5. Criticality Factors............................................................................................................................ 17-22 Table 17-6. Vulnerability Criteria ...................................................................................................................... 17-22 Table 20-1. Alternatives to Mitigate the Dam Failure Hazard ............................................................................. 20-2 Table 20-2. Alternatives to Mitigate the Drought Hazard.................................................................................... 20-3 Table 20-3. Alternatives to Mitigate the Earthquake Hazard ............................................................................... 20-4 Table 20-4. Alternatives to Mitigate the Flood Hazard........................................................................................ 20-5 Table 20-5. Alternatives to Mitigate the Landslide Hazard ................................................................................. 20-6 Table 20-6. Alternatives to Mitigate the Severe Weather Hazard........................................................................ 20-7 Table 20-7. Alternatives to Mitigate the Wildfire Hazard.................................................................................... 20-8 Table 21-1. Plan Maintenance Matrix .................................................................................................................. 21-2 Figures
Figure 3-1. Hazard Mitigation Plan Web Site Homepage...................................................................................... 3-9 Figure 3-2. Hazard Mitigation Survey.................................................................................................................. 3-10 Figure 3-3. Tri-Valley StoryMap ......................................................................................................................... 3-11 Figure 3-4. Social Media Public Outreach ........................................................................................................... 3-12 Figure 4-1. Planning Area ...................................................................................................................................... 4-2 Figure 4-2. Watersheds and Water Bodies in the Planning Area ........................................................................... 4-4 Figure 4-3. Normal Precipitation and Temperatures in Planning Area, 2000-2023............................................... 4-5 97 Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements x
Figure 4-4. Critical Facilities (1 of 2)..................................................................................................................... 4-9 Figure 4-5. Critical Facilities (2 of 2)................................................................................................................... 4-10 Figure 4-6. Planning Area Critical Facilities by Jurisdiction and Category......................................................... 4-11 Figure 4-7. Residential Building Permit Trends, 2005 to 2021............................................................................ 4-11 Figure 4-8. Alameda County vs. Planning Area Population Growth ................................................................... 4-13 Figure 4-9. Planning Area Age Distribution ........................................................................................................ 4-15 Figure 4-10. Planning Area Race Distribution ..................................................................................................... 4-15 Figure 4-11. Industry in the Planning Area by Population Employed ................................................................. 4-17 Figure 4-12. Occupations in the Planning Area ................................................................................................... 4-18 Figure 4-13. California State and Planning Area Unemployment Rate ............................................................... 4-18 Figure 8-1. Combined Dam Failure Inundation ..................................................................................................... 8-6 Figure 8-2. Population Exposed to Dam Failure and Total City Population, by Jurisdiction ................................ 8-7 Figure 8-3. Number and Exposed Value of Buildings in Dam Failure Inundation Area ....................................... 8-8 Figure 8-4. Total Value in Dam Failure Inundation Area as % of Total Replacement Value, by Jurisdiction...... 8-8 Figure 8-5. Number of Structures within the Dam Failure Inundation Zone, by Occupancy Class....................... 8-9 Figure 8-6. Critical Facilities within the Dam Failure Inundation Area, by Jurisdiction ..................................... 8-10 Figure 8-7. Estimated Persons Displaced or Requiring Short-Term Shelter Due to Dam Failure ....................... 8-11 Figure 8-8. Loss Estimates for Dam Failure......................................................................................................... 8-13 Figure 8-9. Number of Buildings Impacted by Dam Failure................................................................................ 8-13 Figure 8-10. Estimated Structural Debris Generated by Dam Failure.................................................................. 8-13 Figure 8-11. Estimated Damage to Critical Facilities from Dam Failure............................................................. 8-14 Figure 9-1. Standard National Drought and Precipitation Indices ......................................................................... 9-3 Figure 9-2. Zone 7 Water Agency Supply and Use, Fiscal Year 2019-2020 ......................................................... 9-6 Figure 9-3. Records of Statewide Drought in California Since 2000................................................................... 9-10 Figure 9-4. Palmer Drought Severity Index, January 2023 .................................................................................. 9-13 Figure 9-5. U.S. Drought Monitor Map of Planning Area Drought Conditions, June 2023 ................................ 9-13 Figure 9-6. Percent of Alameda and Contra Cosa Counties Affected by Each USDM Rating, 2000 – 2023...... 9-14 Figure 10-1. Peak Acceleration (%g) with 2% Probability of Exceedance in 50 Years ...................................... 10-5 Figure 10-2. Recent Earthquakes Magnitude 5.0 or Larger Near Planning Area................................................. 10-7 Figure 10-3. Significant Known Faults in the Bay Area ...................................................................................... 10-9 Figure 10-4. NEHRP Soils Soil Classification................................................................................................... 10-11 Figure 10-5. Liquefaction Susceptibility ............................................................................................................ 10-12 Figure 10-6. PGA (as %g) with 10-Percent Probability of Exceedance in 50 Years ......................................... 10-13 Figure 10-7. Population Living on NEHRP D Soils and Total City Population, by Jurisdiction....................... 10-14 Figure 10-8. Number and Exposed Value of Buildings on NEHRP D Soils...................................................... 10-15 Figure 10-9. Total Value on NEHRP D Soils as Percent of Total Replacement Value, by Jurisdiction............ 10-15 Figure 10-10. Number of Structures on NEHRP D Soils, by Occupancy Class ................................................ 10-16 Figure 10-11. Critical Facilities on NEHRP D Soils, by Category and Jurisdiction.......................................... 10-17 Figure 10-12. Calaveras (No) M6.86 Earthquake Scenario ............................................................................... 10-18 Figure 10-13. Greenville (No) M6.86 Earthquake Scenario .............................................................................. 10-19 Figure 10-14. HayWired M7.05 Earthquake Scenario ....................................................................................... 10-20 Figure 10-15. Las Positas M6.5 Earthquake Scenario........................................................................................ 10-21 Figure 10-16. N. Mount Diablo Thrust South M6.5 Earthquake Scenario......................................................... 10-22 Figure 10-17. Estimated Number of Displaced Households Due to Earthquake ............................................... 10-24 Figure 10-18. Estimated Number of Persons Requiring Short-Term Shelter Due to Earthquake...................... 10-24 98 Contents
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Figure 10-19. Loss Estimates for Earthquake, Total Planning Area .................................................................. 10-25 Figure 10-20. Loss Estimates for Earthquake, City of Dublin ........................................................................... 10-25 Figure 10-21. Loss Estimates for Earthquake, City of Livermore ..................................................................... 10-25 Figure 10-22. Loss Estimates for Earthquake, City of Pleasanton ..................................................................... 10-26 Figure 10-23. Estimated Earthquake-Caused Debris ......................................................................................... 10-26 Figure 10-24. Critical Facility Damage Potential, Calaveras Fault Scenario..................................................... 10-27 Figure 10-25. Critical Facility Damage Potential, Greenville Fault Scenario.................................................... 10-28 Figure 10-26. Critical Facility Damage Potential, HayWired Fault Scenario .................................................... 10-28 Figure 10-27. Critical Facility Damage Potential, Las Positas Fault Scenario................................................... 10-28 Figure 10-28. Critical Facility Damage Potential, Mt. Diablo Fault Scenario ................................................... 10-29 Figure 10-29. Critical Facility Functionality, Calaveras Fault Scenario ............................................................ 10-29 Figure 10-30. Critical Facility Functionality, Greenville Fault Scenario........................................................... 10-29 Figure 10-31. Critical Facility Functionality, HayWired Fault Scenario ........................................................... 10-30 Figure 10-32. Critical Facility Functionality, Las Positas Fault Scenario.......................................................... 10-30 Figure 10-33. Critical Facility Functionality, Mt. Diablo Fault Scenario .......................................................... 10-30 Figure 11-1. FEMA Flood Hazard Areas........................................................................................................... 11-11 Figure 11-2. Area in the Flood Zone, by Jurisdiction and Flood Event ............................................................. 11-12 Figure 11-3. Population Exposed to Flood and Total City Population, by Jurisdiction ..................................... 11-15 Figure 11-4. Total Planning Area Population Exposed to Flood........................................................................ 11-15 Figure 11-5. Number and Exposed Value of Buildings in the 1% Annual Chance Flood Zone ........................ 11-16 Figure 11-6. Number and Exposed Value of Buildings in the 0.2% Annual Chance Flood Zone ..................... 11-16 Figure 11-7. Total Value in Flood Areas as Percent of Total Replacement Value, by Jurisdiction................... 11-17 Figure 11-8. Structures in the 1% Annual Chance Flood Zone, by Jurisdiction and Occupancy Class............. 11-17 Figure 11-9. Structures in the 0.2% Annual Chance Flood Zone, by Jurisdiction and Occupancy Class.......... 11-18 Figure 11-10. Critical Facilities in the 1-Percent Annual Chance Flood Zone, by Category and Jurisdiction .. 11-19 Figure 11-11. Critical Facilities in the 0.2-Percent Annual Chance Flood Zone, by Category and Jurisdiction 11-20 Figure 11-12. Estimated Number of Displaced Persons Due to Flood............................................................... 11-21 Figure 11-13. Estimated Number of Persons Requiring Short-Term Shelter Due to Flood............................... 11-21 Figure 11-14. Estimated Number of Buildings Impacted by Flood ................................................................... 11-22 Figure 11-15. Loss Estimates for Flood, Total Planning Area ........................................................................... 11-23 Figure 11-16. Loss Estimates for Flood, City of Dublin .................................................................................... 11-23 Figure 11-17. Loss Estimates for Flood, City of Livermore .............................................................................. 11-23 Figure 11-18. Loss Estimates for Flood, City of Pleasanton.............................................................................. 11-24 Figure 11-19. Estimated Flood-Caused Debris .................................................................................................. 11-24 Figure 11-20. Estimated Damage to Critical Facilities from 1% Annual Chance Flood ................................... 11-25 Figure 11-21. Estimated Damage to Critical Facilities from 0.2% Annual Chance Flood ................................ 11-25 Figure 12-1. Susceptibility to Deep-Seated Landslides........................................................................................ 12-5 Figure 12-2. Population Exposed to Landslide Hazard and Total City Population, by Jurisdiction .................... 12-7 Figure 12-3. Total Planning Area Population Exposed to Landslide Hazard....................................................... 12-7 Figure 12-4. Number and Exposed Value of Buildings in the Moderate Landslide Susceptibility Zone ............ 12-8 Figure 12-5. Number and Exposed Value of Buildings in the High Landslide Susceptibility Zone.................... 12-8 Figure 12-6. Number and Exposed Value of Buildings in the Very High Landslide Susceptibility Zone........... 12-9 Figure 12-7. Total Value in Landslide Susceptibility Zones as % of Total Replacement Value, by City ........... 12-9 Figure 12-8. Structures in the Moderate Landslide Susceptibility Zone, by Jurisdiction and Occupancy Class12-10 Figure 12-9. Structures in the High Landslide Susceptibility Zone, by Jurisdiction and Occupancy Class ...... 12-10 99 Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements xii
Figure 12-10. Structures in Very High Landslide Susceptibility Zone, by Jurisdiction and Occupancy Class . 12-11 Figure 12-11. Critical Facilities in the High or Very High Landslide Susceptibility Zone................................ 12-12 Figure 12-12. Loss Estimates for Landslide....................................................................................................... 12-13 Figure 13-1. National Weather Service Heat Index.............................................................................................. 13-3 Figure 13-2. Space Weather Phenomena.............................................................................................................. 13-5 Figure 13-3. Annual Number of Heat Advisories in Alameda and Contra Costa Counties Since 2006 .............. 13-8 Figure 13-4. Wind Zones in the United States ..................................................................................................... 13-9 Figure 13-5. Loss Estimates for Severe Weather ............................................................................................... 13-11 Figure 14-1. Wildfire Hazard Severity Zones...................................................................................................... 14-4 Figure 14-2. Population Exposed to Wildfire Hazard and Total City Population, by Jurisdiction ...................... 14-6 Figure 14-3. Total Planning Area Population Exposed to Wildfire Hazard......................................................... 14-6 Figure 14-4. Number and Exposed Value of Buildings in the Moderate FHSZ .................................................. 14-7 Figure 14-5. Number and Exposed Value of Buildings in the High FHSZ.......................................................... 14-7 Figure 14-6. Number and Exposed Value of Buildings in the Very High FHSZ................................................. 14-8 Figure 14-7. Total Value in FHSZs as Percent of Total Replacement Value, by Jurisdiction ............................. 14-8 Figure 14-8. Structures in the Moderate FHSZ, by Jurisdiction and Occupancy Class ....................................... 14-9 Figure 14-9. Structures in the High FHSZ, by Jurisdiction and Occupancy Class............................................... 14-9 Figure 14-10. Structures in the Very High FHSZ, by Jurisdiction and Occupancy Class.................................. 14-10 Figure 14-11. Critical Facilities in the High or Very High FHSZ...................................................................... 14-11 Figure 14-12. Loss Estimates for Wildfire ......................................................................................................... 14-12 Figure 15-1. Global Carbon Dioxide Concentrations Over Time ........................................................................ 15-1 Figure 15-2. Observed and Projected Average Temperatures in Tri-Valley Planning Area ................................ 15-6 Figure 15-3. Projected Number of Extreme Heat Days by Year.......................................................................... 15-7 Figure 15-4. Projected Changes in Fire Risk, Relative to 2010 Levels................................................................ 15-8 Figure 17-1. Example Pop-Up Message Indicating Ransomware Infection ........................................................ 17-7 Figure 17-2. Gas Transmission and Hazardous Liquid Pipelines Near the Planning Area ................................ 17-18 Figure 18-1. Probability Factors for Hazards of Concern .................................................................................... 18-2 Figure 18-2. Impact Factors for Hazards of Concern........................................................................................... 18-3 Figure 18-3. Weighted Impact Factors for Hazards of Concern .......................................................................... 18-3 Figure 18-4. Total Risk Rating for Hazards of Concern ...................................................................................... 18-4 Figure 18-5. Hazard Risk Ranking....................................................................................................................... 18-4 100
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ACKNOWLEDGMENTS
Planning Team
• Susan Frost, Special Projects Coordinator, City of Livermore – Project Lead • Jake Potter, Associate Planner, City of Livermore
• Shweta Bonn, Senior Planner, City of Pleasanton
• Diego Mora, Assistant Planner, City of Pleasanton
• John Stefanski, Assistant to the City Manager, City of Dublin (until July 2023) • Aaron Johnson, GIS Analyst, Dublin San Ramon Services District Consultants
• Rob Flaner, CFM, Tetra Tech, Inc., Project Manager
• Bart Spencer, CEM, Tetra Tech, Inc., Lead Project Planner • Carol Bauman, GISP, Tetra Tech, Inc., Risk Assessment Lead • Megan Brotherton, Tetra Tech, Inc., Planner
• Jake Poland, Tetra Tech, Inc., Planner
• Dan Portman, Tetra Tech, Inc., Technical Editor
Special Acknowledgments
The development of this plan would not have been possible without the dedication and commitment to this process by the Hazard Mitigation Plan Steering Committee. The dedication of the volunteer members of this committee to allocate their time to this process is greatly appreciated. Also, local citizens are commended for their participation in planning outreach activities. The success of the outreach effort will set the course for the successful implementation of this plan.
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Tri-Valley Local Hazard Mitigation Plan Definitions/Acronyms xiv

DEFINITIONS/ACRONYMS
ABAG—Association of Bay Area Governments
Acre-Foot—An acre-foot is the amount of water it takes to cover 1 acre to a depth of 1 foot. This measure is used to describe the quantity of storage in a water reservoir. An acre-foot is a unit of volume. One acre foot equals 7,758 barrels; 325,829 gallons; or 43,560 cubic feet. An average household of four will use approximately 1 acre-foot of water per year.

Asset—An asset is any man-made or natural feature that
has value, including people; buildings; infrastructure, such as bridges, roads, sewers, and water systems; lifelines, such as electricity and communication resources; and
environmental, cultural, or recreational features such as parks, wetlands, and landmarks.

Bank Erosion—Bank erosion refers to the erosion,
sloughing or undercutting of a river, stream or drain. It is natural for streams to meander through erosion
processes. Generally, bank erosion is a problem where
development has limited meandering, where streams have
been channelized, or where stream bank structures
(bridges, culverts, etc.) are in places where they can
cause damage to downstream areas. Stabilizing these
areas can help protect watercourses from sedimentation, prevent damage to adjacent lands, control unwanted
meander, and improve fish and wildlife habitat.

Base Flood—The flood having a 1% chance of being
equaled or exceeded in any given year, also known as the “100-year” or “1% chance” flood. The base flood is a
statistical concept used to ensure that all properties
subject to the National Flood Insurance Program (NFIP)
are protected to the same degree against flooding.

Basin—A basin is the area within which all surface
water—whether from rainfall, snowmelt, springs, or other sources—flows to a single water body or watercourse. The boundary of a river basin is defined by natural topography, such as hills, mountains, and ridges. Basins are also
referred to as “watersheds” and “drainage basins.”
Benefit/Cost Analysis—A benefit/cost analysis is a
systematic, quantitative method of comparing projected
benefits to projected costs of a project or policy. It is used as a measure of cost effectiveness.

Benefit—A benefit is a net project outcome and is usually defined in monetary terms. Benefits may include direct
and indirect effects. For the purposes of benefit-cost
analysis of proposed mitigation measures, benefits are
limited to specific, measurable, risk reduction factors, including reduction in expected property losses (buildings, contents, and functions) and protection of human life.

Building—A building is defined as a structure that is
walled and roofed, principally aboveground, and
permanently fixed to a site. The term includes
manufactured homes on permanent foundations on which
the wheels and axles carry no weight.

Capability Assessment—A capability assessment
provides a description and analysis of a community’s
current capacity to address threats associated with
hazards. The assessment includes two components: an
inventory of an agency’s mission, programs, and policies, and an analysis of its capacity to carry them out. A
capability assessment is an integral part of the planning process in which a community’s actions to reduce losses are identified, reviewed, and analyzed, and the framework for implementation is identified.

CCR—California Code of Regulations
CDBG-DR—Community Development Block Grant
Disaster Recovery
CEQA—California Environmental Quality Act
CFR—Code of Federal Regulations
Community Lifeline—The services, capabilities, and
physical assets that are used day-to-day to support a
community’s ongoing needs. When stabilized and working
properly, community lifelines enable all other aspects of society to function
Community Rating System (CRS)—The CRS is a
voluntary program under the NFIP that rewards
participating communities (provides incentives) for
exceeding the minimum requirements of the NFIP and
completing activities that reduce flood hazard risk by
providing flood insurance premium discounts.

Critical Facility—Facilities and infrastructure that are critical to the health and welfare of the population. For this plan, critical facilities are all physical assets identified as community lifelines
CRS—Community Rating System
Dam Failure—Dam failure refers to a partial or complete breach in a dam (or levee) that impacts its integrity. Dam failures occur for a number of reasons, such as flash
flooding, inadequate spillway size, mechanical failure of valves or other equipment, freezing and thawing cycles, earthquakes, and intentional destruction.

Dam—Any artificial barrier or controlling mechanism that can or does impound 10 acre-feet or more of water.

Debris Flow—Dense mixtures of water-saturated debris
that move down-valley; looking and behaving much like
flowing concrete. They form when loose masses of
unconsolidated material are saturated, become unstable, and move down slope. The source of water varies but
includes rainfall, melting snow or ice, and glacial outburst floods.
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Tri-Valley Local Hazard Mitigation Plan Definitions/Acronyms xv
DFIRM—Digital Flood Insurance Rate Maps
Disaster Mitigation Act of 2000 (DMA); The DMA is
Public Law 106-390 and is the latest federal legislation enacted to encourage and promote proactive, pre-disaster planning as a condition of receiving financial assistance under the Robert T. Stafford Act. The DMA emphasizes
planning for disasters before they occur. Under the DMA, a pre-disaster hazard mitigation program and new
requirements for the national post-disaster hazard
mitigation grant program were established.

DMA—Disaster Mitigation Act
Drainage Basin—A basin is the area within which all
surface water- whether from rainfall, snowmelt, springs or other sources- flows to a single water body or
watercourse. The boundary of a river basin is defined by natural topography, such as hills, mountains and ridges.

Drainage basins are also referred to as watersheds or
basins.

Drought—Drought is a period of time without substantial rainfall or snowfall from one year to the next. Drought can also be defined as the cumulative impacts of several dry years or a deficiency of precipitation over an extended period of time, which in turn results in water shortages for some activity, group, or environmental function. A
hydrological drought is caused by deficiencies in surface and subsurface water supplies. A socioeconomic drought
impacts the health, well-being, and quality of life or starts to have an adverse impact on a region. Drought is a
normal, recurrent feature of climate and occurs almost
everywhere.

DWR—Department of Water Resources
Earthquake—An earthquake is defined as a sudden slip
on a fault, volcanic or magmatic activity, and sudden
stress changes in the earth that result in ground shaking and radiated seismic energy. Earthquakes can last from a few seconds to over 5 minutes and have been known to
occur as a series of tremors over a period of several days.

The actual movement of the ground in an earthquake is
seldom the direct cause of injury or death. Casualties may result from falling objects and debris as shocks shake, damage, or demolish buildings and other structures.

EPA—U.S. Environmental Protection Agency
ESA—Endangered Species Act
Exposure—Exposure is defined as the number and dollar
value of assets considered to be at risk during the
occurrence of a specific hazard.

Extent—The range of anticipated intensities of a hazard, usually expressed using a scientific scale.

FEMA—Federal Emergency Management Agency
FERC—Federal Energy Regulatory Commission
Fire Behavior—Fire behavior refers to the physical
characteristics of a fire and is a function of the interaction between the fuel characteristics (such as type of
vegetation and structures that could burn), topography, and weather. Variables that affect fire behavior include the rate of spread, intensity, fuel consumption, and fire type (such as underbrush versus crown fire).

Fire Frequency—Fire frequency is the broad measure of
the rate of fire occurrence in a particular area. An estimate of the areas most likely to burn is based on past fire
history or fire rotation in the area, fuel conditions, weather, ignition sources (such as human or lightning), fire
suppression response, and other factors.

FIRM—Flood Insurance Rate Map
FIS—Flood Insurance Study
Flash Flood—A flash flood occurs with little or no warning when water levels rise at an extremely fast rate
Flood Insurance Rate Map (FIRM)—FIRMs are the
official maps on which the Federal Emergency
Management Agency (FEMA) has delineated the Special
Flood Hazard Area (SFHA).

Flood Insurance Study—A report published by the
Federal Insurance and Mitigation Administration for a
community in conjunction with the community’s Flood
Insurance Rate Map. The study contains such background
data as the base flood discharges and water surface
elevations that were used to prepare the FIRM. In most
cases, a community FIRM with detailed mapping will have a corresponding flood insurance study.

Floodplain—Any land area susceptible to being
inundated by flood waters from any source. A flood
insurance rate map identifies most, but not necessarily all, of a community’s floodplain as the Special Flood Hazard Area (SFHA).

Floodway—Floodways are areas within a floodplain that
are reserved for the purpose of conveying flood discharge without increasing the base flood elevation more than 1 foot. Generally speaking, no development is allowed in
floodways, as any structures located there would block the flow of floodwaters.

FRA—Federal Responsibility Area
Freeboard—Freeboard is the margin of safety added to
the base flood elevation.

Frequency—For the purposes of this plan, frequency
refers to how often a hazard of specific magnitude,
duration, and/or extent is expected to occur on average.

Statistically, a hazard with a 100-year frequency is
expected to occur about once every 100 years on average and has a 1 percent chance of occurring any given year.

Frequency reliability varies depending on the type of
hazard considered.

Geographic Information System (GIS)—GIS is a
computer software application that relates data regarding physical and other features on the earth to a database for mapping and analysis.

GIS—Geographic Information System
Goal—A goal is a general guideline that explains what is to be achieved. Goals are usually broad-based, long-term, 103
Tri-Valley Local Hazard Mitigation Plan Definitions/Acronyms xvi
policy-type statements and represent global visions. Goals help define the benefits that a plan is trying to achieve.

The success of a hazard mitigation plan is measured by
the degree to which its goals have been met (that is, by the actual benefits in terms of actual hazard mitigation).

Hazard—A hazard is a source of potential danger or
adverse condition that could harm people and/or cause
property damage.

Hazards U.S. Multi-Hazard Loss Estimation Program
(Hazus)—Hazus is a GIS-based program used to support
the development of risk assessments as required under
the DMA. The Hazus software program assesses risk in a
quantitative manner to estimate damage and losses
associated with natural hazards. Hazus is FEMA’s
nationally applicable, standardized methodology and
software program and contains modules for estimating
potential losses from earthquakes, floods, and wind
hazards. Hazus has also been used to assess vulnerability (exposure) for other hazards.

Hazus—Hazards, United States
Hydraulics—Hydraulics is the branch of science or
engineering that addresses fluids (especially water) in motion in rivers or canals, works and machinery for
conducting or raising water, the use of water as a prime mover, and other fluid-related areas.

Hydrology—Hydrology is the analysis of waters of the
earth. For example, a flood discharge estimate is
developed by conducting a hydrologic study.

Intensity—For the purposes of this plan, intensity refers to the measure of the effects of a hazard.

Inventory—The assets identified in a study region
comprise an inventory. Inventories include assets that
could be lost when a disaster occurs and community
resources are at risk. Assets include people, buildings, transportation, and other valued community resources.

Landslide—Landslides can be described as the sliding
movement of masses of loosened rock and soil down a
hillside or slope. Fundamentally, slope failures occur when the strength of the soils forming the slope exceeds the pressure, such as weight or saturation, acting upon them.

Lightning—Lightning is an electrical discharge resulting from the buildup of positive and negative charges within a thunderstorm. When the buildup becomes strong enough,
lightning appears as a “bolt,” usually within or between clouds and the ground. A bolt of lightning instantaneously reaches temperatures approaching 50,000ºF. The rapid
heating and cooling of air near lightning causes thunder.

Lightning is a major threat during thunderstorms.

Liquefaction—Liquefaction is the complete failure of
soils, occurring when soils lose shear strength and flow horizontally. It is most likely to occur in fine grain sands and silts, which behave like viscous fluids when
liquefaction occurs. This situation is extremely hazardous to development on the soils that liquefy, and generally results in extreme property damage and threats to life and safety.

Local Government—Any county, municipality, city, town,
township, public authority, school district, special district, intrastate district, council of governments (regardless of whether the council of governments is incorporated as a nonprofit corporation under State law), regional or
interstate government entity, or agency or instrumentality of a local government; any Indian tribe or authorized tribal organization, or Alaska Native village or organization; and any rural community, unincorporated town or village, or other public entity.

LRA—Local Responsibility Area
Magnitude—Magnitude is the measure of the strength of
an earthquake and is typically measured by the Richter
scale. As an estimate of energy, each whole number step in the magnitude scale corresponds to the release of
about 31 times more energy than the amount associated
with the preceding whole number value.

Mass movement—A collective term for landslides, debris
flows, sinkholes and lahars.

Mean Return Period—This term refers to the average
period of time in years between occurrences of a particular hazard (equal to the inverse of the annual frequency of occurrence).

Mitigation Action—Mitigation actions are specific actions to achieve goals and objectives that minimize the effects from a disaster and reduce the loss of life and property.

Mitigation—A preventive action that can be taken in
advance of an event that will reduce or eliminate the risk to life or property.

NEHRP—National Earthquake Hazards Reduction
Program
NFIP—National Flood Insurance Program
NIMS—National Incident Management System
NOAA—National Oceanic and Atmospheric Administration
NWS—National Weather Service
Objective—For the purposes of this plan, an objective is defined as a short-term aim that, when combined with
other objectives, forms a strategy or course of action to meet a goal. Unlike goals, objectives are specific and
measurable.

OES—Office of Emergency Services
Peak Ground Acceleration—Peak Ground Acceleration
(PGA) is a measure of the highest amplitude of ground
shaking that accompanies an earthquake, based on a
percentage of the force of gravity.

PGA—Peak Ground Acceleration
PHMSA—Pipeline and Hazardous Materials Safety
Administration
Preparedness—Preparedness refers to actions that
strengthen the capability of government, citizens, and
communities to respond to disasters.
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Tri-Valley Local Hazard Mitigation Plan Definitions/Acronyms xvii
Presidential Disaster Declaration—These declarations
are typically made for events that cause more damage
than state and local governments and resources can
handle without federal government assistance. Generally, no specific dollar loss threshold has been established for such declarations. A Presidential Disaster Declaration puts into motion long-term federal recovery programs, some of which are matched by state programs, designed to help
disaster victims, businesses, and public entities.

Probability of Occurrence—The probability of
occurrence is a statistical measure or estimate of the
likelihood that a hazard will occur. This probability is generally based on past hazard events in the area and a forecast of events that could occur in the future. A
probability factor based on yearly values of occurrence is used to estimate probability of occurrence.

Repetitive Loss Property—Any NFIP-insured property
that, since 1978 and regardless of any changes of
ownership during that period, has experienced: Four or
more paid flood losses in excess of $1000.00; or two paid flood losses in excess of $1000.00 within any 10-year
period since 197;8 or three or more paid losses that equal or exceed the current value of the insured property.

Risk Assessment—Risk assessment is the process of
measuring potential loss of life, personal injury, economic injury, and property damage resulting from hazards. This process assesses the vulnerability of people, buildings, and infrastructure to hazards and focuses on (1) hazard identification; (2) impacts of hazards on physical, social, and economic assets; (3) vulnerability identification; and (4) estimates of the cost of damage or costs that could be avoided through mitigation.

Risk Ranking—This ranking serves two purposes, first to describe the probability that a hazard will occur, and
second to describe the impact a hazard will have on
people, property, and the economy. Risk estimates are
based on the methodology used to prepare the risk
assessment for this plan.

Risk—Risk is the estimated impact that a hazard would
have on people, services, facilities, and structures in a community. Risk measures the likelihood of a hazard
occurring and resulting in an adverse condition that
causes injury or damage. Risk is often expressed in
relative terms such as a high, moderate, or low likelihood of sustaining damage above a particular threshold due to occurrence of a specific type of hazard. Risk also can be expressed in terms of potential monetary losses
associated with the intensity of the hazard.

Riverine—Of or produced by a river. Riverine floodplains have readily identifiable channels. Floodway maps can
only be prepared for riverine floodplains.

Robert T. Stafford Act—The Robert T. Stafford Disaster
Relief and Emergency Assistance Act (Public
Law 100-107) was signed into law on November 23, 1988.

This law amended the Disaster Relief Act of 1974 (Public Law 93-288). The Stafford Act is the statutory authority for most federal disaster response activities, especially as they pertain to FEMA and its programs.

SEMS—Standardized Emergency Management System
SFHA—Special Flood Hazard Area
Special Flood Hazard Area—The base floodplain
delineated on a Flood Insurance Rate Map. The SFHA is
mapped as a Zone A in riverine situations and zone V in coastal situations. The SFHA may or may not encompass
all of a community’s flood problems
SRA—State Responsibility Area
Stakeholder—Business leaders, civic groups, academia,
non-profit organizations, major employers, managers of
critical facilities, farmers, developers, special purpose districts, and others whose actions could impact hazard mitigation.

Steep Slope—Different communities and agencies define
it differently, depending on what it is being applied to, but generally a steep slope is a slope in which the percent slope equals or exceeds 25%. For this study, steep slope is defined as slopes greater than 33 percent.

Thunderstorm—A thunderstorm is a storm with lightning
and thunder produced by cumulonimbus clouds.

Thunderstorms usually produce gusty winds, heavy rains, and sometimes hail. Thunderstorms are usually short in
duration (seldom more than 2 hours). Heavy rains
associated with thunderstorms can lead to flash flooding during the wet or dry seasons.

Tornado—A tornado is a violently rotating column of air extending between and in contact with a cloud and the
surface of the earth. Tornadoes are often (but not always) visible as funnel clouds. On a local scale, tornadoes are the most intense of all atmospheric circulations, and winds can reach destructive speeds of more than 300 mph. A
tornado’s vortex is typically a few hundred meters in
diameter, and damage paths can be up to 1 mile wide and 50 miles long.

USGS—U.S. Geological Survey
Vulnerability—Vulnerability describes how exposed or
susceptible an asset is to damage. Vulnerability depends on an asset’s construction, contents, and the economic
value of its functions. Like indirect damage, the
vulnerability of one element of the community is often
related to the vulnerability of another. For example, many businesses depend on uninterrupted electrical power.

Flooding of an electric substation would affect not only the substation itself but businesses as well. Often, indirect effects can be much more widespread and damaging than
direct effects.

Watershed—A watershed is an area that drains
downgradient from areas of higher land to areas of lower land to the lowest point, a common drainage basin.

Wildfire—These terms refer to any uncontrolled fire
occurring on undeveloped land that requires fire
suppression. The potential for wildfire is influenced by three factors: the presence of fuel, topography, and air 105
Tri-Valley Local Hazard Mitigation Plan Definitions/Acronyms xviii
mass. Fuel can include living and dead vegetation on the ground, along the surface as brush and small trees, and in the air such as tree canopies. Topography includes both slope and elevation. Air mass includes temperature,
relative humidity, wind speed and direction, cloud cover, precipitation amount, duration, and the stability of the atmosphere at the time of the fire. Wildfires can be ignited by lightning and, most frequently, by human activity
including smoking, campfires, equipment use, and arson.

Windstorm—Windstorms are generally short-duration
events involving straight-line winds or gusts exceeding 50 mph. These gusts can produce winds of sufficient strength to cause property damage. Windstorms are especially
dangerous in areas with significant tree stands, exposed property, poorly constructed buildings, mobile homes
(manufactured housing units), major infrastructure, and aboveground utility lines. A windstorm can topple trees and power lines; cause damage to residential,
commercial, critical facilities; and leave tons of debris in its wake.

Zoning Ordinance—The zoning ordinance designates
allowable land use and intensities for a local jurisdiction.

Zoning ordinances consist of two components: a zoning
text and a zoning map.
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EXECUTIVE SUMMARY

HAZARD MITIGATION OVERVIEW
Hazard mitigation is the use of policies, programs, projects, and other activities to alleviate the death, injury, and property damage that can result from a disaster. The Cities of Dublin, Livermore, and Pleasanton, along with the Dublin San Ramon Services District (the Tri-Valley Planning Partnership), have collaborated to develop a hazard mitigation plan to reduce risks from natural disasters that complies with federal requirements for hazard mitigation planning.

In 2010, the Tri-Valley planning partners used hazard mitigation planning tools created by the Association of Bay Area Governments (ABAG) to meet their federal hazard mitigation planning requirements. In 2017, the TriValley Planning Partnership formed to prepare an updated multi-jurisdiction hazard mitigation plan that best suits local needs and capabilities. The planning partners developed a new plan from scratch, using lessons learned from the earlier ABAG planning efforts. The resulting 2018 plan was an update for each member of the Tri-Valley Planning Partnership.

Federal regulations require periodic updates of hazard mitigation plans. A jurisdiction covered by a plan that has expired is ineligible for certain federal natural disaster assistance funding. The 2023 Tri-Valley Local Hazard Mitigation Plan meets the federal update requirements while keeping the participating jurisdictions prepared to address their hazard mitigation needs in response to always changing local conditions.

PLAN DEVELOPMENT APPROACH
Organize, Review and Engage the Public
A planning team assembled for the plan update conducted outreach to invite the participation of local planning partners. A 15-member steering committee was assembled to oversee the plan update, consisting of staff from each of the planning partners, citizens, and other stakeholders in the defined planning area. Coordination with other county, state, and federal agencies involved in hazard mitigation occurred throughout the plan update process.

The planning team implemented a public involvement strategy developed by the Steering Committee. The strategy included public meetings to present the risk assessment and the draft plan, a hazard mitigation survey, a project website, and multiple media releases. The planning team and Steering Committee also reviewed the existing hazard mitigation plan, the California statewide hazard mitigation plan, and existing programs that may support hazard mitigation actions.
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Assemble, Adopt and Maintain the Plan
The planning team and Steering Committee assembled a document to meet federal hazard mitigation planning requirements. A mitigation plan review crosswalk included in the hazard mitigation plan demonstrates its compliance with all requirements. The planning partners will formally adopt the plan once the State of California Governor’s Office of Emergency Services and FEMA Region IX have granted pre-adoption approval.

The plan includes a schedule for monitoring and evaluating plan progress periodically and producing a revised plan every five years. This maintenance strategy also includes processes for continuing public involvement and integrating with other programs that can support or enhance hazard mitigation.

RISK ASSESSMENT
Risk assessment is the process of measuring the potential loss of life resulting from natural hazards, as well as personal injury, economic injury and property damage. It is used to define the vulnerability of people, buildings, and infrastructure to natural hazards. For this update, risk assessment models were enhanced with new data and technologies. The Steering Committee used the risk assessment to rank risk and to gauge the potential impacts of each hazard of concern in the Tri-Valley planning area. The risk assessment included the following:
• Hazard identification and profiling
• Assessment of the impact of hazards on physical, social, and economic assets • Identification of particular areas of vulnerability
• Estimates of the cost of potential damage.

Based on the risk assessment, hazards were ranked for the risk they pose to the overall planning area, as shown in Figure ES-1.

Figure ES-1. Planning-Area-Wide Hazard Risk Rating
Earthquake
36 Flood
18 Landslide
18 Severe Weather
33 Dam Failure
12 Drought
9 Wildfire
12 0
1 2
3 4
0 1 2 3 4 5 6 7 8
Values shown are risk rating. Larger circles indicate higher rating.

Highest
Risk
Medium
Risk
Lowest
Risk
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Each planning partner also ranked hazards for its own area. Figure ES-2 summarizes all jurisdictions’ numerical ratings of high, medium and low. The results indicate the following general patterns:
• The earthquake hazard was most commonly ranked as high. • The severe weather, wildfire and landslide hazards were most commonly ranked as medium. • The dam failure, flood and drought hazards were most commonly ranked as low.

Figure ES-2. Summary of Risk Rating for Individual Planning Partners

MISSION STATEMENT, GOALS AND OBJECTIVES
The Steering Committee developed the following mission statement for the 2023 planning effort:

Through community partnerships, establish a plan to reduce the vulnerability to hazards in order to protect the health, safety, welfare, environment and economy of the planning area.

The Steering Committee established the following goals for the plan update:

1. Ensure that hazards are identified and considered in land use decisions.

2. Improve local emergency management capability.

3. Promote community awareness, understanding, and interest in hazard mitigation policies and programs.

4. Incorporate hazard mitigation as an integrated public policy and standard practice.

5. Reduce community exposure and vulnerability to hazards where the greatest risk exists.

6. Increase resilience of infrastructure and critical facilities.

7. Promote an adaptive and resilient planning area that responds proactively to future conditions.

8. Develop and implement mitigation strategies that identify the best alternative to protect natural resources, promote equity, and use public funds in an efficient and cost-effective manner. 0 0
4 0 0 0
1 1
0 0 0
3 4
0 3
4 0
4 1
0 3
0 0.5
1 1.5
2 2.5
3 3.5
4 4.5
5 Dam Failure Drought Earthquake Flood Landslide Severe Weather Wildfire Number of Parters Assigning This Rating to This
Hazard
Highest Risk
Medium Risk
Lowest Risk
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9. Prioritize and direct resources to increase disaster resiliency among historically underserved populations, individuals with access and functional needs, and in communities disproportionately impacted by disasters.

Each selected objective meets multiple goals, serving as a stand-alone measurement of the effectiveness of a mitigation action, rather than as a subset of a goal. The objectives also are used to help establish priorities. The objectives are as follows:

1. Develop and provide updated information to improve the understanding of the locations, potential impacts, and linkages among threats, hazards, vulnerability, and measures needed to protect life safety health, property and the environment.

2. Use local general plan, zoning, and subdivision requirements to help establish resilient and sustainable communities.

3. Increase public participation in systems that provide warning and emergency communications.

4. Encourage the retrofit of vulnerable structures in the planning area.

5. Consider programs that incentivize risk reduction.

6. Reduce repetitive property losses due to hazards by updating land use, design, and construction policies.

7. Continually build linkages and promote dialog about emergency management within the public and private sectors.

8. Incorporate risk reduction considerations in new and updated infrastructure and development plans to reduce the impacts of hazards.

9. Inform the public, including underrepresented and marginalized community groups, on the risk of exposure to hazards and ways to increase the public’s capability to prepare for, respond to, recover from, and mitigate the impacts of these events.

10. Identify projects that simultaneously reduce risk while increasing planning area resilience and sustainability.

11. Where feasible and cost-effective, research, develop, and promote adoption of building and development laws, regulations, and ordinances exceeding the minimum levels needed for life safety.

12. Encourage hazard mitigation measures that promote and enhance natural processes, minimize adverse impacts on the ecosystem, and promote social equity.

MITIGATION ACTION PLAN
The planning partnership selected a range of mitigation actions to work toward achieving the goals set forth in this plan update. The recommended mitigation actions are activities designed to reduce or eliminate losses resulting from natural hazards. The update process resulted in the identification of 60 mitigation actions for implementation by individual planning partners, as presented in Volume 2 of the hazard mitigation plan.

IMPLEMENTATION
The Steering Committee developed a plan implementation and maintenance strategy that includes mid-term progress reporting, a strategy for continued public involvement, a commitment to plan integration with other relevant plans and programs, and a recommitment from the planning partners to actively maintain the plan over the five-year performance period.

Full implementation of the recommendations of this plan will require time and resources. The measure of the plan’s success will be its ability to adapt to changing conditions. The Tri-Valley Planning Partnership will assume 110
Executive Summary
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responsibility for adopting the recommendations of this plan and committing resources toward implementation.

The framework established by this plan commits all planning partners to pursue actions when the benefits of a project exceed its costs. The planning partnership developed this plan with extensive public input, and public support of the actions identified in this plan will help ensure the plan’s success. 111
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PART 1—PLANNING PROCESS AND

COMMUNITY PROFILE
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1. INTRODUCTION TO HAZARD MITIGATION PLANNING

1.1 WHY PREPARE THIS PLAN?

1.1.1 Federal Guidance
Hazard mitigation is defined as any action taken to reduce or alleviate the loss of life, personal injury, and property damage that can result from a disaster. It involves long- and short-term actions implemented before, during and after disasters. Hazard mitigation activities include planning efforts, policy changes, programs, studies, improvement projects, and other steps to reduce the impacts of hazards.

The federal Disaster Mitigation Act (DMA) emphasizes planning for disasters before they occur. The DMA requires state and local governments to develop hazard mitigation plans as a condition for federal disaster grant assistance. Regulations developed to fulfill the DMA’s requirements are included in Title 44 of the Code of Federal Regulations (44 CFR). The long-term benefits of hazard mitigation planning include the following:
• An increased understanding of hazards in the local community • A more sustainable and disaster-resistant community
• Financial savings through partnerships that support planning and mitigation efforts • Focused use of limited resources on hazards that have the biggest impact on the communities • Reduced long-term impacts and damage to human health and structures, and reduced repair costs.

The responsibility for hazard mitigation lies with not only with local, state, and federal governments, but also with private property owners and commercial and institutional interests. The DMA encourages cooperation among state and local authorities in pre-disaster planning. The enhanced planning network called for by the DMA helps local governments to articulate accurate needs for mitigation, resulting in faster allocation of funding and more cost-effective risk-reduction projects.

The DMA also promotes sustainability in hazard mitigation. To be sustainable, hazard mitigation needs to incorporate sound management of natural resources and address hazards and mitigation in the largest possible social and economic context.

1.1.2 Local Concerns
In response to the requirements of the DMA, the cities of Dublin, Livermore and Pleasanton, California and the Dublin San Ramon Services District (DSRSD) have developed this multi-jurisdiction hazard mitigation plan. The three cities make up the incorporated area of the Alameda County portion of the Tri-Valley region, on the east side of the San Francisco Bay area. This multi-jurisdiction plan represents an update to each city’s component of 115
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the 2018 Tri-Valley Local Hazard Mitigation Plan. The three cities and the DSRSD prepared annexes for that previous hazard mitigation plan that were approved and adopted in 2018.

This 2023 Tri-Valley Local Hazard Mitigation Plan fulfills the five-year plan update requirement for these planning partners. It identifies resources, information, and strategies for reducing risk from natural hazards in the Tri-Valley planning area. Components of the hazard mitigation plan were selected because they meet a program requirement and because they best meet the needs of the planning partners (the cities and participating special district) and their citizens. One benefit of multi-jurisdictional planning is the ability to pool resources and eliminate redundant activities within a planning area that has uniform risk exposure and vulnerabilities. The Federal Emergency Management Agency (FEMA) encourages multi-jurisdictional planning under its guidance for the DMA.

The plan will help guide and coordinate mitigation activities throughout the planning area. It was developed to meet the following objectives:
• Meet or exceed requirements of the DMA.
• Enable all planning partners to continue using federal grant funding to reduce risk through mitigation. • Meet the needs of each planning partner as well as state and federal requirements. • Create a risk assessment that focuses on local hazards of concern. • Meet the planning requirements of the Federal Emergency Management Agency’s (FEMA’s) Community Rating System (CRS), allowing planning partners that participate in the CRS program to maintain or enhance their CRS classifications.
• Coordinate existing plans and programs so that high-priority projects to mitigate possible disaster impacts are funded and implemented.

1.2 WHO WILL BENEFIT FROM THIS PLAN?
All residents and businesses of the planning area are the ultimate beneficiaries of this hazard mitigation plan. The hazard mitigation plan reduces risk for those who live in, work in, and visit the planning area. It provides a viable planning framework for all foreseeable natural hazards. Participation in development of the hazard mitigation plan by key stakeholders helped ensure that outcomes will be mutually beneficial. The resources and background information in the plan are applicable across the planning area, and the plan’s goals and recommendations can lay groundwork for the development and implementation of local mitigation activities and partnerships.

1.3 CONTENTS OF THIS PLAN
This plan has been set up in two volumes so that jurisdiction-specific elements may be easily distinguished from those that apply to the whole planning area:
• Volume 1—Volume 1 includes all federally required elements of a disaster mitigation plan that apply to the entire planning area. This includes the description of the planning process, public involvement strategy, goals and objectives, planning area hazard risk assessment, and a plan maintenance strategy. • Volume 2—Volume 2 includes all federally required jurisdiction-specific elements in annexes for each participating jurisdiction. It includes a description of the participation requirements established by the 116

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Steering Committee, as well as instructions and templates that the partners used to complete their annexes.

Both volumes include elements required under federal guidelines. DMA compliance requirements are cited at the beginning of subsections as appropriate to demonstrate compliance. Appendices provided at the end of Volume 1 include information or explanations to support the main content of the plan (see table of contents for list of appendices).

All planning partners will adopt Volume 1 in its entirety, including the appendices, and at least the following parts of Volume 2: Part 1, and each partner’s jurisdiction-specific annex. 117
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2. PLAN UPDATE—WHAT HAS CHANGED

2.1 PREVIOUS PLANS

2.1.1 ABAG Planning Efforts
In 2004, ABAG led a regional effort to address hazard mitigation planning for jurisdictions in the San Francisco Bay Area. The ABAG process equipped local governments with a template and tools to complete individual planning processes for their jurisdictions, while pooling resources and eliminating redundant planning efforts.

Alameda County’s first annex to the ABAG hazard mitigation plan was developed and adopted in 2007. In 2010, ABAG conducted its second regional planning effort. Dublin, Livermore and Pleasanton participated in the 2010 planning process, along with Alameda County, other cities, and the Alameda County Water District including the Zone 7 Water Agency; these jurisdictions used the ABAG tools to achieve DMA compliance.

The single-jurisdiction annexes in the 2010 hazard mitigation plan, developed using the ABAG template and tools, contained the following components:
• Introduction
• Description of the local planning process
• Hazards and risk assessment
• Summary of the National Flood Insurance Program and repetitive loss properties • Mitigation goals, activities and priorities
• Regional mitigation strategies
• Incorporation of the plan into existing planning mechanisms • Description of the plan update process
• Exhibits to illustrate the planning process.

The Dublin Unified School District and the Livermore Valley Joint Unified School District did not participate in a ABAG hazard mitigation planning.

2.1.2 2018 Tri-Valley Hazard Mitigation Plan
In 2015, ABAG again provided tools for counties and cities in the Bay Area to revise their previous plans and annexes but decided not to revise the regional 2010 ABAG hazard mitigation plan. As a result, multiple counties and cities that participated in the previous ABAG hazard mitigation plan needed to undertake a planning process independently, or as part of a new partnership, in order to remain eligible for federal hazard mitigation assistance. 119
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Alameda County set out to develop a stand-alone plan focusing on unincorporated areas; Dublin, Livermore, Pleasanton, and the DSRSD pooled resources to develop the 2018 multi-jurisdictional hazard mitigation plan. The following factors were the basis for the Tri-Valley hazard mitigation planning effort:
• The planning area has significant exposure to numerous natural hazards. • Limited local resources make it difficult to be pre-emptive in risk reduction actions. Being able to leverage federal financial assistance was paramount to successful hazard mitigation in the area. • The planning partners wanted to be proactive in preparedness for the probable impacts of natural hazards.

Based on its assessment of the identified natural hazards, the 2018 plan included 73 mitigation actions for implementation by individual planning partners that addressed the following seven hazards of concern:
• Dam failure
• Drought
• Earthquake
• Flood
• Landslide
• Severe weather
• Wildfire

2.2 WHY UPDATE?

2.2.1 Federal Eligibility
Title 44 of the Code of Federal Regulations (44 CFR) stipulates that hazard mitigation plans must present a schedule for monitoring, evaluating, and updating the plan. This provides an opportunity to reevaluate recommendations, monitor the impacts of actions that have been accomplished, and determine if there is a need to change the focus of mitigation strategies. The Robert T. Stafford Act requires that jurisdictions have current hazard mitigation plans to pursue and receive federal funding.

2.2.2 Changes in Development
Hazard mitigation plan updates must be revised to reflect changes in development in the planning area since the previous plan was completed (44 CFR Section 201.6(d)(3)). The plan must describe changes in development in hazard-prone areas that increased or decreased vulnerability for each jurisdiction since the last plan was approved.

If no changes in development impacted the jurisdiction’s overall vulnerability, plan updates may validate the information in the previously approved plan. The intent of this requirement is to ensure that the mitigation strategy continues to address the risk and vulnerability of existing and potential development and takes into consideration possible future conditions that could impact vulnerability.

The planning area experienced an 18.1 percent increase in population from 2000 to 2010, an average growth of

1.81 percent per year. Between 2010 and 2020, the California Department of Finance estimates that the total populations of Dublin, Livermore and Pleasanton grew an additional 22.48 percent, to 241,646 (California Department of Finance 2023). Since DSRSD services Dublin, San Ramon, and surrounding areas, its population 120

2. Plan Update—What Has Changed
2-3
would have increased proportionally with that of the number of connections (water and wastewater). DSRSD made the necessary adjustments in delivery, service, and procedures to accommodate these increases and changes.

The City of San Ramon’s hazard profile is covered by the Contra Costa County Hazard Mitigation Plan (Contra Costa County 2018).

This plan update assumes that some new development triggered by the increase in population occurred in hazard areas. Because all such new development would have been regulated pursuant to local programs and codes, it is assumed that vulnerability did not increase, even if exposure did. Participating planning partners have adopted general plans, strategic plans, and emergency plans that govern land-use decisions and policymaking, as well as building codes and specialty ordinances based on state and federal mandates. A detailed analysis of development patterns in the planning area is provided in Section 4.4 and in the individual partner annexes in Volume 2.

2.2.3 Community Priorities
As noted in the annexes for each jurisdiction participating in this hazard mitigation plan (provided in Volume 2 of this plan), community priorities were reviewed for each jurisdiction to determine whether any had changed in a way that called for revisions to the hazard mitigation plan. No significant changes in community priorities were identified from the 2018 Hazard Mitigation Plan.

2.3 THE UPDATED PLAN—WHAT IS DIFFERENT?
The updated plan differs from the initial plan in a variety of ways. Table 2-1 indicates the major changes between the two plans as they relate to 44 CFR planning requirements.

Table 2-1. Plan Changes Crosswalk
44 CFR Requirement 2018 Plan Updated Plan (2023)

PLANNING PROCESS
§201.6(b): In order to develop a more
comprehensive approach to reducing the
effects of natural disasters, the planning
process shall include:
• 1. An opportunity for the public to comment
on the plan during the drafting stage and
prior to plan approval;
• 2. An opportunity for neighboring
communities, local and regional agencies
involved in hazard mitigation activities, and
agencies that have the authority to regulate
development, as well as businesses,
academia and other private and non-profit
interests to be involved in the planning
process; and
• 3. Review and incorporation, if appropriate,
of existing plans, studies, reports, and
technical information.

The planning process was overseen by a
planning team of staff from participating
jurisdictions and the planning consultant, and a
steering committee with representatives from
stakeholder organizations in or near the
planning area. The planning team maintained
contact with other stakeholder agencies to
apprise them of ongoing planning activities.

The planning team and steering committee
reviewed relevant documents and developed
and implemented a strategy for public
involvement. The strategy included a survey,
attendance at public events, a website, and a
public comment period for review of a draft
version of the plan.

Volume 1 Chapter 3 described the planning
process for the 2018 plan. Jurisdiction-specific
annexes in Volume 2 list each planning
partner’s specific planning resources that were
reviewed as part of the planning process.

The planning process was little changed
from that used for the 2018 plan. Inperson attendance at public events was reduced, but a stronger internet
presence was established using social
media and a StoryMap website.

Volume 1 Chapter 3 describes the
overall planning process for the 2023
plan.

Jurisdiction-specific annexes in
Volume 2 list each planning partner’s
specific public outreach activities
undertaken as part of the planning
process.
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44 CFR Requirement 2018 Plan Updated Plan (2023)

RISK ASSESSMENT
§201.6(c)(2): The plan shall include a risk
assessment that provides the factual basis for
activities proposed in the strategy to reduce
losses from identified hazards. Local risk
assessments must provide sufficient
information to enable the jurisdiction to identify
and prioritize appropriate mitigation actions to
reduce losses from identified hazards.

Volume 1 Part 2 presented a risk assessment
of 10 hazards of concern: dam failure, drought,
earthquake, flood, landslide, severe weather,
wildfire, human caused hazards, health
hazards, and climate change. These hazards
were profiled as they impact the Tri-Valley
planning area. Including a qualitative
assessment of human caused hazards and
health hazards provides a more complete
picture of the hazards facing the planning area.

The risk assessment methodology was
unchanged but most-current data was
used in the analyses. Volume 1 Part 2
describes the risk assessment for the
2023 plan.

The updated plan presents quantitative
risk assessment results in graphs rather
than tables to better display the relative
significance of the findings.
§201.6(c)(2)(i): [The risk assessment shall
include a] description of the … location and
extent of all natural hazards that can affect the
jurisdiction. The plan shall include information
on previous occurrences of hazard events and
on the probability of future hazard events.

Volume 1 Part 2 presented a risk assessment
of each hazard of concern. Each hazard
chapter included the following components:
• Hazard profile, including maps of extent and
location, historical occurrences, frequency,
severity, and warning time
• Secondary hazards
• Climate change impacts
• Exposure of people, property, critical
facilities and environment
• Vulnerability of people, property, critical
facilities and environment
• Future trends in development
• Scenarios
• Issues
The general presentation of hazard
profiles is unchanged from the 2018
plan. Updated data was used to
represent the most current information.

A new analysis of social vulnerability
was included, using the Centers for
Disease Control and Prevention’s Social
Vulnerability Index (see Section 4.5.2).

The confirmation of hazards to be
assessed included a review of all
hazards assessed in the California state
hazard mitigation plan, with an
explanation for why any of those are
omitted from this plan.
§201.6(c)(2)(ii): [The risk assessment shall
include a] description of the jurisdiction’s
vulnerability to the hazards described in
paragraph (c)(2)(i). This description shall
include an overall summary of each hazard
and its impact on the community
Vulnerability was assessed for all hazards of
concern. The Hazus computer model was
used for the dam failure, earthquake, and flood
hazards, incorporating local data sets. Sitespecific data on Steering Committee-identified critical facilities were entered into the Hazus
model. Vulnerability was assessed for other
hazards by applying varying damage
percentages to an asset inventory extracted
from Hazus.

The hazards evaluation and risk
assessment methodology for this plan
were unchanged, but most-current data
was used in the analyses.

The earthquake risk assessment
included a new analysis that assessed
the exposure of people and property on
earthquake-sensitive soils (see
Section 10.3).
§201.6(c)(2)(ii): [The risk assessment] must
also address National Flood Insurance
Program insured structures that have been
repetitively damaged floods
Dublin, Livermore and Pleasanton had no
identified Repetitive Loss or Severe Repetitive
Loss structures insured through the National
Flood Insurance Program at the time of the
2018 plan.

There is one repetitive loss property in
the current planning area. This is
discussed in Section 11.2.4.
§201.6(c)(2)(ii)(A): The plan should describe
vulnerability in terms of the types and numbers
of existing and future buildings, infrastructure,
and critical facilities located in the identified
hazard area.

A complete inventory of the numbers and
types of buildings exposed was generated for
each hazard of concern. The Steering
Committee defined and identified “critical
facilities” for the planning area, and these
facilities were inventoried by exposure.

Each hazard chapter provided a discussion on
future development trends.

The methodology for evaluating
buildings in the hazard area is
unchanged. Most-current data was used
in the analysis. Results are presented in
graphs rather than tables to better
display the relative significance of the
findings.
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44 CFR Requirement 2018 Plan Updated Plan (2023)
§201.6(c)(2)(ii)(B): [The plan should describe
vulnerability in terms of an] estimate of the
potential dollar losses to vulnerable structures
identified in paragraph (c)(2)(i)(A) and a
description of the methodology used to
prepare the estimate.

Loss estimations in terms of dollar loss were
generated for all hazards of concern. These
estimates were generated by Hazus for the
dam failure, earthquake, and flood hazards.

For the other hazards, loss estimates were
generated by applying varying damage
percentages to an asset inventory extracted
from Hazus.

The methodology for evaluating potential
dollar losses is unchanged. Most-current
data was used in the analysis. Results
are presented in graphs rather than
tables to better display the relative
significance of the findings.
§201.6(c)(2)(ii)(C): [The plan should describe
vulnerability in terms of] providing a general
description of land uses and development
trends within the community so that mitigation
options can be considered in future land use
decisions.

There was a discussion on future development
trends as they pertain to each hazard of
concern. This discussion looked predominantly
at land use and the regulatory environment
that dictated that land use.

Discussion of future development and its
implications for hazard mitigation was
updated with most-current information.

MITIGATION STRATEGY
§201.6(c)(3): The plan shall include a
mitigation strategy that provides the
jurisdiction’s blueprint for reducing the potential
losses identified in the risk assessment, based
on existing authorities, policies, programs and
resources, and its ability to expand on and
improve these existing tools.

The plan contained a guiding principle, goals,
objectives, and actions. The actions were
jurisdiction-specific and strived to meet
multiple objectives. All objectives met multiple
goals and stood alone as components of the
plan. Each planning partner was asked to
complete a capability assessment that looked
at its regulatory, technical, and financial
capabilities.

The overall approach to establishing a
mitigation strategy based on goals,
objectives, and actions was unchanged.

Unlike the 2018 plan, which included
actions that apply to all planning
partners as well as actions specific to
each jurisdiction, the updated plan does
not include area-wide mitigation actions.

All actions are presented in the
jurisdiction-specific annexes included in
Volume 2.

Jurisdiction-specific capability
assessments were expanded to include
a discussion of each jurisdiction’s
capacity to expand or improve its
mitigation-related capabilities.
§201.6(c)(3)(i): [The hazard mitigation strategy
shall include a] description of mitigation goals
to reduce or avoid long-term vulnerabilities to
the identified hazards.

The Steering Committee developed a new
overall guiding principle for the plan, and
developed eight goals and 12 objectives, as
described in Chapter 17. The goals and
objectives were specifically for the 2018
hazard mitigation plan and were completely
new at that time. They were identified based
on the capabilities of the Planning Partnership.

The 2018 mission statement, goals, and
objectives were carried over to this plan
with minor wording revisions. One new
goal was added, calling for a new focus
on disaster resiliency for historically
underserved populations.
§201.6(c)(3)(ii): [The mitigation strategy shall
include a] section that identifies and analyzes
a comprehensive range of specific mitigation
actions and projects being considered to
reduce the effects of each hazard, with
particular emphasis on new and existing
buildings and infrastructure.

Volume I, Part 3 included a hazard mitigation
catalog that was developed through a
facilitated process. This catalog identified
actions that manipulate the hazard, reduce
exposure to the hazard, reduce vulnerability, or
increase mitigation capability. The catalog
further segregated actions by scale of
implementation. A table in the action plan
chapter analyzed each action by mitigation
type to illustrate the range of actions selected.

The catalogs were updated with the
newest best practices for each hazard
assessed.
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44 CFR Requirement 2018 Plan Updated Plan (2023)
§201.6(c)(3)(ii): [The mitigation strategy] must
also address the jurisdiction’s participation in
the National Flood Insurance Program, and
continued compliance with the program’s
requirements, as appropriate.

Dublin, Livermore and Pleasanton identified
actions stating their commitment to maintain
compliance and good standing under the
National Flood Insurance Program.

City planning partner mitigation actions
calling for ongoing NFIP commitment
have been retained in the updated plan.
§201.6(c)(3)(iii): [The mitigation strategy shall
describe] how the actions identified in Section
(c)(3)(ii) will be prioritized, implemented, and
administered by the local jurisdiction.

Prioritization shall include a special emphasis
on the extent to which benefits are maximized
according to a cost benefit review of the
proposed projects and their associated costs.

Each recommended actions was prioritized
using a qualitative methodology that looked at
the objectives the project will meet, the
timeline for completion, how the project will be
funded, the impact of the project, the benefits
of the project and the costs of the project. This
prioritization scheme was detailed in Chapter

19. Since this planning effort was the first for
all the Tri-Valley planning partners working
together on a plan, the prioritization concept
was entirely different from what was applied in
the ABAG planning effort. Since each planning
partner was asked to review all risks and prior
actions, any action that was carried over to this
plan from the prior plan had the opportunity to
have its priority reviewed and if necessary,
changed. Therefore, every risk and action in
this plan, whether new or carried over from the
prior plan, was prioritized as described in the
introduction section of Volume 2.

The prioritization and plan
implementation approaches from the
2018 plan have been carried over to this
update.

PLAN ADOPTION, IMPLEMENTATION, AND MAINTENANCE
§201.6(c)(4)(i): [The plan maintenance process
shall include a] section describing the method
and schedule of monitoring, evaluating, and
updating the mitigation plan within a five-year
cycle.

Volume I, Part 3 presented a plan
maintenance strategy that contains additional
detail to address deficiencies observed during
the 2010 update process. This update includes
a more defined role and vehicle for facilitating
the annual review of the plan.

The same general strategy for plan
maintenance is carried over from the
previous plan.
§201.6(c)(4)(ii): [The plan shall include a]
process by which local governments
incorporate the requirements of the mitigation
plan into other planning mechanisms such as
comprehensive or capital improvement plans,
when appropriate.

Volume I, Part 3 detailed recommendations for
incorporating the plan into other planning
mechanisms, such as:
• General plans
• Emergency response plans
• Capital improvement programs
• Municipal codes
Specific current and future plan and program
integration activities were detailed in each
participating jurisdiction’s annex in Volume 2.

The same general strategy for plan
integration with other planning
mechanisms is carried over from the
previous plan.
§201.6(c)(4)(iii): [The plan maintenance
process shall include a] discussion on how the
community will continue public participation in
the plan maintenance process.

Volume I, Part 3 detailed a comprehensive
strategy for continuing public involvement.

The same general strategy for ongoing
public involvement is carried over from
the previous plan.
§201.6(c)(5): [The local hazard mitigation plan
shall include] documentation that the plan has
been formally adopted by the governing body
of the jurisdiction requesting approval of the
plan (e.g., City Council, County Commission,
Tribal Council).

An appendix in Volume 1 contained the
resolutions of all planning partners that
adopted this plan.

Planning partners passed new adoption
resolutions for the update plan after
FEMA approval. The FEMA approval
letter and adoption resolutions are
included in a Volume 1 appendix.
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3. PLAN UPDATE APPROACH

3.1 FORMATION OF THE PLANNING TEAM
Project management for this update of the Tri-Valley hazard mitigation plan was the joint responsibility of staff members from the Cities of Dublin, Livermore, and Pleasanton, and the Dublin San Ramon Services District. A contract planning consultant (Tetra Tech, Inc.) was tasked with assisting in the development, update, and implementation of the plan. The Tetra Tech project manager assumed the role of the lead planner, reporting directly to the planning team. In addition to Tetra Tech project staff, the main planning team consisted of the following members:
• Susan Frost, Special Projects Manager, City of Livermore • Jake Potter, Associate Planner, City of Livermore
• Shweta Bonn, Senior Planner, Advanced Planning; City of Pleasanton • Diego Mora, Assistant Planner, City of Pleasanton
• John Stefanski, Assistant to the City Manager, City of Dublin • Aaron Johnson, GIS Analyst, Dublin San Ramon Services District

3.2 DEFINING STAKEHOLDERS
At the start of the planning process, the planning team identified a list of stakeholders to engage during the update of the Tri-Valley Hazard Mitigation Plan. “Stakeholder” was defined as any person or public or private entity that owns or operates facilities that would benefit from the mitigation actions of this plan, and/or has an authority or capability to support mitigation actions identified by this plan. Stakeholders were separated into two categories:
• Participatory Stakeholders—Stakeholders that actively participated in the planning process as planning partners or members of the Steering Committee.
• Coordinating Stakeholders—Stakeholders that were not able to commit to actively participating in the process but were kept apprised of plan development milestones or were able to provide data that was used in the plan development.

3.3 THE STEERING COMMITTEE
A Steering Committee provided guidance to the hazard mitigation plan effort and ensured that the document will be accepted by agencies and the public. For a project kickoff meeting on May 23, 2022, the planning team assembled a list of planning area candidates who could have recommendations for the plan or be impacted by its 125
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recommendations. The planning team requested these candidates’ participation in the planning process. The planning team confirmed a committee of 15 primary members and three alternates, as listed in Table 3-1.

Table 3-1. Steering Committee Members
Name Title Jurisdiction/Agency
Shweta Bonn Senior Planner City of Pleasanton
Lincoln Casimere Emergency Manager Alameda County Fire Department Herbert Cole Emergency Manager City of Livermore
Susan Frost a Special Projects Coordinator City of Livermore Cary Fukada b Citizen CERT
Matt Fuzie General Manager RPD City of Livermore
Tracy Hein Emergency Preparedness Manager Livermore-Pleasanton Fire Department Aaron Lacey Deputy Chief Livermore-Pleasanton Fire Department Christine Martin Assistant City Manager City of Livermore Franc Moufarrej Permit Center Manager City of Livermore Adam Nelkie Assistant Director of Engineering City of Pleasanton Aaron Johnson GIS Analyst Dublin San Ramon Services District Jerry Paulson Emergency Manager Lawrence Livermore National Laboratory Tricia Pontau Associate Planner City of Livermore
John Stefanski Assistant to the City Manager City of Dublin Alternate Members
Stephanie Egidio Management Analyst City of Livermore
Jake Potter Assistant Planner City of Livermore
a. Chair
b. Vice-Chair
Leadership roles and ground rules were established during the Steering Committee’s meeting on July 11, 2022.

The Steering Committee agreed to meet once a month as needed throughout the course of the plan’s development.

The planning team facilitated each Steering Committee meeting to address a set of objectives based on an established work plan. The Steering Committee met five times from July 2022 through April 2023. All Steering Committee meetings were open to the public and agendas and meeting notes were posted to the hazard mitigation plan website. Meeting minutes and the Steering Committee’s adopted ground rules are provided in Appendix F.

The Steering Committee included key planning partner staff, citizens, and other stakeholders from within the planning area. Members combined expertise in preventive measures, property protection, natural resource protection, emergency services, structural flood control projects, public safety, and public information. They applied their expertise on behalf of all planning partners participating in the plan process.

3.4 ESTABLISHMENT OF THE PLANNING PARTNERSHIP
Hazard mitigation planning enhances collaboration among diverse parties whose interests can be affected by hazard losses. In June 2022, the Cities of Dublin, Livermore, and Pleasanton identified eligible special districts within the planning area of the pending planning process and invited them to formally participate. All special districts were asked to identify planning points of contact to serve as planning partners and represent the interests of their district. The Dublin San Ramon Services District accepted the invitation to participate in the planning partnership.
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The planning partners covered under this plan are shown in Table 3-2. Together these jurisdictions make up the Planning Partnership for the hazard mitigation plan. While all participating jurisdictions authorized the Steering Committee to carry out certain activities on their behalf, all planning partners were invited to attend and participate in all aspects of the plan update process.

Table 3-2. Municipal and Special District Planning Partners Jurisdiction Point of Contact Title
Dublin John Stefanski Assistant to the City Manager
Livermore Susan Frost
Jake Potter
Special Projects Coordinator
Associate Planner
Pleasanton Shweta Bonn Senior Planner
Diego Mora Assistant Planner
Dublin San Ramon Services District Aaron Johnson Associate Engineer Jason Ching Senior Engineer

3.5 DEFINING THE PLANNING AREA
The planning area was defined to consist of the jurisdictional area of the Cities of Dublin, Livermore, and Pleasanton within Alameda County as well as the service area for the Dublin San Ramon Services District that extends into Contra Costa County. The planning area is surrounded by unincorporated Alameda County. All partners to this plan have jurisdictional authority within this planning area. A map showing the geographic boundary of the defined planning area for this plan update is provided in Chapter 4, along with a description of planning area characteristics.

For the risk assessment in this hazard mitigation plan, risks to population and the general building stock were evaluated only within the city limits of the three municipal planning partners. Those risks are not relevant to the Dublin San Ramon Services District, which does not have the same regulatory authorities as cities in terms of mitigating risks to people and development.

3.6 COORDINATION WITH STAKEHOLDERS AND AGENCIES
Opportunities for involvement in the planning process must be provided to neighboring communities, local and regional agencies involved in hazard mitigation, agencies with authority to regulate development, businesses, academia, and other private and nonprofit interests (44 CFR, Section 201.6(b)(2)). The planning team accomplished this task as follows:
• Steering Committee Involvement—Agency representatives were invited to participate on the Steering Committee and comment on the draft plan.
• Agency Notification—The following agencies were invited to participate in the plan development process from the beginning and were kept apprised of plan development milestones. Many of the organizations listed assist at-risk and socially vulnerable populations, including those with developmental disabilities, those with access and functional needs, at-risk youth and seniors, those with limited access to childcare, and those who have suffered through or are currently experiencing homelessness. These agencies were advised of the planning efforts and invited to comment on the draft plan. ➢ Alameda County Fire Department, Emergency Management Division ➢ Alameda County Office of Emergency Services
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➢ Alameda County Voluntary Organizations Active in Disaster (VOAD)—VOAD is a humanitarian association of independent voluntary organizations active in emergency disaster relief with a mission to provide efficient services to all disaster victims and eliminate the duplications of services (ALCOVOAD n.d.).
➢ Alameda County Emergency Managers Association
➢ American Red Cross Bay Area Chapter (ARC)—ARC works in communities to provide relief following emergencies and disasters
➢ Association of Bay Area Governments, Resilience Program Coordinator ➢ Bay Area Rapid Transit
➢ California Department of Water Resources, National Flood Insurance Program Coordinator ➢ California Governor’s Office of Emergency Services (Cal OES) ➢ Contra Costa County Office of Emergency Services
➢ East Bay Parks and Recreation District
➢ FEMA Region 9, Lead Community Planner
➢ Lawrence Livermore National Laboratory
➢ Livermore Area Recreation & Park District (LARPD) (includes senior groups) ➢ Los Positas College (academia)
➢ East Bay Innovations (access and functional needs)
➢ Livermore-Pleasanton Fire Department
➢ Pleasanton Chamber of Commerce
➢ San Ramon Valley Fire District
➢ Stanford Health Care – Valley Care (medical care)
➢ Zone 7 Water Agency
➢ Livermore’s Multi Services Center (unhoused, non-English speakers) ➢ Quest Science Center (youth and disadvantaged youth)
These agencies received meeting announcements, meeting agendas, and meeting minutes by e-mail throughout the plan development process. They supported the effort by attending meetings or providing feedback on issues.
• Pre-Adoption Review— All the agencies listed above were provided an opportunity to review and comment on this plan, primarily through the hazard mitigation plan website (see Section 3.8.1). All were sent an e-mail message informing them that draft portions of the plan were available for review.

Special involvement in and assistance with the planning process was provided by the following federal and state agencies:
• FEMA Region 9 provided updated planning guidance, provided summary and detailed data for the planning area from the National Flood Insurance Program (NFIP) (including repetitive loss information), and conducted plan review.
• The U.S. Geological Survey (USGS) provided earthquake event mapping to support the earthquake risk assessment.
• Cal OES facilitated FEMA review, provided updated planning guidance, and reviewed the draft and final versions of the plan prior to FEMA review.
• The California Department of Forestry and Fire Protection (CAL FIRE) provided fire severity mapping to support the wildfire risk assessment.
• The California Department of Water Resources provided information on NFIP compliance for local cities. 128

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The following sections identify agencies and organizations maintaining close partnerships with the cities of Dublin, Livermore, and Pleasanton, as well as the Dublin San Ramon Services District to provide opportunities for members of underserved and socially vulnerable populations to participate in the planning process and comment during its progress and on the draft plan.

3.6.1 City of Dublin
The City of Dublin provides targeted outreach to its senior population, which has been identified by the city as an at-risk or socially vulnerable population, through the following programs:
• Meals on Wheels—Dublin seniors aged 60 and older who are home-bound and unable to cook have access to nutritious meals at little to no cost.
• Diabetes Support Group—The Alameda County Public Health Department offers a course on how to manage diabetes and monitor blood sugar as a free local service. • Senior Health Screening and Foot Care—Free senior health screenings that include blood tests, diabetes tests, health education services and many other resources are offered quarterly by the Senior Support Program of the Tri-Valley for Alameda County residents. • Computer and Wi-Fi Access—Unlimited access to the internet through desktop computers and wi-fi is available at no cost through the Dublin Senior Center for seniors who do not have access to reliable internet connection.
• Alameda County VOAD—VOAD is a humanitarian association of independent voluntary organizations active in emergency disaster relief, with a mission to provide efficient services to all disaster victims and eliminate the duplications of services (ALCOVOAD n.d.).

3.6.2 City of Livermore
The City of Livermore maintains an ongoing partnership with the following agencies to provide up-to-date information to at-risk communities:
• Livermore Area Recreation & Park District (LARPD)—Provides services and programs to adults and seniors aged 50 and older, such as a Senior Lunch Program (60+) and 50+ Service and Support Groups.

LARPD’s mission is to improve the quality of life for Livermore’s older adults and their families by educating and advocating for health and social services while providing recreation, socialization, and meaningful volunteer opportunities to encourage active and healthy lives (LARPD n.d.). • East Bay Innovations (EBI)—EBI offers services supporting over 500 individuals with disabilities to live as independently as possible in their own homes, be successfully employed, and feel a sense of membership in their community (East Bay Innovations n.d.). • Abode Services—Abode’s mission is to end homelessness by assisting low-income, unhoused people, including those with special needs, to secure stable, supportive housing, and to be advocates for the removal of the causes of homelessness.
• Alameda County VOAD—VOAD is a humanitarian association of independent voluntary organizations active in emergency disaster relief with a mission to provide efficient services to all disaster victims and eliminate the duplications of services (ALCOVOAD n.d.).

The City has conducted the following activities to supplement outreach to socially vulnerable populations:
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• August 26, 2023—The City of Livermore attended the “Weather Wonders” youth outreach event hosted by the Quest Science Center to showcase this Plan.
• The City of Livermore has distributed a copy of this Plan to Livermore’s Multi Service Center, which provides services to those experiencing homelessness, non-English speakers, and other at-risk and socially vulnerable groups.

3.6.3 City of Pleasanton
The City of Pleasanton hosts a number of ongoing programs for senior citizens, who have been identified by the city as an at-risk or socially vulnerable population. The following are examples of these programs:
• Pleasanton Rides—Provides safe, reliable, and affordable transportation for seniors aged 70 and older. • Open Heart Kitchen—Provides free lunch for seniors aged 60 and older. • Meals on Wheels—Provides meals for seniors aged 60 and older with annual registration. • Alameda County VOAD—VOAD is a humanitarian association of independent voluntary organizations active in emergency disaster relief with a mission to provide efficient services to all disaster victims and eliminate the duplications of services (ALCOVOAD n.d.).

In addition to these programs, a number of financial assistance programs are available for the senior population, including emergency loans and grants for seniors experiencing extreme financial hardship (Wiesner Senior Fund), a 20 percent discount on water bills, and a fee assistance program for senior recreation activities.

3.6.4 Dublin San Ramon Services District
Since the DSRSD covers most of the City of Dublin, DSRSD collaborates and works closely with the City in its outreach efforts to businesses, community organizations, and at-risk and socially vulnerable communities such as seniors and older adults in the Tri-Valley planning area.

3.7 REVIEW OF EXISTING PROGRAMS
Hazard mitigation planning must include review and incorporation, if appropriate, of existing plans, studies, reports and technical information (44 CFR, Section 201.6(b)(3)). In addition, the following programs can affect mitigation within the planning area:
• California Fire Code
• 2022 California Building Code
• California State Hazard Mitigation Forum
• Five-year and biennial capital improvement programs
• Local emergency operations plans
• Local general plans, including housing and safety elements • Local strategic plans
• Local zoning ordinances
• Climate action plans.
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An assessment of all planning partners’ planning and regulatory; permitting; fiscal; administrative and technical; and education and outreach capabilities to implement hazard mitigation actions is presented in the jurisdictionspecific annexes in Volume 2. Chapter 1 provides a review of laws and ordinances in effect within the planning area that can affect hazard mitigation actions.

3.8 PUBLIC INVOLVEMENT
Broad public participation in the planning process helps ensure that diverse points of view about the planning area’s needs are considered and addressed. The public must have opportunities to comment on disaster mitigation plans during the drafting stages and prior to plan approval (44 CFR, Section 201.6(b)(1)). This section details the outreach to, and involvement of, the many agencies, departments, organizations, non-profit organizations, districts, authorities and other entities that have a stake in managing hazard risk and mitigation, commonly referred to as stakeholders.

3.8.1 Strategy
The strategy for involving the public in this plan emphasized the following elements:
• Include members of the public on the Steering Committee. • Engage the public and organizations that are listed in Section 3.6 by providing updates and an opportunity to comment on a draft of the plan.
• Use a survey to determine if the public’s perception of risk and support of hazard mitigation has changed since the initial planning process.
• Attempt to reach as many planning area residents as possible using multiple media. • Identify and involve planning area stakeholders.
• Develop a StoryMap of the planning area for public access (https://experience.arcgis.com/experience/809c8425c55a4e31b35884794aaa1060/?draft=true). The map provides information on hazards based on specific locations. It also has the ability to send an email requesting information.

Diligent efforts were made to ensure broad regional, county, and local representation in this planning process.

Stakeholder outreach was performed early and throughout the planning process. In addition to mass media notification efforts, identified stakeholders were invited via email and social media posts to attend meetings and provide input on draft documents. Information and input provided by these stakeholders has been included throughout this plan where appropriate, and all were given an opportunity to comment on the draft plan.

Outreach efforts reflecting a whole community approach were conducted collaboratively across all four jurisdictions to ensure members of local businesses, academia, private organizations, and marginalized communities were provided the opportunity to have a voice in the planning process. The following private organizations were partnered with to drive public outreach efforts:
• Dublin Chamber of Commerce
• Livermore Valley Chamber of Commerce
• Pleasanton Chamber of Commerce
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An emphasis was placed on including representatives from marginalized, at-risk, and socially vulnerable communities in the planning process through the following methods by each jurisdiction:
• City of Dublin—Due to the City of Dublin’s regular partnership and collaboration with their senior community, seniors in Dublin were the primary focus of outreach activities at the Dublin Senior Center. • City of Livermore—The planning team collaborated with the Livermore Multi Service Center to involve at-risk seniors and unsheltered people in the planning process through the distribution of this Plan to the Center.
• City of Pleasanton—Outreach was conducted through social media outlets, the Pleasanton Community Page, and the Pleasanton city website to promote involvement in the planning process, especially for the local senior community.
• DSRSD—The District collaborates with the City of Dublin on its outreach and public involvement strategies as explained in Section 3.6.

The sections below describe Steering Committee and planning team efforts toward public outreach throughout the development and review of the hazard mitigation plan.

Website
At the beginning of the plan development process, a planning partnership website was created on the City of Livermore’s Planning Department web page to keep the public posted on plan development milestones and to solicit relevant input (see Figure 3-1).

The site’s address (https://www.livermoreca.gov/departments/community-development/planning/hazardmitigation) was publicized in all press releases, mailings, and public meetings. Information on the plan development process, the Steering Committee, the survey and phased drafts of the plan was made available to the public on the site throughout the process. The planning partners intend to keep a website active after the plan’s completion to keep the public informed about successful mitigation projects and future plan updates.

Hazard Mitigation Survey
A hazard mitigation plan survey (see Figure 3-2) was developed for this planning process.

The survey was used to gauge household preparedness for natural hazards and the level of knowledge of tools and techniques that assist in reducing risk and loss from natural hazards. This survey was designed to help identify areas vulnerable to one or more natural hazards. The answers to its questions helped guide the Steering Committee in selecting mitigation strategies.

The survey was made available on the hazard mitigation plan website and was distributed to community members in the planning area as follows:
• Via social media outlets, including Facebook, Twitter and Nextdoor • At virtual public meetings via web link and QR code
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Figure 3-1. Hazard Mitigation Plan Web Site Homepage
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Figure 3-2. Hazard Mitigation Survey
StoryMap
An online StoryMap was created to communicate the variety and severity of hazards in the Tri-Valley planning area (see Figure 3-3). During the update process, the StoryMap was released to the public and promoted through social media, the project website, and during Steering Committee meetings, which were open to the public. It includes risk assessment results for hazards of concern, an interactive hazard mapping tool, and a report function to produce hazard exposure summaries for a specified address or area. 134

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Figure 3-3. Tri-Valley StoryMap
Public Comment
A 14-day public comment period, from May 8 to 22, 2023, provided the public an opportunity to comment on the draft plan update prior to its submittal to Cal OES. The principal mechanism for public comment on the draft plan was a virtual public comment form. Additionally, a public meeting held in conjunction with a Steering Committee meeting on May 15, 2023, allowed an opportunity to provide comment on the draft plan update. At the public meeting, a 30-minute presentation was given, followed by a period for questions and answers by those in attendance. Comments received on the draft plan are available upon request.

The draft Hazard Mitigation Plan was widely distributed for comment for a 14-day public comment period, including agencies identified in Section 3.6. Outreach efforts, including those to socially vulnerable communities, are described in Section 3.6. During that time, none of the planning partners received any comments. Because there were no comments submitted, no associated demographic data was available.

Social Media
The planning partners posted announcements about the plan update on their social media platforms including Facebook, Twitter, Instagram, and Nextdoor (Figure 3-4).

Print, Email, and Other Outreach
Planning partners distributed press releases and performed email outreach over the course of the plan’s development as key milestones were achieved. Press releases and resulting press coverage included the following:
• September 22, 2022—Dublin Patch: Announcement of commencement of the planning project and invitation to the public to take the hazard awareness survey. • September 2022—The plan update was promoted at the Livermore/Pleasanton CERT meeting and a subsequent flyer was emailed to all CERT members.
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Figure 3-4. Social Media Public Outreach

3.8.2 Public Involvement Results
Survey Response
Detailed analysis of the survey findings is presented in Appendix A; a summary is as follows:
• 585 surveys were completed.
• Surveys were received from residents of each participating planning partner. • Survey respondents ranked drought as the hazard of greatest concern, followed by wildfire and earthquake.
• More than 80 percent of respondents reported having experienced a drought, over 69 percent reported having experienced an earthquake, and nearly 55 percent reported having experienced a severe weather event.
• Most respondents (78.38 percent) felt that they were somewhat prepared to deal with a hazard event and more than 60 percent keep an emergency kit with spare food and water. • Nearly 66 percent of respondents would consider retrofitting their home to withstand hazard events if they received an insurance discount, while about 50 percent would do so if they received free government technical assistance. Another 40 percent would do retrofits if they had a building permit fee waiver.

Survey results were provided to the Steering Committee for use in support of confirming the guiding principle, goals, objectives and county-wide actions for this plan update. Additionally, the survey results were included in the toolkit provided to each planning partner through the jurisdictional annex process described in Volume 2.

Each planning partner was able to use the survey results to help identify actions as follows:
• Gauge the public’s perception of risk and identify what citizens are concerned about. • Identify the best ways to communicate with the public. 136

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• Determine the level of public support for different mitigation strategies. • Understand the public’s willingness to invest in hazard mitigation.

3.9 PLAN DEVELOPMENT CHRONOLOGY/MILESTONES
A summary of Planning Partnership activities, including Steering Committee meetings held during development of this hazard mitigation plan, is included in Table 3-3. 137
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Table 3-3. Plan Development Chronology/Milestones
Date Event Description Attendance
2022
3/9 Support Contractor Secured Contract executed with Tetra Tech, Inc. to facilitate the plan update process N/A 5/23 Planning Team Meeting #1 Planning Process 10
6/6 Planning Team Meeting #2 Planning Process 10
6/10 Jurisdictional Annex Process Phase 1 Planning partners begin the jurisdiction annex update process with the team, profile, trends, and previous plan status updates N/A
6/20 Planning Team Meeting #3 Planning Process 10
7/5 Planning Team Meeting #4 Planning Process 10
7/8 Jurisdictional Annex Process Phase 2 Planning partners continue the jurisdictional annex update process with the capability assessment, integration review, and information sources updates N/A
7/11 Steering Committee Meeting #1 • Project overview
• Steering Committee’s role
• Hazards of concern
• Review of mission statement, goals and objectives
• Public involvement strategy
21 7/18 Planning Team Meeting #5 Planning Process 7
8/1 Planning Team Meeting #6 Planning Process 6
8/1 Steering Committee Meeting #2 • Approve ground rules • Approve mission statement, goals and objectives
• Approve hazard of concern
• Approve community lifelines
• Public involvement strategy
16 8/14 Public Outreach Hazard awareness survey open and promotion started N/A 8/29 Planning Team Meeting #7 Planning Process 9
9/26 Planning Team Meeting #8 Planning Process 9
10/3 Steering Committee Meeting #3 • Social vulnerability discussion • Discuss hazards of concern and risk assessment
• Outreach and engagement progress
15 10/24 Planning Team Meeting #9 Planning Process 7
11/8 Jurisdictional Annex Workshop Workshop for planning partners to assist in development of Phase 3 of the jurisdictional annex process
22 11/21 Planning Team Meeting #10 Planning Process 7
12/5 Steering Committee Meeting #4 • Accepted social vulnerability definition • Outreach and engagement update
12 2023
1/9 Planning Team Meeting #11 Planning Process 10
1/30 Planning Team Meeting #12 Planning Process 9
1/31 Public Outreach Hazard awareness survey closed 585 2/27 Planning Team Meeting #13 Planning Process 7
3/13 Planning Team Meeting #14 Planning Process 9
3/27 Planning Team Meeting #15 Planning Process 5
5/8 Public Comment Period Begins Public involvement strategy N/A 5/15 Steering Committee Meeting #5
and Public Meeting
• Draft plan overview
• Public comment period
16 5/22 Public Comment Period ends Public involvement strategy N/A 6/15 Plan submittal Pre-adoption review draft of the plan submitted to Cal OES. N/A TBD Approval Final plan approval issued by FEMA Region 9 N/A 138
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4. COMMUNITY PROFILE

4.1 GEOGRAPHIC OVERVIEW
The Tri-Valley planning area is in north-central Alameda County in the San Francisco Bay area, east of San Francisco and north of San Jose. The cities of Dublin, Livermore and Pleasanton are located along Interstate 580, which runs east-west through the county. The City of Dublin is north of the intersection of Interstates 580 and 680 and is generally bounded by the City of San Ramon to the north, Castro Valley to the west, the City of Pleasanton to the south, and the City of Livermore to the east. The City of Livermore is north and south of Interstate 580. The Livermore Valley is edged to the north, south, and east by rolling hills, with the cities of Pleasanton and Dublin to the west. The City of Pleasanton extends south of Interstate 580 along Interstate 680, bounded by the City of Dublin on the north, the City of Livermore to the east, the Sunol Valley to the south, and the steep, rugged Pleasanton and main ridges on the west. Figure 4-1 shows the 66.2-square-mile planning area.

4.2 HISTORICAL OVERVIEW
For thousands of years until the arrival of Spanish settlers in the late 1700s, the Ohlone people, also referred to as Costanoans (the Spanish word for “coast”), lived in and around the Bay Area. Living in small villages, they survived on the abundance of natural resources, including acorns from oak trees and shellfish in the bay. Mission San Jose was founded on June 11, 1797, by Father Fermín Francisco de Lasuén. It was the 14th of the 21 Spanish missions in what is now the western United States. The missionaries required the Indians to move to the mission, and this disruption, as well as new diseases the Spanish brought, destroyed the Indian way of life even before the influx of gold seekers in the mid-1800s.

The Amador-Livermore Valley was first sighted by a Spanish solder in 1772 while on an expedition searching for new mission sites. After 1822, Mexico succeeded Spain in jurisdiction over Alta California. Beginning in 1839, the former mission lands were secularized and broken up into large ranchos as the result of grants to citizens by Mexico. It was a half-century after the initial discovery that Jose Amador, in 1826, brought the first settlement to the valley and Spanish families were awarded large tracts of land.

California became part of the United States after the Mexican War of 1846–1847. The territory was formally ceded in the treaty of Guadalupe Hidalgo in 1848 and was admitted as a state in 1850. Pressure from the United States was a major factor leading to the disintegration of Mexican control in California. The first American settler in the tri-valley area arrived in 1850 and settlement continued. The area was on one of the main routes to the gold fields and became a mercantile stopover for miners on their way to those fields.

Ranchers and thoroughbred horse breeders, also came to the area, attracted to the favorable climate and abundance of water, and were followed by dairy farms, hop fields, and vineyards. The Central Pacific Railroad was completed in 1869, resulting in the establishment of more towns. 139

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In 1925, the section of the Lincoln Highway through the area (by 1874 known as Dublin Road) was incorporated into the U.S. Highway system as U.S. Highway 50. In 1928, it was also designated State Route 84. By 1953, U.S.

Highway 50 had become a divided four-lane road; Interstate 680 was completed in 1967. By 1973, U.S. Highway 50 had become Interstate 580. Prior to the 1950s, small agricultural towns history and economy were integrated with those of the agricultural areas around them. Since the 1950s, urbanization of the area has grown across former agricultural land, and urban development now dominates the area (Corbett 2005).

Over the last two decades, the Tri-Valley has experienced an influx of people and jobs, growing at a faster rate than the Bay Area as a whole. In 2011, the West Dublin/Pleasanton BART (Bay Area Rapid Transit) station opened, providing another commute option between San Francisco and the Tri-Valley (Bay Area Council Economic Institute n.d.).

4.3 PHYSICAL SETTING

4.3.1 Topography and Geology
The planning area is in the east-central part of the California Coast Range Province that is characterized by elongated ranges and narrow valleys parallel to the coast. It lies in a depression within the Diablo Range where there are three valleys: Amador Valley, Livermore Valley, and San Ramon Valley. The Livermore and Amador Valleys, which are adjacent in an east-west orientation, make up the major part of the basin. San Ramon is a smaller valley that trends northwest from the northwest edge of Amador Valley. Elevations in the planning area range from approximately 300 feet above sea level at the drainage exit of Amador Valley southwest of Pleasanton, to approximately 700 feet above sea level along Livermore Valley’s eastern margin. The mean elevation above sea level is 486 feet in the City of Livermore and 354 feet in the City of Dublin. North and east of the Tri-Valley area, the Diablo Range rises to elevations between approximately 1,000 and 2,000 feet above sea level, with Mount Diablo reaching an elevation of 3,849 feet above sea level.

Geologic conditions are controlled by the planning area’s location along the complex boundary between the North American and Pacific Plates and the interaction of these two plates. The Pacific Plate moves northwestward relative to the North American Plate at a rate of about 5 centimeters per year. Much of this relative movement at the latitude of the San Francisco Bay Area is accommodated primarily by strike-slip motion along a number of major faults, including the San Gregorio, San Andreas, Hayward, Calaveras, and Greenville faults. Countless other faults in the region accommodate relative motion between major faults and relieve compression stress along the plate boundary.

4.3.2 Hydrology
The Tri-Valley area consists of sub-watersheds of the Alameda Creek Watershed. Arroyo Las Positas, Arroyo Seco, and Arroyo Mocho drain the northeastern and southeastern hills, and Arroyo del Valle drains the southern hills. These drainages converge and flow through the central Tri-Valley area, collecting the flow of Cayetano, Collier, Cottonwood, Tassajara, and Alamo Creeks from the northern hills. These streams join San Ramon Creek, which flows south through the San Ramon Valley and exits the basin along Arroyo de la Laguna. Figure 4-2 shows the entire Alameda Creek Watershed and major water bodies around the Tri-Valley area. 141
Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements 4-4
Source: (Alameda Creek Alliance n.d.)
Figure 4-2. Watersheds and Water Bodies in the Planning Area

4.3.3 Climate
The climate of the planning area is moderated by its proximity to the San Francisco Bay, with average annual temperatures ranging from 45.7 degrees Fahrenheit (ºF) to 73.6 ºF. Climate records from the NOAA National Weather Service Forecast Office describe the region’s climate as Mediterranean type. This classification is characterized by sharply contrasting wet and dry seasons, with the wet season from November through March bringing more than 80 percent of the total annual precipitation. Rainfall is sparse from May through September.

Mean precipitation in June, July and August in Livermore normally totals only 0.11 inches. Wet seasons are cool but mild, with mean monthly temperatures of 48.3 ºF in January to 53.9 °F in March. Dry season weather is very consistent, with warm sunny days and average temperatures reaching 72.8 °F in June, July, August, and September.

Average temperature and precipitation across the planning area by month are shown in Figure 4-3. The total annual average precipitation is 13.38 inches. Annual average maximum and minimum temperatures are 48.3 ºF and 72.8 ºF, respectively.

In the past several years California experienced significant drought. However, in the winter of 2022 – 2023 much of the state was beset by multiple atmospheric rivers bringing substantial precipitation – rain and snow – that contributed to flooding and landslide issues in various parts of the state. 142

4. Community Profile
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Source: (National Weather Service 2023)
Figure 4-3. Normal Precipitation and Temperatures in Planning Area, 2000-2023

4.4 DEVELOPMENT PROFILE

4.4.1 Land Use
Dublin
The City of Dublin, located north of Interstate 580, covers 15.51 square miles, or 9,923.6 acres. As of 2017, the city accommodates 20,931 housing units. The City has defined the following planning areas:
• The Primary Planning Area consists of the original city boundaries and annexations completed through 1991. It covers roughly 3,100 acres.
• The Eastern Extended Planning Area is east of the Primary Planning Area and south and east of the U.S.

Army’s Parks Reserve Forces Training Area (Camp Parks). It covers roughly 4,300 acres. • The Western Extended Planning Areas is west of the Primary Planning Area. It consists of 3,200 acres, mostly outside Dublin’s urban limit line, which encompasses the city areas with access to city utilities and road maintenance services.
• The Dublin Crossing Planning Area, a portion of Camp Parks, covers 189 acres in the center of the city where existing buildings are scheduled for demolition to be replaced with a residential mixed-use project.

The city’s land use includes a mixture of public open space, commercial/industrial, and residential. Development guidelines for the Eastern Extended Planning Area consider visually sensitive ridge lands and biologically sensitive habitat areas to preserve key elements of the area’s physical character. A development elevation cap keeps growth within the 770-foot elevation that is the highest serviceable elevation for water service.

Development is allowed in only a small portion of the Western Extended Planning Area; that area is out of view from the major ridgelines so it can be developed without disrupting scenic values (City of Dublin 2022).

2.38 2.36 1.86 1.08 0.39 0.1 0 0.01 0.09 0.95 1.46 3.22 20 23
28 31
36 43
48 48
42 34
26 23
76 80
86 94
104
109 113
108
113
103
85 73
0 1
2 3
4 0
25 50
75 100
125
Average Precipitation (inches)
Average Temperature (ºF)
Precipitation (inches) Minimum Temperature (ºF) Maximum Temperature (ºF) 143
Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements 4-6
Livermore
The City of Livermore, on the eastern side of the Tri-Valley planning area, covers approximately 24 square miles.

As of 2019, the city accommodates 32,883 housing units. Single-family residential development is the predominant land use within the city limits, with residential subdivisions scattered throughout the city. Other land uses are agriculture, open space and parks, industry, retail and office space, and community facilities. The city has a defined urban growth boundary to protect agricultural uses and natural resources outside the city from future urban development (City of Livermore 2022).

Pleasanton
The City of Pleasanton covers approximately 24 square miles, with additional areas designated for future land use. A 42-square-mile sphere-of-influence area represents the probable ultimate physical boundary and service area of the city. If all residential land shown on the General Plan Map is built out, Pleasanton will contain approximately 29,000 housing units by 2025. City land use policy allows for well-planned neighborhoods and a separation between residential and non-residential uses. As of 2019, there were 77 residential neighborhoods and 17 commercial, office, and industrial development sub-areas. The City’s growth management ordinance regulates the location and rate of new residential growth (City of Pleasanton 2019).

Dublin San Ramon Services District
The DSRSD was formed in 1953 as the Parks Community Services District. Its name transformed over the years.

Today, the DSRSD is a water retailer for the City of Dublin area and wastewater collection and treatment for Dublin and San Ramon. Under contract, it also treats wastewater collected by the City of Pleasanton. From its origins, the District has grown in proportion to the growth in population and businesses in the Dublin area (DSRSD 2023).

4.4.2 Building Count, Occupancy Class and Estimated Replacement Value Table 4-1 presents planning area building counts by building occupancy class. Table 4-2 summarizes estimated replacement value for building structures and contents. For the DSRSD, buildings listed include only critical facilities owned by the district.

Table 4-1. Planning Area Building Counts by Occupancy Class Number of Buildings
Agricultural Commercial Education Government Industrial Religion Residential Total Dublin 15 453 182 247 42 20 14,550 15,509
Livermore 1 1,189 496 518 381 95 28,213 30,893
Pleasanton 0 1,414 246 20 154 40 21,779 23,653
DSRSD 0 0 0 2 0 0 0 2
Total 16 3,056 924 787 577 155 64,542 70,057
Based on GIS data provided to Tetra Tech in May 2022 by the Cities of Dublin, Livermore, and Pleasanton and DSRSD 144

4. Community Profile
4-7
Table 4-2. Planning Area Replacement Value
Estimated Replacement Value
Structure Contents Total
Dublin $12,356,612,767 $8,098,062,522 $20,454,675,289
Livermore $16,693,865,603 $13,105,030,879 $29,798,896,482 Pleasanton $16,903,633,696 $12,445,602,543 $29,349,236,239 DSRSD $14,629,000 $202,944,505 $16,129,000
Total $45,968,741,066 $33,851,640,449 $79,618,937,010

4.4.3 Community Lifelines
The Community Lifeline Concept
Community lifelines, as defined by FEMA, are the most fundamental functions of a community. Lifelines are all the services, capabilities, and physical assets that are used day-to-day to support a community’s ongoing needs.

When stabilized and working properly, community lifelines enable all other aspects of society to function. The following are the seven basic community lifelines (in alphabetical order) and multiple components of each, as defined by FEMA (FEMA 2019):
• Communications
➢ Infrastructure
➢ Responder communications
➢ Alerts, warnings, and messages
➢ Finance
➢ 911 and dispatch
• Energy
➢ Power grid
➢ Fuel
• Food, water, shelter
➢ Food
➢ Water
➢ Shelter
➢ Agriculture
• Hazardous material
➢ Facilities
➢ Hazmat, pollutants, contaminants
• Health and medical
➢ Medical care
➢ Public health
➢ Patient movement
➢ Medical supply chain
➢ Fatality management
• Safety and security
➢ Law enforcement/security
➢ Fire service
➢ Search and rescue
➢ Government service
➢ Community safety
• Transportation
➢ Highway/roadway/motor vehicle
➢ Mass transit
➢ Railway
➢ Aviation
➢ Maritime
FEMA further defines subcomponents for each of the above components—nearly 100 altogether. These subcomponents include physical facilities as well as public and private services, capabilities, activities, and systems. The essential subcomponents that make up community lifelines range from police stations to farm animals, from public records to the food supply chain, and from medical treatment to banking services. 145
Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements 4-8
Lifelines Identified for This Plan’s Risk Assessment
It is an essential element of hazard mitigation planning to identify the community lifelines whose function can be negatively impacted by hazard events and to develop mitigation actions that will minimize the potential for such impacts. For this hazard mitigation plan, the assessment of community lifelines focuses on physical assets—the critical facilities and infrastructure that can be geographically located within mapped hazard areas and for which quantitative estimates can be made of current value and potential loss. These are referred to as critical facilities throughout the plan. Across the planning area, 1,161 such facilities were identified by each of the planning partners for analysis, geographically distributed as follows:
• Dublin—101 facilities
• Livermore—507 facilities
• Pleasanton—502 facilities
• Dublin San Ramon Services District—51 facilities
Figure 4-4 and Figure 4-5 show the general locations of these critical facilities in the planning area. Figure 4-6 summarizes counts of identified physical community lifeline assets in the planning area by category, based on the best data available at the time of this plan. This information is subject to change as new information about such structures becomes available during the performance period for this plan.

4.4.4 Development Trends
The planning area municipal partners have adopted general and economic development strategic plans to guide future growth, both local and area-wide, and ensure the orderly development of the communities. Development forecasts and development trends assist in providing a long-term vision for the planning area’s future and a strategy for achieving the desired vision. This plan aligns with these development programs and provides vital information on the risk associated with natural hazards in the planning area to support wise land use in the future.

Tracking building permit volume can be a way of looking at the potential increase in exposure within the planning area. Whether a permit is issued for new construction or improvement to existing construction, the permit volume can be associated with an increase in exposed value. The number of residential building permits reported in the planning area has fluctuated significantly from a low of 227 permits in 2007 to a high of 965 permits in 2014. The number of permits stayed steady through 2018, then consistently dropped through 2021. In 2021, the City of Dublin issued residential building permits for 131 buildings, which was significantly higher than the City of Livermore, with 89, and the City of Pleasanton, with 25.

Figure 4-7 shows the trends in residential development projects in the planning area since 2005. Additional cityspecific development trend information is provided in the city-specific annexes in Volume 2 of this plan. 146
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CO NTRA COSTA COU NTY

CITY OF

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LIVERMORE
FIGURE 4-4. CRITICAL
FACILITIES (MAP 1 OF 2)
0 2 4
Miles
O Data Sources: City of Dublin, City of Livermore,
City of Pleasanton, Dublin San Ramon Services District, Alameda County, ESRI
Map created for the 2023 Tri-Valley Local Hazard Mitigation Plan Rail
Interstate
Expressway
Major Road

CITY OF
DUBLIN
County Boundary
!. Health and Medical
!. Food, Water, Shelter
!. Safety and Security
City Boundary
Dublin San Ramon
Services District
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CO NTRA COSTA COU NTY

CITY OF

PLEASANTON

CITY OF

LIVERMORE
FIGURE 4-5.CRITICAL
FACILITIES (MAP 2 OF 2)
0 2 4
Miles
O Data Sources: City of Dublin, City of Livermore,
City of Pleasanton, Dublin San Ramon Services District, Alameda County, ESRI
Map created for the 2023 Tri-Valley Local Hazard Mitigation Plan Rail
Interstate
Expressway
Major Road

CITY OF
DUBLIN
County Boundary
!. Communications
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!. Hazardous
Materials
City
Dublin San Ramon
Services District
148

4. Community Profile
4-11
Figure 4-6. Planning Area Critical Facilities by Jurisdiction and Category Source: City-Data.com 2017; City of Dublin 2022; City of Livermore 2022; City of Pleasanton 2022 DSRSD does not have permit authority
Figure 4-7. Residential Building Permit Trends, 2005 to 2021 0 0
0 6 13 46 36
7 6
1 367
26 48 52 14 3
87 268
31 39 60 0
0 51
0 0
0 0
Total
21 Total
9 Total
139
Total
641
Total
70 Total
133
Total
148
0 100
200
300
400
500
600
700
Communications Energy Food, Water,
Shelter
Hazardous
Material
Health & Medical Safety & Security Transportation
Number of Facilities
Dublin San Ramon Services District
Pleasanton
Livermore
Dublin
0 100
200
300
400
500
600
700
800
900
1,000
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Number of Residential Building Permits
Dublin
Livermore
Pleasanton
Planning Area Total
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The municipal partners will incorporate this hazard mitigation plan in their general plans by reference. This will ensure that future development trends can be established with the benefits of the information on risk and vulnerability to natural hazards identified in this plan. The planning partners intend to pursue the following:
• Discourage development within vulnerable areas, areas with the potential for high population density, and Special Flood Hazard Areas.
• Encourage higher regulatory standards at the local level.

Future development is expected to focus on infill as identified through current land use practices. Dublin, Livermore and Pleasanton are largely built out, and with sustainability practices and urban growth boundaries in place, there is little opportunity for new growth.

4.5 DEMOGRAPHICS

4.5.1 Population Characteristics
Knowledge of the composition of the population and how it has changed in the past and how it may change in the future is needed for making informed decisions about the future. Information about population is a critical part of planning because it directly relates to land needs such as housing, industry, stores, public facilities and services, and transportation. The California Department of Finance estimated the planning area population at 236,690 as of January 1, 2022.

Population changes are useful socio-economic indicators. A growing population generally indicates a growing economy, while a decreasing population signifies economic decline. Table 4-3 shows population for each city in the planning area from 2010 to 2022 (California Department of Finance 2023). The population of the planning area increased 20 percent from 2010 to 2022, with Dublin gaining 26,896 residents, Livermore gaining 5,181, and Pleasanton gaining 7,324.

Table 4-3. Annual Population Data
Population
Dublin* Livermore Pleasanton Tri-Valley Planning Area
2010 46,036 80,968 70,285 197,289
2011 46,408 81,948 70,813 199,169
2012 46,956 82,772 71,117 200,845
2013 50,079 83,768 71,153 205,000
2014 53,512 85,049 71,990 210,551
2015 56,014 86,368 73,776 216,158
2016 57,349 88,138 74,982 220,469
2017 59,686 89,648 75,916 225,250
2018 61,488 90,392 78,244 230,124
2019 63,890 90,769 78,840 233,499
2020 74,211 87,694 79,741 241,646
2021 73,209 87,388 78,924 239,521
2022 72,932 86,149 77,609 236,690
Source: (California Department of Finance 2023)
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4. Community Profile
4-13
DSRSD provides service to 26,237 potable water accounts, 473 recycled water accounts and 25,301 single-family residential wastewater tax roll assessments (excludes commercial, industrial and institutional accounts), with a current staff of 131. The District distributes drinking water to approximately 100,400 people and provides wastewater collection and treatment for approximately 168,600 people in Dublin, southern San Ramon and the city of Pleasanton.

Figure 4-8 shows the overall planning area and Alameda County population change from 1980 to 2020. Between 1980 and 2020, Alameda County’s population grew by 52.15 percent and the planning area’s population increased by 189.37 percent. Much of the growth in the planning area was between 1980 and 2000, though double-digit growth continues. Local growth still exceeds that of the county.

Source: (California Department of Finance 2023)
Figure 4-8. Alameda County vs. Planning Area Population Growth

4.5.2 Socially Vulnerable Groups
In general, the socially vulnerable populations are at greater risk from hazard events because of decreased resources or physical abilities. These vulnerable populations may vary from the general population in risk perception, living conditions, access to information before, during and after a hazard event, capabilities during an event, and access to resources for post-disaster recovery. Indicators of vulnerability—such as disability, age, poverty, and minority race and ethnicity—often overlap spatially and often in the geographically most vulnerable locations. Detailed spatial analysis to locate areas where there are higher concentrations of vulnerable community members would help to extend focused public outreach and education to these most vulnerable citizens. 39%
35%
28%
18%
22%
3%
16%
13%
5%
11%
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
1980 1990 2000 2010 2020
Population Change Over Period
Planning Area
Alameda County
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Age Distribution
As a group, the elderly are more apt to lack the physical and economic resources necessary for response to hazard events and are more likely to suffer health-related consequences making recovery slower. They are more likely to be vision, hearing, and/or mobility impaired, and more likely to experience mental impairment or dementia.

Additionally, the elderly are more likely to live in assisted-living facilities where emergency preparedness occurs at the discretion of facility operators. These facilities are typically identified as “critical facilities” by emergency managers because they require extra notice to implement evacuation. Elderly residents living in their own homes may have more difficulty accessing information or evacuating their homes and could be stranded in dangerous situations. This population group is more likely to need individualized medical attention, which may not be readily available during natural disasters due to isolation caused by the event. Specific planning attention for the elderly is an important consideration given the current aging of the American population.

Children under 14 are particularly vulnerable to disaster events because of their young age and dependence on others for basic necessities. Very young children may additionally be vulnerable to injury or sickness; this vulnerability can be worsened during a natural disaster because they may not understand the measures that need to be taken to protect themselves from hazards.

The overall age distribution for the planning area is shown in Figure 4-9.Based on the U.S. Census 2021 American Community Survey (ACS) 1-year estimates, 12.5 percent of the planning area’s population is 65 or older, compared to Alameda County’s average of 13.9 percent. The Census data also show that 4.28 percent of the under-65 population has disabilities of some kind and 4.1 percent of the entire population have an income below the poverty line. It is also estimated that 24.5 percent of the population is 18 or younger, compared to Alameda County’s average of 20.6 percent (U.S. Census 2022).

Race, Ethnicity and Language
Research shows that minorities are less likely to be involved in pre-disaster planning and experience higher mortality rates during a disaster event. Post-disaster recovery can be ineffective and is often characterized by cultural insensitivity. Since higher proportions of ethnic minorities live below the poverty line than the majority white population, poverty can compound vulnerability. According to the U.S. Census 2021 ACS 1-year estimates, the racial composition of the planning area is predominantly white (41.47 percent) and Asian (37.43 percent), with 1.93 percent Black or African American. Figure 4-10 shows the racial distribution in the planning area.

Census data also indicate that 16.3 percent of individuals in the planning area are Hispanic or Latino (of any race) and that 32.27 percent of the planning area population is foreign-born.

Individuals with Disabilities and Others with Access and Functional Needs The 2021 U.S. Census estimates that 42.5 million non-institutionalized people with disabilities and others with access and functional needs live in the U.S. This equates to about one-in-eight persons. This population is more likely to have difficulty responding to a hazard event than the general population. Local government is the first level of response to assist these individuals, and coordination of efforts to meet their needs is paramount to life safety efforts. Knowing the percentage of population with a disability or access and functional need will allow emergency management personnel and first responders to have personnel available who can provide services needed by this population. According to the 2021 ACS 1-year estimates, there are 19,360 individuals with some form of disability, access, or functional need within the planning area (U.S. Census 2022). 152

4. Community Profile
4-15
Source: (U.S. Census 2022)
Figure 4-9. Planning Area Age Distribution
Source: (U.S. Census 2022)
Figure 4-10. Planning Area Race Distribution
14,927
14,276
15,868
14,186
9,492
29,873
37,078
36,043
17,361
14,060
19,452
10,140
3,986
0 5,000 10,000 15,000 20,000 25,000 30,000 35,000 40,000 Under 5 years
5 to 9 years
10 to 14 years
15 to 19 years
20 to 24 years
25 to 34 years
35 to 44 years
45 to 54 years
55 to 59 years
60 to 64 years
65 to 74 years
75 to 84 years
85 years and over
Number of People
Age
White
42%
African American
2%
American Indian and
Alaska Native
1%
Asian
37%
Native Hawaiian and
Other Pacific
Islander
1%
Other
6%
Two or More Races
11%
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Income
In the United States, individual households are expected to use private resources to prepare for, respond to and recover from disasters to some extent. This expectation means that households living in poverty are automatically disadvantaged when confronting hazards. Additionally, the economically disadvantaged typically occupy more poorly built and inadequately maintained housing. Mobile or modular homes, for example, are more susceptible to damage in earthquakes and floods than other types of housing. In urban areas, the economically disadvantaged often live in older houses and apartment complexes, which are more likely to be made of unreinforced masonry, a building type that is particularly susceptible to damage during earthquakes.

Residents below the poverty level are less likely to have insurance to compensate for losses incurred from natural disasters. This means that residents below the poverty level have a great deal to lose during an event and are the least prepared to deal with potential losses. The events following Hurricane Katrina in 2005 illustrated that personal household economics significantly impact people’s decisions on evacuation. Individuals who cannot afford gas for their cars will likely decide not to evacuate.

Based on 2021 ACS 1-year estimates, average per capita income in the planning area in 2021 was $69,438 and the median household income was $160,198. As defined by the U.S. Census Bureau, the poverty threshold in 2021 was $27,479 for a household with two adults and two children, and $13,788 for one person (unrelated individual) (U.S. Census 2023)
2021 ACS 1-year estimates showed that roughly 15.4 percent of households in the planning area receive an income between $150,000 and $199,999 per year and about 39.6 percent of household incomes are above $200,000 annually. About 4.2 percent of the households in the planning area make less than $25,000 per year.

The Social Vulnerability Index
The Centers for Disease Control and Prevention’s Social Vulnerability Index (SVI) uses 16 U.S. census variables to help local officials identify communities that may need support before, during, or after disasters. Social vulnerability refers to the potential negative effects on communities caused by external stresses on human health.

Such stresses include natural or human-caused disasters or disease outbreaks. Reducing social vulnerability can decrease both human suffering and economic loss.

This planning effort aligns the social vulnerability threshold with that used in the State of California Hazard Mitigation Plan. High vulnerability is defined by using the overall summary ranking value greater than 0.70. A GIS analysis found that no Census tracts within the Tri-Valley planning area have an SVI of 0.7 or greater. The highest SVI value among the 44 planning area Census tracts is 0.54, and 39 of the Census tracts have an SVI less than 0.3. For this reason, the risk assessment in this plan provides qualitative discussions of how each hazard can affect socially vulnerable populations, but no quantitative analysis is provided of socially vulnerable populations at risk.

4.6 ECONOMY

4.6.1 Large Local Employers
The planning area benefits from a variety of business activity. Major businesses with headquarters in Dublin include Ross Stores, Challenge Dairy, Tria Beauty and DeSilva Gates Construction. Technology firms in Dublin 154

4. Community Profile
4-17
include Micro Dental Laboratories, Callidues Cloud, Carl Zeiss Meditec, and Epicor. Top employers in City of Livermore include Lawrence Livermore National Laboratory, Valley Care Health System Lifestyle Rx Fitness Center, Livermore Valley Joint Unified School District, Comcast Cable, and Sandia National Laboratory, and Form Factor, Inc., Gillig Bus, and Tesla warehouse. Top employers in City of Pleasanton include Kaiser Permanente, Safeway, Oracle, Workday Inc., Pleasanton Unified School District, Macy’s, and Valley Care Medical Center.

4.6.2 Employment by Sector
Figure 4-11 shows the planning area breakdown of employment by U.S. Census-defined industry types from 2021 ACS 1-year estimates. Professional, scientific, and management, and administrative and waste management services has the highest percentage of employees with 26.7 percent. Followed by educational services, and health care and social assistance with 21.37 percent.

Source: (U.S. Census 2022)
Figure 4-11. Industry in the Planning Area by Population Employed

4.6.3 Employment by Occupations
According to the 2021 ACS 1-year estimates, about 68 percent of the planning area’s population 16 years and over is in the labor force. Figure 4-12 shows the distribution of workers by occupation category.

4.6.4 Unemployment
Figure 4-13 compares California and planning area unemployment trends from 2016 through 2022.

Unemployment in the planning area has remained lower than the state average, and is lowest in 2022, at about

2.5 percent. Unemployment rates jumped significantly at the beginning of the COVID-19 pandemic in 2020, but have now been on the decline in both the state and the planning area.

0.53%

4.47%

10.00%

1.77%

9.73%

3.27%

3.33%

7.10%

26.27%

21.37%

6.20%

2.70%

3.27%
Agriculture, forestry, fishing and hunting, mining
Construction
Manufacturing
Wholesale trade
Retail trade
Transportation, warehousing, utilities
Information
Finance, insurance, real estate, rental and leasing
Professional, scientific, management, administrative, waste management Educational services, health care, social assistance
Arts, entertainment, recreation, accommodation, food services Other services
Public administration

0.00% 5.00% 10.00% 15.00% 20.00% 25.00% 30.00%
Industry Employment as % of Total
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Source: (U.S. Census 2022)
Figure 4-12. Occupations in the Planning Area
Source: CA EDD, 2022
Figure 4-13. California State and Planning Area Unemployment Rate The 2021 ACS 1-year estimates show that over 68 percent of the employed population 16 years and older in the planning area, or 129,137 individuals, commute to work. Of those, 47.17 percent drove alone (by car, truck or van) to work, and 7.27 percent carpooled (by car, truck or van). The mean travel time to work in the planning area is about 29 minutes (U.S. Census 2022).

Service
10%
Management,
Business, Science,
Arts
63%
Natural Resources,
Construction,
Maintenance
4%
Production,
Transportation,
Material Moving…
Sales, Office
18%
4%
3%
3% 3%
7%
5%
3%
5%
6%
6% 5%
10%
8%
5%
0%
2%
4%
6%
8%
10%
12%
2016 2017 2018 2019 2020 2021 2022
Population Change Over PPeriod
Planning Area
California
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5. HAZARDS OF CONCERN
Defining the hazards that present the greatest risk to the planning area is the first step in assessing overall risk to the community. The planning team and Steering Committee reviewed available information to determine what types of hazards may affect the planning area, how often they can occur, and their potential severity. This effort defined hazards of concern, for which individual risk assessments are presented in this hazard mitigation plan.

5.1 MAJOR PAST HAZARD EVENTS
A list of federal disaster declarations that affected the planning area offers an indication of the types of hazards most likely to pose risks to the community. Federal disaster declarations are typically issued for hazard events that cause more damage than state and local governments can handle without assistance from the federal government, although no specific dollar loss threshold has been established for these declarations. A federal disaster declaration puts federal recovery programs into motion to help disaster victims, businesses, and public entities.

Some of the programs are matched by state programs. Since 1953, 20 presidential disaster declarations have been issued for Alameda County, which includes the cities of Dublin, Livermore, and Pleasanton and DSRSD, as listed in Table 5-1.

Table 5-1. Presidential Disaster Declarations
Type of Event FEMA Disaster Number Declaration Date
Severe Winter Storms, Flooding, Landslides, and Mudslides DR-4683 January 14, 2023 COVID-19 Pandemic DR-4482 March 22, 2020
Severe Winter Storms, Flooding, Mudslides DR-4308 April 1, 2017 Severe Winter Storms, Flooding, Mudslides DR-4305 March 16, 2017 Severe Winter Storms, Flooding, Mudslides DR-4301 February 14, 2017 Severe Winter Storms, Flooding, Landslides, Mud Flows DR-1646 June 5, 2006 Severe Winter Storms, Flooding, Landslides, Mud Flows DR-1628 February 3, 2006 Severe Winter Storms, Flooding DR-1203 February 9, 1998 Severe Winter Storms, Flooding DR-1155 January 4, 1997
Severe Winter Storms, Flooding, Landslides, Mud Flows DR-1046 March 12, 1995 Severe Winter Storms, Flooding, Landslides, Mud Flows DR-1044 January 10, 1995 Oakland Hills Fire DR-919 October 22, 1991
Severe Freeze DR-894 February 11, 1991
Loma Prieta Earthquake DR-845 October 17, 1989
Severe Storms, Flooding DR-758 February 12, 1986
Coastal Storms, Floods, Slides, Tornadoes DR-677 January 21, 1983 Severe Storms, Flood, Mudslides, High Tide DR-651 January 7, 1982 Drought EM-3023 January 20, 1977
Forest, Brush Fires DR-295 September 29, 1970
Severe Storms, Flooding DR-283 February 16, 1970
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Source: (FEMA 2017); (FEMA 2022)
Review of these events helps identify targets for risk reduction and ways to increase a community’s capability to mitigate damage from large-scale events in the future. Still, many natural hazard events do not trigger federal disaster declaration protocol but have significant impacts on their communities. These events are also important to consider in establishing recurrence intervals for hazards of concern.

5.2 HAZARDS IDENTIFIED FOR ASSESSMENT IN THIS PLAN
The Steering Committee considered the full range of natural and human-caused hazards assessed in the 2023 State of California Hazard Mitigation Plan (draft) that could affect the planning area and then listed hazards that present the greatest concerns for the Tri-Valley planning area (see Table 5-2). The process incorporated a review of local hazard planning documents as well as information on the frequency of, magnitude of, and costs associated with hazards that have struck the planning area or could do so. Anecdotal information regarding natural hazards and the perceived vulnerability of the planning area’s assets to them was also used. Based on the review, this plan presents complete risk assessment for the following hazards of concern (presented in alphabetical order; the order of listing does not indicate the hazards’ relative severity):
• Climate change
• Dam failure
• Drought
• Earthquake
• Flood
• Landslide
• Severe weather
• Wildfire
In addition to the hazards of concern for which full risk assessments were performed, the following hazards of interest were identified for inclusion in this plan:
• Active threats
• Civil unrest
• Cyber threats
• Hazardous materials incidents
• Pipeline and utility failure
• Public health emergency
• Terrorism
• Transportation accidents
These hazards are of interest because they present risk to the planning area. However, no methodologies are currently available to perform risk assessments on them that are equivalent to those used for the natural hazards of concern addressed in detail in this plan.
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5-3
Table 5-2. Tri-Valley Hazard Comparison with California State Hazards Hazard Assessed in 2023
California State Hazard
Mitigation Plan (Draft)
Where Addressed in
2023 Tri-Valley Hazard
Mitigation Plan
Comment
Air pollution Wildfire This hazard is included in the discussion of wildfire Civil disorder Human-caused hazards This hazard is included in a combined discussion of human-caused hazards (referred to as civil unrest)
Cyber threats Human-caused hazards This hazard is included in a combined discussion of human-caused hazards Dam failure Dam failure This hazard aligns with the state Drought Drought This hazard aligns with the state
Earthquake Earthquake This hazard aligns with the state Electromagnetic pulse attack Human-caused hazards This hazard is included in a combined discussion of terrorism (under human-caused hazards)
Energy shortage Not included This hazard is a concern for the planning area, but it is dealt with through other planning mechanisms
Epidemic/pandemic/vectorborne diseasePublic health emergency This hazard is included in a combined discussion of public health emergencies
Extreme cold or freeze Not included This hazard is not a concern for the planning area Extreme heat Severe weather This hazard is included in a combined discussion of severe weather hazards Geomagnetic storm (space
weather)
Severe weather This hazard is included in a combined discussion of severe weather hazards Hazardous materials release Human-caused hazards This hazard is included in a combined discussion of human-caused hazards Invasive and nuisance species Not included This hazard is not a concern for the planning area Landslide, debris flow, and
other mass movements
Landslide This hazard aligns with the state
Levee failure Not included This hazard is not a concern for the planning area Natural gas pipeline hazards Human-caused hazards This hazard is included in a combined discussion of human-caused hazards Oil spills Not included This hazard is not a concern for the planning area Other potential causes of longterm electrical outageNot included This hazard is not a concern for the planning area Public safety power shutoff Severe weather This hazard is discussed in connection with the severe weather hazard Radiological accidents Human-caused hazards This hazard is mentioned in connection with hazardous materials incidents Riverine, stream and alluvial
flood
Flood The flood chapter addresses stormwater runoff floods, riverine floods and flash floods
Sea-level rise, coastal flooding
and erosion
Climate change This hazard is included in a combined discussion of hazards and factors relating to climate change
Severe wind, weather, and
storms
Severe weather This hazard is included in a combined discussion of severe weather hazards Snow avalanche Not included This hazard is not a concern for the planning area Subsidence Not included This hazard is not a concern for the planning area Terrorism Human-caused hazards This hazard is included in a combined discussion of human-caused hazards Transportation accidents
resulting in explosions or toxic
releases
Human-caused hazards This hazard is included in a combined discussion of severe weather hazards Tree mortality Climate change This hazard is briefly mentioned in a combined discussion of climate change Tsunami and seiche Not included The planning area does not border the ocean or contain any large bodies of water
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Hazard Assessed in 2023
California State Hazard
Mitigation Plan (Draft)
Where Addressed in
2023 Tri-Valley Hazard
Mitigation Plan
Comment
Urban structural fire Not included This hazard is a concern for the planning area, but it is dealt with in other planning mechanisms
Volcano Not included This hazard is not a concern for the planning area Well stimulation and hydraulic
fracturing
Not included This hazard is not occurring in the planning area Wildfire Wildfire This hazard aligns with the state
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6. RELEVANT LAWS, ORDINANCES AND PROGRAMS
Existing regulations, agencies and programs at the federal, state, and local level can support or impact hazard mitigation actions identified in this plan. Hazard mitigation plans are required to include a review and incorporation, if appropriate, of existing plans, studies, reports, and technical information as part of the planning process (44 CFR, Section 201.6(b)(3)). Information presented in this section can be used to review local capabilities to implement the action plan this hazard mitigation plan presents. Individual review by each planning partner of existing local plans, studies, reports, and technical information is presented in the annexes in Volume 2.

6.1 RELEVANT FEDERAL AND STATE AGENCIES, PROGRAMS AND

REGULATIONS
State and federal regulations and programs that need to be considered in hazard mitigation are constantly evolving. For this plan, a review was performed to determined which regulations and programs are currently most relevant to hazard mitigation planning. The findings are summarized in Table 6-1 and Table 6-2. Short descriptions of each program are provided in Appendix B.

Table 6-1. Summary of Relevant Federal Agencies, Programs and Regulations Agency, Program or Regulation Hazard Mitigation
Area Affected Relevance
Americans with Disabilities Act Action Plan
Implementation
FEMA hazard mitigation project grant applications require full compliance with applicable federal acts.

Bureau of Land Management Wildfire Hazard The Bureau funds and coordinates wildfire management programs and structural fire management and prevention on BLM lands.

Civil Rights Act of 1964 Action Plan
Implementation
FEMA hazard mitigation project grant applications require full compliance with applicable federal acts.

Clean Water Act Action Plan
Implementation
FEMA hazard mitigation project grant applications require full compliance with applicable federal acts.

Community Development Block
Grant Disaster Resilience
Program
Action Plan Funding This is a potential alternative source of funding for actions identified in this plan.

Community Rating System Flood Hazard This voluntary program encourages floodplain management activities that exceed the minimum National Flood Insurance Program requirements.

Disaster Mitigation Act Hazard Mitigation
Planning
This is the current federal legislation addressing hazard mitigation planning.

Emergency Relief for Federally
Owned Roads Program
Action Plan Funding This is a possible funding source for actions identified in this plan.

Emergency Watershed Program Action Plan Funding This is a possible funding source for actions identified in this plan.

Endangered Species Act Action Plan
Implementation
FEMA hazard mitigation project grant applications require full compliance with applicable federal acts.
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Agency, Program or Regulation Hazard Mitigation
Area Affected Relevance
Federal Energy Regulatory
Commission Dam Safety
Program
Dam Failure Hazard This program cooperates with a large number of federal and state agencies to ensure and promote dam safety.

Federal Wildfire Management
Policy and Healthy Forests
Restoration Act
Wildfire Hazard These documents mandate community-based collaboration to reduce risks from wildfire.

National Dam Safety Act Dam Failure Hazard This act requires a periodic engineering analysis of most dams in the country National Environmental Policy
Act
Action Plan
Implementation
FEMA hazard mitigation project grant applications require full compliance with applicable federal acts.

National Fire Plan (2001) Wildfire Hazard This plan calls for joint risk reduction planning and implementation by federal, state and local agencies.

National Flood Insurance
Program (NFIP)
Flood Hazard This program makes federally backed flood insurance available to homeowners, renters, and business owners in exchange for communities enacting floodplain regulations
National Incident Management
System (NIMS)
Action Plan
Development
Adoption of this system for government, nongovernmental organizations, and the private sector to work together to manage incidents involving hazards is a prerequisite for federal preparedness grants and awards National Landslide
Preparedness Act
Risk Assessment of
Landslide Hazard
This act authorized a national landslide hazards reduction program and a 3D elevation program, providing tools and data to assess the landside hazard.

Presidential Executive Order
11988 (Floodplain Management)
Flood Hazard This order requires federal agencies to avoid long and short-term adverse impacts associated with modification of floodplains
Presidential Executive Order
11990 (Protection of Wetlands)
Action Plan
Implementation
FEMA hazard mitigation project grant applications require full compliance with applicable presidential executive orders.

U.S. Army Corps of Engineers
Dam Safety Program
Dam Failure Hazard This program is responsible for safety inspections of dams that meet size and storage limitations specified in the National Dam Safety Act.

U.S. Army Corps of Engineers
Flood Hazard Management
Flood Hazard, Action
Plan Implementation,
Action Plan Funding
The Corps of Engineers offers multiple funding and technical assistance programs available for flood hazard mitigation actions
U.S. Fire Administration Wildfire Hazard This agency provides leadership, advocacy, coordination, and support for fire agencies and organizations.

U.S. Fish and Wildlife Service Wildfire Hazard This service’s fire management strategy employs prescribed fire throughout the National Wildlife Refuge System to maintain ecological communities. 162

6. Relevant Laws, Ordinances and Programs
6-3
Table 6-2. Summary of Relevant State Agencies, Programs and Regulations Agency, Program or Regulation Hazard Mitigation
Area Affected Relevance
AB 9: Fire safety: Wildfires: Fire
Adapted Communities
Wildfire Hazard Establishes the Regional Forest and Fire Capacity Program to support regional leadership to build local and regional capacity and develop, prioritize, and implement strategies and projects that create fire-adapted communities and landscapes by improving watershed health, forest health, community wildfire preparedness, and fire resilience.

AB 32: The California Global
Warming Solutions Act
Action Plan
Development
Establishes a state goal of reducing greenhouse gas emissions.

AB 38: Fire safety: Low-Cost
Retrofits: Regional Capacity
Review: Wildfire Mitigation
Wildfire Hazard Directs the California Natural Resources Agency to review the regional capacity of each county that contains a very high fire hazard severity zone and establishes a comprehensive wildfire mitigation and assistance program.

AB 70: Flood Liability Flood Hazard A city or county may be required to partially compensate for property damage caused by a flood if it unreasonably approves new development in areas protected by a state flood control project
AB 162: Flood Planning Flood Hazard Cities and counties must address flood-related matters in the land use, conservation, and safety and housing elements of their general plans.

AB 267: California Environmental
Quality Act: Exemption:

Prescribed Fire, Thinning, and
Fuel Reduction Projects.

Wildfire Hazard Extends to January 1, 2026, the exemption from requirements of the California Environmental Quality Act for prescribed fire, thinning, or fuel reduction projects on federal lands to reduce the risk of high-severity wildfire that had been reviewed under the National Environmental Policy Act.

AB 380: Forestry: Priority Fuel
Reduction Projects
Wildfire Hazard Requires the Department of Forestry and Fire Protection to identify priority fuel reduction projects annually and exempts the identified priority fuel reduction projects from certain legal requirements.

AB 431: Forestry: Timber
Harvesting Plans: Defensible
Space: Exemptions
Wildfire Hazard Extends to January 1, 2026, the exemption from a requirement to complete a timber harvest plan for maintaining defensible space between 150 feet and 300 feet from a habitable structure.

AB 497: Forestry and Fire
Protection: Local Assistance
Grant Program: Fire Prevention
Activities: Street and Road
Vegetation Management
Wildfire Hazard Appropriates funds for local assistance grants for fire prevention activities with priority for projects that manage vegetation along streets and roads to prevent the ignition of wildfire.

AB 575: Civil Liability: Prescribed
Burning Activities: Gross
Negligence
Wildfire Hazard Provides that a private entity engaging in a prescribed burning activity that is supervised by a person certified as burn boss is liable for damages to a third party only if the prescribed burning activity was carried out in a grossly negligent manner.

AB 642: Wildfires Wildfire Hazard Makes changes to support cultural and prescribed fire, including the creation of a Cultural Burning Liaison at the Department of Forestry and Fire Protection, and requires a proposal for creating a prescribed fire training center.

AB 747: General Plans—Safety
Element
Hazard Mitigation
Planning
The safety elements of cities’ and counties’ general plans must address evacuation routes and include any new information on flood and fire hazards and climate adaptation and resiliency strategies.

AB 800: Wildfires: local general
plans: safety elements: fire
hazard severity zones.

Wildfire Hazard Establishes provisions for wildfire hazard mapping and applications for that mapping in General Plan Safety Elements.

AB 1255: Fire prevention:

Department of Forestry and Fire
Protection: Grant Programs
Wildfire Hazard Requires the Natural Resources Agency to develop a guidance document that describes goals, approaches, opportunities, and best practices in each region of the state for ecologically appropriate, habitat-specific fire risk reduction.

Requires consultation with counties related to the Department of Forestry and Fire Protection’s local fire prevention grant program.
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Agency, Program or Regulation Hazard Mitigation
Area Affected Relevance
AB 1295: Residential development
Agreements: Very High-Risk Fire
Areas
Wildfire Hazard Prohibits the legislative body of a city or county from entering into a residential development agreement for property in a very high fire risk area as designated by a local agency or a fire hazard severity zone classified by the director of CAL FIRE.

AB 1439: Property Insurance
Discounts
Wildfire Hazard Requires residential or commercial property insurance policies to include a discount if a local government where the insured property is located funds a local wildfire protection or mitigation program.

AB 1500: Safe Drinking Water,
Wildfire Prevention, Drought
Preparation, Flood Protection,
Extreme Heat Mitigation, and
Workforce Development Bond Act
of 2022.

Drought, Flood,
Extreme Heat and
Wildfire Hazards
Authorizes, upon voter approval, the issuance of bonds to finance projects for safe drinking water, wildfire prevention, drought preparation, flood protection, extreme heat mitigation, and workforce development programs.

AB 2140: General Plans—Safety
Element
Hazard Mitigation
Planning
Enables state and federal disaster assistance and mitigation funding to communities with compliant hazard mitigation plans.

AB 2800: Climate Change—
Infrastructure Planning
Action Plan
Development
Requires state agencies to take into account the impacts of climate change when developing state infrastructure.

Alquist-Priolo Earthquake Fault
Zoning Act
Earthquake Hazard Restricts construction of buildings used for human occupancy on the surface trace of active faults.

Board of Forestry and Fire
Protection Fire Safe Regulations
Wildfire Hazard The Fire Safe Regulations set the floor for fire safety standards for perimeters and access to residential, commercial, and industrial building construction.

California Department of Forestry
and Fire Protection (CAL FIRE)
Wildfire Hazard CAL FIRE has responsibility for wildfires in areas that are not under the jurisdiction of the Forest Service or a local fire organization.

California Department of Parks
and Recreation
Wildfire Hazard State Parks Resources Management Division has wildfire protection resources available to suppress fires on State Park lands.

California Department of Water
Resources
Flood Hazard Department of Water Resources is the state coordinating agency for floodplain management.

California Division of Safety of
Dams
Dam Failure
Hazard
Division of Safety of Dams monitors the dam safety program at the state level and maintains a working list of dams in the state.

California Environmental Quality
Act
Action Plan
Implementation
Establishes a protocol of analysis and public disclosure of the potential environmental impacts of development projects. Any project action identified in this plan will seek full California Environmental Quality Act compliance upon implementation.

California Fire Alliance Wildfire Hazard The alliance works with communities at risk from wildfires to facilitate the development of community fire loss mitigation plans.

California Fire Plan Wildfire Hazard This plan’s goal is to reduce costs and losses from wildfire through pre-fire management and through successful initial response.

California Fire Safe Council Wildfire Hazard This council facilitates the distribution of National Fire Plan grants for wildfire risk reduction and education.

California Fire Service and
Rescue Emergency Mutual Aid
Plan
Wildfire Hazard This plan provides guidance and procedures for agencies developing emergency operations plans, as well as training and technical support.

California General Planning Law Hazard Mitigation
Planning
This law requires every county and city to adopt a comprehensive long-range plan for community development, and related laws call for integration of hazard mitigation plans with general plans.

California Multi-Hazard Mitigation
Plan
Hazard Mitigation
Planning
Local hazard mitigation plans must be consistent with their state’s hazard mitigation plan.

California Residential Mitigation
Program
Earthquake Hazard This program helps homeowners with seismic retrofits to lessen the potential for damage to their houses during an earthquake.
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6. Relevant Laws, Ordinances and Programs
6-5
Agency, Program or Regulation Hazard Mitigation
Area Affected Relevance
California State Building Code Action Plan
Implementation
Local communities must adopt and enforce building codes, which include measures to improve buildings’ ability to withstand hazard events.

Disadvantaged and Low-Income
Communities Investments
Action Plan
Funding
This is a potential source of funding for actions located in disadvantaged or low-income communities.

Division of the State Architect’s
AB 300 List of Seismically At-Risk
Schools
Earthquake Hazard,
Action Plan
Development
The Division of the State Architect recommends that local school districts conduct detailed seismic evaluations of seismically at-risk schools identified in the inventory that was required by AB 300.

Governor’s Executive Order S-13-
08 (Climate Impacts)
Action Plan
Implementation
This order includes guidance on planning for climate change in designated coastal and floodplain areas for new projects.

Office of the State Fire Marshal Wildfire Hazard This office has a wide variety of fire safety and training responsibilities.

Senate Bill 12: Local government:
planning and zoning: wildfires.

Wildfire Hazard Requires safety elements to be reviewed and updated as necessary to include a retrofit strategy to reduce the risk of property loss and damage during wildfires. Requires the planning agency to submit the adopted strategy to the Office of Planning and Research for inclusion in a central clearinghouse.

Senate Bill 92: Dam Emergency
Action Plans; Public Resources
Portion of Biennial Budget Bill
Dam Failure
Hazard
This bill requires dams (except for low-risk dams) to have emergency action plans that are updated every 10 years and inundation maps updated every 10 years, or sooner if specific circumstances change.

Senate Bill 97: Guidelines for
Greenhouse Gas Emissions
Action Plan
Implementation
This bill establishes that greenhouse gas emissions and the effects of greenhouse gas emissions are appropriate subjects for California Environmental Quality Act analysis.

Senate Bill 99: General Plans:

Safety Element: Emergency
Evacuation Routes
Action Plan
Implementation
This bill requires the safety element to include information to identify residential developments in hazard areas that do not have at least two emergency evacuation routes.

Senate Bill 379: General Plans:

Safety Element—Climate
Adaptation
Action Plan
Implementation
This bill requires cities and counties to include climate adaptation and resiliency strategies in the safety element of their general plans.

Senate Bill 1000: General Plan
Amendments—Safety and
Environmental Justice Elements
Action Plan
Implementation
Under this bill, review and revision of general plan safety elements are required to address only flooding and fires (not climate adaptation and resilience), and environmental justice is required to be included in general plans.

Senate Bill 1241: General Plans:

Safety Element—Fire Hazard
Impacts
Wildfire Hazard This bill requires cities and counties to make findings regarding available fire protection and suppression services before approving a tentative map or parcel map.

Standardized Emergency
Management System
Action Plan
Implementation
Local governments must use this system to be eligible for state funding of response-related personnel costs.

Western Governors Association
Ten-Year Comprehensive Strategy
Wildfire Hazard This strategy implementation plan prepared by federal and Western state agencies outlines measures to restore fire-adapted ecosystems and reduce hazardous fuels.

6.2 LOCAL PLANS, REPORTS AND CODES
Plans, reports and other technical information were identified and provided directly by participating jurisdictions and stakeholders or were identified through independent research by the planning consultant. These documents were reviewed to identify the following:
• Existing jurisdictional capabilities.
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• Needs and opportunities to develop or enhance capabilities, which may be identified within the local mitigation strategies.
• Mitigation-related goals or objectives, considered during the development of the overall goals and objectives.
• Proposed, in-progress, or potential mitigation projects and actions to be incorporated into the updated jurisdictional mitigation strategies.

The following local regulations, codes, ordinances, and plans were reviewed in order to develop complementary and mutually supportive goals, objectives, and mitigation strategies that are consistent across local and regional planning and regulatory mechanisms:
• General plans (land use, housing, safety, and open space elements) • Building codes
• Zoning and subdivision ordinances
• National Flood Insurance Program flood damage prevention ordinances • Stormwater management plans
• Emergency management and response plans
• Land use and open space plans
• Climate action plans
• Community wildfire protection plans

6.3 LOCAL CAPABILITY ASSESSMENT
All participating jurisdictions compiled an inventory and analysis of existing authorities and capabilities called a “capability assessment.” A capability assessment creates an inventory of a jurisdiction’s mission, programs, and policies, and evaluates its capacity to carry them out. This assessment identifies potential gaps in the jurisdiction’s capabilities.

The planning partnership views all core jurisdictional capabilities as fully adaptable to meet a jurisdiction’s needs.

Every code can be amended, and every plan can be updated. Such adaptability is itself considered to be an overarching capability. If the capability assessment identified an opportunity to add a missing core capability or expand an existing one, then doing so has been selected as an action in the jurisdiction’s action plan, which is included in the individual annexes presented in Volume 2 of this plan.

Capability assessments for each planning partner are presented in the jurisdictional annexes in Volume 2. The sections below describe the specific capabilities evaluated under the assessment.

6.3.1 Legal and Regulatory Capabilities
Jurisdictions have the ability to develop policies and programs and to implement rules and regulations to protect and serve community members. Local policies are typically identified in a variety of community plans, implemented via a local ordinance, and enforced through a governmental body. 166

6. Relevant Laws, Ordinances and Programs
6-7
Jurisdictions regulate land use through the adoption and enforcement of zoning, subdivision, and land development ordinances, building codes, building permit ordinances, floodplain, and stormwater management ordinances. When effectively prepared and administered, these regulations can lead to hazard mitigation.

6.3.2 Fiscal Capabilities
Assessing a jurisdiction’s fiscal capability provides an understanding of the ability to fulfill the financial needs associated with hazard mitigation projects. This assessment identifies both outside resources, such as grantfunding eligibility, and local jurisdictional authority to generate internal financial capability, such as through impact fees.

6.3.3 Administrative and Technical Capabilities
Legal, regulatory, and fiscal capabilities provide the backbone for successfully developing a mitigation strategy; however, without appropriate personnel, the strategy may not be implemented. Administrative and technical capabilities focus on the availability of personnel resources responsible for implementing all the facets of hazard mitigation. These resources include technical experts, such as engineers and scientists, as well as personnel with capabilities that may be found in multiple departments, such as grant writers.

6.3.4 National Flood Insurance Program Compliance
Flooding is the costliest natural hazard in the United States and, with the promulgation of recent federal regulation, homeowners throughout the country are experiencing increasingly high flood insurance premiums.

Community participation in the National Flood Insurance Program (NFIP) opens up opportunity for additional grant funding associated specifically with flooding issues. Assessment of the jurisdiction’s current NFIP status and compliance provides planners with a greater understanding of the local flood management program, opportunities for improvement, and available grant funding opportunities.

6.3.5 Public Outreach Capability
Regular engagement with the public on issues regarding hazard mitigation provides an opportunity to directly interface with community members. Assessing this outreach and education capability illustrates the connection between the government and community members, which opens a two-way dialogue that can result in a more resilient community based on education and public engagement.

6.3.6 Participation in Other Programs
Other programs, such as the Community Rating System, StormReady, and Firewise USA, can enhance a jurisdiction’s ability to mitigate, prepare for, and respond to natural hazards. These programs indicate a jurisdiction’s desire to go beyond minimum requirements set forth by local, state, and federal regulations in order to create a more resilient community. These programs complement each other by focusing on communication, mitigation, and community preparedness to save lives and minimize the impact of natural hazards on a community.
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6.3.7 Development and Permitting Capability
Identifying previous and future development trends is achieved through a comprehensive review of permitting since completion of the previous plan and in anticipation of future development. Tracking previous and future growth in potential hazard areas provides an overview of increased exposure to a hazard within a community.

6.3.8 Adaptive Capacity
An adaptive capacity assessment evaluates a jurisdiction’s ability to anticipate impacts from future conditions. By looking at public support, technical adaptive capacity, and other factors, jurisdictions identify their core capability for resilience against issues such as climate change. The adaptive capacity assessment provides jurisdictions with an opportunity to identify areas for improvement by ranking their capacity high, medium, or low.

6.3.9 Integration Opportunity
The assessment looked for opportunities to integrate this mitigation plan with the legal/regulatory capabilities identified. Capabilities were identified as integration opportunities if they can support or enhance the actions identified in this plan or be supported or enhanced by components of this plan. Planning partners considered actions to implement this integration as described in their jurisdictional annexes.

6.4 OPPORTUNITIES FOR INTEGRATION AND EXPANSION
The Tri-Valley planning partners have a high degree of core capability for funding, administrative, and technical functions, and public outreach with its existing plans and programs. These capabilities represent opportunities for future integration with this hazard mitigation plan. All four jurisdictions in the Tri-Valley planning area have begun this integration process with the concurrent planning efforts for this hazard mitigation plan and the ongoing implementation and update of their general plans, specific integration for each planning partner is located in their respective annex in Volume 2. The planning partners are fully committed to implementing and incorporating the information learned during the update process in an emergency management plan integration process. This hazard mitigation plan includes information that can be used for future updates such as those listed in Table 6-3 identifies how this hazard mitigation plan incorporates information from other plans and programs and how its findings may be integrated into future updates of those plans and programs.

Table 6-3. Integration of Hazard Mitigation Plan With Other Plans and Programs Plan or Program Integration With Hazard Mitigation Plan Update [All jurisdictions]
General Plan
Livermore—Review safety elements to ensure compliance with current guidance incorporating information and data learned during the update process
Pleasanton—Review safety element to ensure compliance with current guidelines incorporating information and data learned during the update process
Dublin—Review safety element to ensure compliance with current guidelines incorporating information and data learned during the update process
DSRSD—Make appropriate updates as indicated into master plan incorporating information and data learned during the update process
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Plan or Program Integration With Hazard Mitigation Plan Update [All jurisdictions]
Climate Action Plan
Livermore—Incorporate data and findings from hazard mitigation plan to update plans and programs related to climate based on new information learned from this hazard mitigation plan update Pleasanton—Incorporate data and findings from hazard mitigation plan to update plans and programs related to climate based on new information learned from this hazard mitigation plan update Dublin—Incorporate data and findings from hazard mitigation plan to update plans and programs related to climate based on new information learned from this hazard mitigation plan update DSRSD—Update the District plan to be consistent with the changing climate conditions based on new information learned from this hazard mitigation plan update
Resilience Plan Incorporate relevant hazard mitigation plan action items into resiliency plans Emergency
Response and
Operation Plan
Livermore—Incorporate hazard risk ranking information to update emergency response and training and exercise plans
Pleasanton—Incorporate hazard risk ranking information to update emergency response and training and exercise plans
Dublin—Incorporate hazard risk ranking information to update emergency response and training and exercise plans; currently in process of updating the City’s EOP and emergency management efforts DSRSD—Update related Emergency Action Plans (EAP) based on finding from the risk ranking assessment; currently updating the District’s emergency management plans and responses Capital Improvement
Plan (CIP)
Livermore—Update CIP to include hazard mitigation plan related action items Pleasanton—Update CIP to include hazard mitigation plan related action items Dublin—Update CIP to include hazard mitigation plan related action items DSRSD—Update CIP to include hazard mitigation plan related action items Municipal Codes Livermore—Review and update existing codes and regulation (building, zoning, and planning) and incorporate possible related action items for future action
Pleasanton—Review and update existing codes and regulation (building, zoning, and planning) and incorporate possible related action items for future action
Dublin—Review and update existing codes and regulation (building, zoning, and planning) and incorporate possible related action items for future action
DSRSD—Not applicable (special district)
Community Design
Guidelines
Livermore—Update city guidelines as warranted based upon any new information or data gained while conducting hazard mitigation plan update
Pleasanton—Update city guidelines as warranted based upon any new information or data gained while conducting hazard mitigation plan update
Dublin—Update city guidelines as warranted based upon any new information or data gained while conducting hazard mitigation plan update
DSRSD—Not applicable (special district)
Water Efficient
Landscape Design
Guidelines
Livermore—Make necessary regulation changes and updates based on changing climate and information derived from hazard mitigation plan update
Pleasanton—Make necessary regulation changes and updates based on changing climate and information derived from hazard mitigation plan update
Dublin—Make necessary regulation changes and updates based on changing climate and information derived from hazard mitigation plan update
DSRSD—Collaborate with municipalities in service area to update landscape design and watering guidance Stormwater
Management
Programs
Livermore—As an NFIP/CRS community, make any necessary updated changes in plans and programs based on information derived from the flooding information in the hazard mitigation plan Pleasanton—As an NFIP/CRS community, make any necessary updated changes in plans and programs based on information derived from the flooding information in the hazard mitigation plan Dublin—Make any necessary updated changes in plans and programs based on information derived from the flooding information in the hazard mitigation plan
DSRSD—Update related EAPs and collaborate with municipalities in the service area on stormwater-related programs based on information derived from hazard mitigation plan update 169
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Plan or Program Integration With Hazard Mitigation Plan Update Water System
Vulnerability
Assessments
Livermore—Work with Public Works Department to ensure assessments are consistent with ever-changing water availability and the security of water delivery program Pleasanton—Work with Public Works Department to ensure assessments are consistent with ever-changing water availability and the security of water delivery program Dublin—Collaborate with DSRSD on water deliver program and system security DSRSD—Work with service area municipalities, including Dublin, on the delivery and security of the water system Master Fire
Protection Plans
Livermore—Continue work with the Livermore Pleasanton Fire Department (LPFD) to ensure the protection, prevention and suppression plans are current and that the LPFD collaborates with the building department on building plan reviews to be consisted with the current state building code Pleasanton— Continue work with the LPFD to ensure the protection, prevention and suppression plans are current and that the LPFD collaborates with the building department on building plan reviews to be consisted with the current state building code
Dublin—Continue work with the Alameda County Fire Department (ACFD) to ensure protection, prevention, and suppression plans are current and that the ACFD collaborates with the planning department on plan reviews to be consistent with the current state building code
DSRSD—Not applicable (special water district)
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PART 2—RISK ASSESSMENT
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7. RISK ASSESSMENT METHODOLOGY
The risk assessments in this plan describe the risks associated with each identified hazard of concern. The following steps were used to define the risk of each hazard:
• Identify and profile each hazard—The following information is given for each hazard:
➢ A summary of past events that have impacted the planning area ➢ Geographic areas most affected by the hazard
➢ Event frequency estimates
➢ Severity descriptions
➢ Warning time likely to be available for response.
• Determine exposure to each hazard—Exposure was assessed by overlaying hazard maps with an inventory of structures, facilities, and systems to decide which of them would be exposed to each hazard. • Assess the vulnerability of exposed facilities—Vulnerability of exposed structures and infrastructure was evaluated by interpreting the probability of occurrence of each event and assessing structures, facilities, and systems that are exposed to each hazard. Tools such as GIS and Hazus were used for this assessment for the dam failure, earthquake, flood, and tsunami hazards. Outputs similar to those from Hazus were generated for other hazards, using data generated through GIS.

The risk assessments performed for this plan evaluated risk for all participating incorporated areas. The assessments did not extend to the portion of the Dublin San Ramon Services District outside the three cities, because the District does not have the same regulatory authorities as cities in terms of mitigating risks to people and development.

7.1 RISK ASSESSMENT TOOLS

7.1.1 Mapping
National, state, and local databases were reviewed to locate spatially based data relevant to this planning effort.

Maps were produced using geographic information system (GIS) software to show the spatial extent and location of identified hazards when such data was available. These maps are included in the hazard profile chapters of this document and the jurisdiction-specific annexes in Volume 2. Information regarding the data sources and methodologies employed in these mapping efforts is located in Appendix C. 173
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7.1.2 Hazus
Overview
FEMA developed the standardized GIS-based software program Hazards U.S. (Hazus) to estimate losses caused by earthquakes, hurricanes and floods and identify areas that face the highest risk and potential for loss. Hazus is used to support risk assessments, mitigation planning, and emergency planning and response. It provides a wide range of inventory data, such as demographics, building stock, critical facilities, and transportation and utility infrastructure, and multiple models to estimate potential losses from natural disasters. The program maps and calculates hazard data and damage and economic loss estimates for buildings and infrastructure. Its advantages include the following:
• Provides a consistent methodology for assessing risk across geographic and political entities. • Provides a way to save data so that they can readily be updated as population, inventory, and other factors change and as mitigation planning efforts evolve.
• Facilitates review of mitigation plans because it helps to ensure that FEMA methodologies are incorporated.
• Supports grant applications by calculating benefits using FEMA definitions and terminology. • Produces hazard data and loss estimates that can be used in communication with local stakeholders. • Is administered by the local government and can be used to manage and update a hazard mitigation plan throughout its implementation.

For flood-related hazards, Hazus calculates losses to structures due to inundation based on depth of flooding and type of structure. Using historical flood insurance claim data, Hazus estimates the percentage of damage to structures and their contents by applying established damage functions to an inventory. The Hazus analysis also estimates the quantity of debris that would be caused by the flooding.

For earthquake, once the location and size of a hypothetical earthquake are identified, Hazus estimates the intensity of the ground shaking, the number of buildings damaged, the number of casualties, the damage to transportation systems and utilities, the number of people displaced from their homes, and the estimated cost of repair and clean up.

Levels of Detail for Evaluation
Hazus provides default data for inventory, vulnerability and hazards; this default data can be supplemented with local data to provide a more refined analysis. The model can carry out three levels of analysis, depending on the format and level of detail of information about the planning area:
• Level 1—All of the information needed to produce an estimate of losses is included in the software’s default data. This data is derived from national databases and describes in general terms the characteristic parameters of the planning area.
• Level 2—More accurate estimates of losses require more detailed information about the planning area.

Level 2 estimates of losses require detailed information on local geology, hydrology, hydraulics, building inventory, utilities, and critical facilities. This information is needed in a GIS format. • Level 3—This level of analysis generates the most accurate estimate of losses. It requires detailed engineering and geotechnical information to customize it for the planning area. 174

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7.2 RISK ASSESSMENT APPROACH

7.2.1 Hazard Profile Development
Hazard profiles were developed through web-based research and review of previously developed reports and plans, including community general plans and state and local hazard mitigation plans. Frequency and severity indicators include past events and the expert opinions of geologists, emergency management specialists, and others.

7.2.2 Exposure and Vulnerability
The risk assessment for this plan determined exposure and vulnerability to identified hazards of concern for the overall planning area and individual cities. The approach used for each hazard is described below.

Flood, Dam Failure, and Earthquake
Exposure and vulnerability to flood, dam failure, and earthquake were evaluated using Hazus as follows:
• Flood—A Level 2 user-defined analysis was performed for general building stock in flood zones and for critical facilities. Current flood mapping for the planning area was used to delineate flood hazard areas and estimate potential losses from the 1-percent-annual-chance and 0.2-percent-annual-chance flood events. To estimate damage that would result from a flood, Hazus uses pre-defined relationships between flood depth at a structure and resulting damage, with damage given as a percent of total replacement value. Curves defining these relationships have been developed for damage to structures and for damage to typical contents within a structure. By inputting flood depth data and known property replacement cost values, dollar-value estimates of damage were generated. • Dam Failure—A Level 2 user-defined analysis was performed for general building stock and critical facilities located in the dam failure hazard area. A depth grid was generated using a combined dam failure inundation area and uploaded into the Hazus riverine flood model. By inputting depth data and known property replacement cost values, dollar-value estimates of damage were generated. • Earthquake—A Level 2 analysis was performed to assess earthquake exposure and vulnerability for the following scenario events:
➢ A Magnitude 6.86 event on the Calaveras North Fault
➢ A Magnitude 6.86 event on the Greenville North Fault
➢ A Magnitude 7.05 event on the Hayward Fault (the USGS scenario representing this event is called the HayWired scenario)
➢ A Magnitude 6.5 event on the Las Positas Fault
➢ A Magnitude 6.5 event on the Mount Diablo Thrust South Fault All Other Assessed Hazards
Historical datasets were not adequate to model future losses for most of the hazards of concern. However, areas and inventory susceptible to some of the hazards of concern were mapped by other means, and exposure was evaluated. A qualitative analysis was conducted for other hazards using the best available data and professional judgment.
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7.3 SOURCES OF DATA USED IN MODELING

7.3.1 Building and Cost Data
Replacement cost values and detailed structure information derived from parcel and tax assessor data provided by Alameda County were loaded into Hazus. When available, an updated inventory was used in place of the Hazus defaults for critical facilities.

Replacement cost is the cost to replace the entire structure with one of equal quality and utility. Replacement cost is based on industry-standard cost-estimation models published in the 2022 edition of RS Means Square Foot Costs. It is calculated using the RS Means square foot cost for a structure, which is based on the Hazus occupancy class (i.e., multi-family residential or commercial retail trade), multiplied by the square footage of the structure from the tax assessor data. The construction class and number of stories for single-family residential structures also factor into determining the square-foot costs.

7.3.2 Hazus Data Inputs
The following hazard datasets were used for the Hazus Level 2 analysis conducted for the risk assessment:
• Flood—The effective Digital Flood Insurance Rate Map (DFIRM) for the planning area was used to delineate flood hazard areas and estimate potential losses from the 1-percent-annual-chance and

0.2-percent-annual-chance flood events.
• Dam Failure—Dam failure inundation areas were downloaded from the California Department of Water Resources for the Del Valle and Patterson Dams.
• Earthquake—Earthquake shake maps prepared by the USGS were used for the analysis of this hazard.

Data from the California Geological Survey on National Earthquake Hazard Reduction Program soil types and liquefaction zones were also integrated into the Hazus model.

7.3.3 Other Local Hazard Data
Locally relevant information on hazards was gathered from a variety of sources. Frequency and severity indicators include past events and the expert opinions of geologists, emergency management specialists, and others. Data sources for specific hazards were as follows:
• Landslide—Susceptibility to deep-seated landslides data were provided by the California Geological Survey. Areas categorized as very high susceptibility, high susceptibility, and medium susceptibility were used in the exposure analysis.
• Wildfire— Wildfire hazard severity zones from the California Department of Forestry and Fire Protection were used in the exposure analysis.

7.3.4 Data Source Summary
Table 7-1 summarizes the data sources used for the risk assessment for this plan. 176

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Table 7-1. Risk Assessment Data Sources
Data Source Date Format
Parcels (included county tax
assessor information such as use
code, year built, and building square
footage)
Alameda County, City of Pleasanton, City of Dublin 2022 Digital (GIS) Building Outlines City of Livermore, City of Pleasanton, City of Dublin 2022 Digital (GIS) Building replacement (square foot)
costs
RS Means 2022 Digital (pdf)
California State dam breach
inundation maps (inundation
boundaries and depth grids)
California Department of Water Resources 2019 Digital (GIS) ShakeMap – Calaveras (No) M6.86 USGS 2017 Digital (GIS) ShakeMap – Greenville (No) M6.86 USGS 2017 Digital (GIS) ShakeMap – HayWired M7.05 USGS 2018 Digital (GIS)
ShakeMap – Las Positas M6.5 USGS 2017 Digital (GIS)
ShakeMap – Mount Diablo Thrust
South M6.5
USGS 2017 Digital (GIS)
National Earthquake Hazards
Reduction Program soil mapping
(VsMapV3_Geology)
California Department of Conservation 2015 Digital (GIS) Liquefaction Susceptibility USGS Unknown Digital (GIS)
Digital Flood Insurance Rate Map
(DFIRM) – Alameda County effective
12/21/2018
FEMA 2018 Digital (GIS)
Susceptibility to deep-seated
landslides
California Geological Survey 2011 Digital (GIS)
Police Stations/Law Enforcement City of Pleasanton, Alameda County, Hazus Provided 2022 Digital (GIS) Fire Stations/Firefighting Resources City of Pleasanton, City of Livermore, Alameda County Fire Provided 2022 Digital (GIS) Schools City of Pleasanton, Alameda County Provided 2022 Digital (GIS) Historic/Cultural Resources City of Livermore, City of Dublin Provided 2022 Digital (GIS) Public Facilities City of Pleasanton Provided 2022 Digital (GIS) Senior Centers City of Dublin Provided 2022 Digital (GIS) Potable Water Facilities Dublin San Ramon Services District Provided 2022 Digital (GIS) Water Utilities City of Pleasanton, City of Livermore Provided 2022 Digital (GIS) Wastewater Treatment Plants CA State Geoportal Downloaded 2022 Digital (GIS) Dublin San Ramon Services District
Wastewater Facilities
Dublin San Ramon Services District Provided 2022 Digital (GIS) Sewer System Utilities City of Pleasanton, City of Livermore Provided 2022 Digital (GIS) Recycled Water Facilities Dublin San Ramon Services District Provided 2022 Digital (GIS) Community Shelters City of Pleasanton Provided 2022 Digital (GIS) Hospitals Alameda County Provided 2022 Digital (GIS)
Medical Facilities Hazus Downloaded 2022 Digital (GIS)
Veterans Health Medical Facilities Homeland Infrastructure Foundation-Level Data Downloaded 2022 Digital (GIS) Pharmacies Open Street Map Downloaded 2022 Digital (GIS) EMS Stations Homeland Infrastructure Foundation-Level Data Downloaded 2022 Digital (GIS) Health Facilities California Department of Public Health Downloaded 2022 Digital (GIS) 177
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Data Source Date Format
California Power Plants CA State Geoportal, Alameda County Downloaded 2022 Digital (GIS) Natural Gas Stations CA Energy Commission Downloaded 2022 Digital (GIS) National Gas Pipelines Homeland Infrastructure Foundation-Level Data Downloaded 2022 Digital (GIS) Wireless Facilities Homeland Infrastructure Foundation-Level Data, Alameda County, City of Dublin
Downloaded and
Provided 2022
Digital (GIS)
Broadcast Facilities (TV and Radio) Homeland Infrastructure Foundation-Level Data Downloaded 2022 Digital (GIS) Banks Homeland Infrastructure Foundation-Level Data Downloaded 2022 Digital (GIS) Highways City of Livermore, City of Dublin Provided 2022 Digital (GIS) Local Streets City of Livermore, City of Dublin Provided 2022 Digital (GIS) Railroad Facilities California Transportation, City of Dublin Downloaded and Provided 2022
Digital (GIS)
Airports California Transportation, Alameda County Downloaded and Provided 2022
Digital (GIS)
Bus Facilities City of Dublin, City of Livermore, California Sate Geoportal Downloaded and Provided 2022
Digital (GIS)
Port Facilities Homeland Infrastructure Foundation-Level Data, California Transportation
Downloaded 2022 Digital (GIS)
Bridges California Transportation, City of Livermore, City of Dublin Downloaded and Provided 2022
Digital (GIS)
Hazardous Materials Facilities City of Livermore, EPA Downloaded and Provided 2022
Digital (GIS)

7.4 LIMITATIONS
Loss estimates, exposure assessments, and hazard-specific vulnerability evaluations rely on the best available data and methodologies. Uncertainties are inherent in any loss estimation methodology and arise in part from incomplete scientific knowledge concerning natural hazards and their effects on the built environment.

Uncertainties also result from the following:
• Approximations and simplifications necessary to conduct a study • Incomplete or outdated inventory, demographic or economic parameter data • The unique nature, geographic extent, and severity of each hazard • Mitigation measures already employed
• The amount of advance notice residents have to prepare for a specific hazard event • The uncertain spatial accuracy of the dam inundation area data.

These factors can affect loss estimates by a factor of two or more. Therefore, potential exposure and loss estimates are approximate and should be used only to understand relative risk. Over the long term, the planning partners will collect additional data to assist in estimating potential losses associated with other hazards. 178
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8. DAM FAILURE

8.1 GENERAL BACKGROUND

8.1.1 Definition
A dam is an artificial barrier that can store water, wastewater, or liquid-borne materials for many reasons—flood control, human water supply, irrigation, livestock water supply, energy generation, containment of mine tailings, recreation, or pollution control. Many dams fulfill a combination of these functions. In California, dams are regulated by the State of California Division of Safety of Dams. Additional regulatory oversight of dams is described in Appendix B. The California Water Code defines a dam as any artificial barrier, together with appurtenant works, that does or may impound or divert water, and that meets either of the following conditions:
• Is 25 feet or more in height from the natural bed of the stream or watercourse at the downstream toe of the barrier (or from the lowest elevation of the outside limit of the barrier if it is not across a stream channel or watercourse) to the maximum possible water storage elevation • Has an impounding capacity of 50 acre-feet or more
Dams can be classified according to their purpose, the construction material or methods used, their slope or crosssection, the way they resist the force of the water pressure, or the means used for controlling seepage. Materials used to construct dams include earth, rock, tailings from mining or milling, concrete, masonry, steel, timber, plastic, rubber, and combinations of these.

8.1.2 Causes of Dam Failure
Partial or full failure of dams has the potential to cause massive destruction to the ecosystems and communities located downstream. Partial or full failure can occur as a result of one or a combination of the following reasons (Federal Emergency Management Agency 2016):
• Overtopping caused by floods that exceed the dam capacity (inadequate spillway capacity) • Prolonged periods of rainfall and flooding
• Deliberate acts of sabotage (terrorism)
• Structural failure of materials used in dam construction • Movement and/or failure of the foundation supporting the dam • Settlement and cracking of concrete or embankment dams • Piping and internal erosion of soil in embankment dams • Inadequate or negligent operation, maintenance, and upkeep 179
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• Failure of upstream dams on the same waterway
• Earthquake (liquefaction/landslides).

Many dam failures in the United States have been secondary results of other disasters. The most common causes are earthquakes, landslides, extreme storms, equipment malfunction, structural damage, foundation failures, and sabotage. Poor construction, lack of maintenance and repair, and deficient operational procedures are preventable or correctable by a program of regular inspections. Terrorism and vandalism are serious concerns that all operators of public facilities must plan for; these threats are under continuous review by public safety agencies.

8.1.3 Residual Risk
Dams present a flood risk called “residual risk” that represents flooding that can occur even without a failure at the dam. A storm event that is more severe than the design-storm can result in overtopping, inundation upstream of the dam, or failure of the dam or spillway, potentially resulting in rapid water release (FEMA 2018).

8.1.4 Downstream Hazard Potential Classifications
California’s Division of Safety of Dams has developed a classification system for the downstream hazard potential of state-jurisdiction dams, as shown on Table 8-1. This system is modified from federal guidelines, which recommend three-tier classification. The California system adds a fourth hazard classification of “extremely high.”
Table 8-1. State of California Downstream Hazard Potential Classification Downstream Hazard Potential Classification Potential Downstream Impacts on Life and Property Low No probable loss of human life and low economic and environmental losses.

Losses are expected to be principally limited to the owner’s property.

Significant No probable loss of human life but can cause economic loss, environmental damage, impacts to critical facilities, or other significant impacts.

High Expected to cause loss of at least one human life
Extremely High Expected to cause considerable loss of human life or would result in an inundation area with a population of 1,000 or more.

Source: (California Employment Development Department 2021)

8.1.5 Planning Requirements
465BState of California
All dams whose inundation areas may impact the planning area have emergency action plans (EAPs) on file. The EAPs must include the following (Cal OES 2022):
• Emergency notification flow charts
• Information on a four-step response process
• Description of agencies’ roles and actions in response to an emergency incident • Description of actions to be taken in advance of an emergency • Inundation maps
• Additional information such as revision records and distribution lists. 180

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After the EAPs are approved by the state, the law requires dam owners to send the approved EAPs to relevant stakeholders. Local public agencies can then adopt emergency procedures that incorporate the information in the EAP in a manner that conforms to local needs and includes methods and procedures for alerting and warning the public and other response and preparedness related items (Cal OES 2022):
46BFederal Energy Regulatory Commission
Dams under the jurisdiction of the Federal Energy Regulatory Commission (FERC) also have specified planning requirements. FERC has the largest dam safety program in the United States. It cooperates with many federal and state agencies to ensure and promote dam safety and, more recently, homeland security. FERC requires licensees to prepare emergency action plans and conducts training sessions on how to develop and test these plans. The plans are designed to serve as an early warning system if there is a potential for, or a sudden release of water from, a dam failure or accident to the dam. The plans include operational procedures that may be used, such as reducing reservoir levels and reducing downstream flows and procedures for notifying affected residents and agencies responsible for emergency management. These plans are frequently updated and tested to ensure that in emergency situations everyone knows what to do, thus saving lives and minimizing property damage.

8.1.6 Secondary Hazards
Dam failure can cause severe downstream flooding depending on the magnitude of the failure. Other potential secondary hazards of dam failure include landslides around the reservoir perimeter, bank erosion on the rivers, and destruction of downstream habitat.

8.2 HAZARD PROFILE

8.2.1 Past Events
No dam failures have been recorded in the planning area. However, according to the 2018 State of California Multi-Hazard Mitigation Plan, there have been a small number of dam failures elsewhere in the state in the past 50 years. The most catastrophic event in the state was the failure of the St. Francis Dam in Los Angeles County, which failed in 1928 and killed an estimated 450 people. According to the 2021 Alameda County Local Hazard Mitigation Plan, there have been three failures in the county:
• 1905 Piedmont #1 Dam Failure—An earthen dam built in Oakland in 1903 had an outlet pipe sheared off from its core wall. This was a minor incident; no deaths occurred as a result. • 1918 Calaveras Dam Failure—The San Francisco Public Utilities Commission-owned Calaveras Dam, located in Alameda County, failed during construction in 1918. A landslide damaged the upstream shell of the dam and destroyed the dam’s outlet tower.
• 2015 Rubber Dam 3 Failure—In 2015, the inflatable dam on Alameda Creek (Rubber Dam 3) failed due to vandalism, releasing nearly 50 million gallons of water from the community’s water into the San Francisco Bay. The water was supposed to go into the Niles Cone Groundwater Basin where residents and businesses from the Cities of Newark, Union City and Fremont could access drinking water.

There is a possibility that the planning area experienced the direct or indirect impacts of these events, though no specific information on local impact is available.
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8.2.2 Location
Dams With Potential to Affect Planning Area
According to the California Division of Safety of Dams, as of September 2021, there were 23 dams in Alameda County, of which 18 were classified as high or extremely high hazard. Of these, the Del Valle and Patterson Dams have the potential to impact the planning area if a failure were to occur.

Del Valle Dam
The Del Valle Dam, located outside the planning area in unincorporated Alameda County on Arroyo Del Valle, a tributary of Alameda Creek, was completed in 1968 by the California Department of Water Resources. The dam is outside the planning area, about 5 miles southeast of central Livermore. This earth dam receives stormwater runoff from an area of approximately 150 square miles. The maximum spillway peak discharge is 7,000 cfs.

Construction of the dam created Lake Del Valle, which provides water storage, Alameda Creek flood control, and regulatory storage for a portion of water delivered through the South Bay Aqueduct. The dam is in satisfactory condition as of September 2017, which means it has no recognized safety deficiencies. It is the only flood control dam in the Livermore Valley. The dam has a storage capacity of 77,100 acre-feet of water (California Department of Water Resources 2021b). Table 8-2 provides information on the Del Valle Dam.

Table 8-2. Del Valle Dam Characteristics
Hazard Classa Extremely High
Water Course Arroyo Valle
Owner California Department of Water Resources
Year Built 1968
Dam Type Earth
Crest Length (feet) 880
Height (feet) 222
Storage Capacity (acre-feet) 77,100
Drainage area (sq. mi.) 146
Inundation Area (sq. mi.) 97.98
a. Hazard classification as defined in Table 8-1.

Source: (California Department of Water Resources 2021b) Patterson Dam
The Patterson Dam is listed as high hazard and is owned by the California Department of Water Resources. It was built in 1962 and was constructed as part of the California State Water Project. It is maintained and operated by the California Department of Water Resources. The Project is also operated to improve water quality in the Delta, control Feather River flood waters, provide recreation, and enhance fish and wildlife. Table 8-3 provides information on the Patterson Dam. The dam is outside the planning area, less than a mile east of the eastern city limit of Livermore in unincorporated Alameda County.
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Table 8-3. Patterson Dam Characteristics
Hazard Classa High
Water Course Off stream
Owner California Department of Water Resources
Year Built 1962
Dam Type Earth
Crest Length (feet) 1,275
Height (feet) 39
Storage Capacity (acre-feet) 104
Drainage area (sq. mi.) 0
Inundation Area (sq. mi.) Information not available
a. Hazard classification as defined in Table 8-1.

Source: (California Department of Water Resources 2021b) Mapped Inundation Areas
Dam failure inundation mapping in support of emergency action planning is available for the Del Valle and Patterson dams. The combination of the inundation areas for the two dams was used for the risk assessment of the dam failure hazard in this plan. Figure 8-1 shows the combined inundation area.

8.2.3 Frequency
Dam failures are infrequent and usually coincide with the events that cause them, such as earthquakes, landslides, and excessive rainfall and snowmelt. There is a “residual risk” associated with dams; residual risk is the risk that remains after safeguards have been implemented. The residual risk is associated with events beyond those that the facility was designed to withstand. However, the probability of occurrence of any type of dam failure event is considered to be low in today’s regulatory and dam safety oversight environment.

8.2.4 Severity
The Patterson Dam is rated by the state as a high hazard dam, which means that its failure is likely to result in the loss of at least one life. The Del Valle Dam is rated as extremely high hazard, which means that its failure would likely cause considerable loss of human life or would inundate an area with a population of 1,000 or more. Based on the modeling of the combined inundation areas, dam inundation flood depths can range from shallow (3 feet or less) to deep (10 feet or more).

8.2.5 Warning Time
Warning time for dam failure depends on the cause of the failure. In events of extreme precipitation, evacuations can be planned with sufficient time. In the event of a structural failure due to earthquake, it is possible that there would be no warning time. A dam’s structural type also affects warning time. Earthen dams do not tend to fail completely or instantaneously. Once a breach is initiated, discharging water erodes the breach until either the reservoir water is depleted or the breach resists further erosion. Concrete gravity dams also tend to have a partial breach as one or more monolith sections formed during dam construction are forced apart by the escaping water.

The time for breach formation ranges from a few minutes to a few hours. Alameda County and the Cities of Dublin, Livermore and Pleasanton have established protocols for emergency warning and response through adopted emergency operations plans. These protocols are tied to the emergency action plans created by the dam owners.
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Figure 8-1
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8-7

8.3 EXPOSURE

8.3.1 Population
All populations living in a dam failure inundation zone are exposed to the risk of a dam failure. Figure 8-2 shows the estimated population living in the evaluated inundation area compared to total population for each planning area city. The exposed population represents 16.9 percent of the total planning area population. Population served by DSRSD cannot be mapped to determine its exposure to the dam failure hazard.

Figure 8-2. Population Exposed to Dam Failure and Total City Population, by Jurisdiction

8.3.2 Property
Figure 8-3 summarizes the number and value of planning area buildings within the mapped dam failure inundation zone. Figure 8-4 shows the estimated exposed total value as a percentage of the total replacement value in each city and in the overall planning area. Figure 8-5 shows the distribution by occupancy class of buildings in the inundation area.

8.3.3 Critical Facilities
GIS analysis determined that 299 of the planning area’s 1,161 critical facilities (26 percent) are in the evaluated inundation area. Figure 8-6 shows the distribution of exposed critical facilities by category and jurisdiction.

8.3.4 Environment
The environment would be exposed to a number of risks in the event of dam failure. The inundation could introduce many foreign elements into local waterways. This could result in destruction of downstream habitat and could have detrimental effects on many species of animals, especially endangered species such as salmon. The extent of the vulnerability of the environment is the same as the exposure of the environment. 10 (0.0% of Total)
8,070
(9.4% of Total)
38,988
(50.2% of Total)
72,932
86,149
77,609
0 20,000
40,000
60,000
80,000
100,000
Dublin Livermore Pleasanton
Population
Exposed Population
Total City Population
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Figure 8-3. Number and Exposed Value of Buildings in Dam Failure Inundation Area Figure 8-4. Total Value in Dam Failure Inundation Area as % of Total Replacement Value, by Jurisdiction $2,112,826 $121,708,760
$1,909,255,964
$8,401,758,372
0 $125,021,861
$1,576,456,505
$6,301,326,348
Total Exposed Value
$2,112,826
(2 Buildings)
Total Exposed Value
$246,730,621
(34 Buildings)
Total Exposed Value
$3,485,712,469
(2,914 Buildings)
(12,106 Buildings), Total
Exposed Value,
$14,703,084,720
$0
$4,000,000,000
$8,000,000,000
$12,000,000,000
$16,000,000,000
DSRSD Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value

0.97%

1.2%

11.7%

50.1%

18.2%
0% 20% 40% 60% 80% 100%
DSRSD
Dublin
Livermore
Pleasanton
Planning Area Total
Exposed Value as % of Total City or Area Replacement Value 186

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Figure 8-5. Number of Structures within the Dam Failure Inundation Zone, by Occupancy Class Residential, 2
Residential, 2,643
Residential, 10,941
Commercial, 25
Commercial, 184
Commercial, 876
Industrial, 3
Industrial, 47
Industrial, 129
Agriculture, 0
Agriculture, 0
Agriculture, 0
Religion, 0
Religion, 28
Religion, 22
Government, 4
Government, 9
Government, 14
Education, 0
Education, 3
Education, 124
Dublin
Livermore
Pleasanton
0 2,000 4,000 6,000 8,000 10,000 12,000
Number of Structures in the Inundation Zone
CITIES
Residential, 13,586
Commercial, 1,085
Industrial, 179
Agriculture, 0
Religion, 50
Government, 27
Education, 127
0 5,000 10,000 15,000
Number of Structures in the Inundation Zone

PLANNING AREA TOTAL
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Figure 8-6. Critical Facilities within the Dam Failure Inundation Area, by Jurisdiction

8.4 VULNERABILITY

8.4.1 Population
Displacement and Shelter Requirements
Impacts on population in the planning area were estimated for the evaluated dam failure inundation area.

Estimates for each city and the total planning area are presented in Figure 8-7. Vulnerable populations are all populations downstream from dam failures that are incapable of escaping the area before floodwaters arrive. This population includes the elderly and young who may be unable to get themselves out of the inundation area. The vulnerable population also includes those who would not have adequate warning from a television, radio emergency warning system, siren, cell phone alert or in-person contact.

Communications, 0
Communications, 0
Communications, 10
Communications, 0
Energy, 0
Energy, 0
Energy, 2
Energy, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 22
Food, Water, Shelter, 4
Hazardous Material, 1
Hazardous Material, 7
Hazardous Material, 182
Hazardous Material, 0
Health & Medical, 0
Health & Medical, 0
Health & Medical, 15
Health & Medical, 0
Safety & Security, 1
Safety & Security, 0
Safety & Security, 23
Safety & Security, 0
Transportation, 2
Transportation, 8
Transportation, 22
Transportation, 0
Dublin
Livermore
Pleasanton
DSRSD
0 50 100 150 200 250 300
Number of Critical Facilities in the Flood Zone

PLANNING PARTNERS
Communications, 10
Energy, 2
Food, Water, Shelter, 26
Hazardous Material, 190
Health & Medical, 15
Safety & Security, 24
Transportation, 32
0 50 100 150 200 250 300
Number of Critical Facilities in the Flood Zone

PLANNING AREA TOTAL
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DSRSD does not have any responsibility for sheltering
Figure 8-7. Estimated Persons Displaced or Requiring Short-Term Shelter Due to Dam Failure Vulnerable Populations
Vulnerable populations are all populations downstream from dam failures that are incapable of escaping the area within the allowable time frame. Socially vulnerable populations include the very young, the elderly, and those experiencing poverty. In the cities of Dublin, Livermore, and Pleasanton, socially vulnerable communities specifically include local senior populations (Livermore Senior Center, Dublin Senior Center, and Pleasanton Senior Center), the unhoused, and individuals with disabilities. These socially vulnerable populations are most susceptible based on many factors, including their physical and financial ability to react or respond during a hazard and the ability to be self-sustaining for prolonged periods of time after an incident because of limited ability to stockpile supplies. Socially vulnerable populations may live in areas with substantial population density, inhibiting their ability to escape from the inundation area to safety in enough time. At-risk communities such as those with disabilities or the local senior population may face difficulty evacuating from the senior centers in Dublin, Pleasanton, and Livermore. Vulnerable populations may also lack adequate warning from television, radio emergency warning systems, or alert and warning messages released on social media due to a lack of access to these tools caused by disparities in economic opportunity and socioeconomic status. The potential for loss of life is affected by the capacity and number of evacuation routes available to populations living in areas of potential inundation. DSRSD overlies the City of Dublin and a small portion of the City of Pleasanton. Socially vulnerable population within Dublin would be the same as that for DSRSD. Dublin and DSRSD collaborate on programs for the affected vulnerable populations.

An especially vulnerable population is found among those experiencing homelessness. Not only do those experiencing homelessness face an inequitable lack of access to resources and basic needs, they also face an exceptional risk of injury due to common shelter locations. Those experiencing homelessness often set up shelter under bridges near or along waterways, presenting an exceptional threat to their lives in the event of dam failure and subsequent flooding.
1 3,316
29,373
32,690
0 10,000
20,000
30,000
40,000
Dublin Livermore Pleasanton Total Planning
Area
Number of Displaced Persons
0 225 1,345 1,570
0 10,000
20,000
30,000
40,000
Dublin Livermore Pleasanton Total
Planning
Area
Number of Persons Requiring Short-Term
Shelter
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8.4.2 Property
Vulnerable properties are those closest to the dam failure inundation area. These properties would experience the largest, most destructive surge of water. Low-lying areas are also vulnerable since they are where the dam waters would collect. It is estimated that there could be up to $5.0 billion of loss from a dam failure affecting the planning area. This represents 27.0 percent of the total exposure within the inundation area, or 6.3 percent of the total assessed value of the planning area. Figure 8-8 summarizes the loss estimates for dam failure by damage type and jurisdiction. The estimated number of buildings that would be impacted is shown in Figure 8-9. The risk assessment also estimated the amount of debris that would be generated by a dam failure in the planning area, as summarized in Figure 8-10.

8.4.3 Critical Facilities
Hazus estimated damage to critical facilities in the dam failure inundation zones as shown in Figure 8-11. Typical vulnerabilities of affected critical facilities include the following:
• Transportation routes are vulnerable to dam inundation and have the potential to be wiped out, creating isolation issues and significant disruption to travel. Those that are most vulnerable are those that are already in poor condition and would not be able to withstand a large water surge. • Utilities such as overhead power lines, cable, and phone lines in the inundation zone could be vulnerable.

If phone lines were lost, significant communication issues may occur in the planning area due to limited cell phone reception in many areas.
• Emergency response would be hindered due to the loss of transportation routes the inundation zone. • Some protective-function facilities in the safety and security category located in the inundation zone could be lost.
• Recovery time to restore many critical functions after an event may be lengthy.

8.4.4 Environment
The environment would be vulnerable to a number of risks in the event of dam failure. The inundation could introduce foreign elements into local waterways, resulting in destruction of downstream habitat and detrimental effects on many species of animals, especially endangered species. The extent of the vulnerability of the environment is the same as the exposure of the environment.

8.5 FUTURE TRENDS IN DEVELOPMENT
All land use decision-making is guided by the goals, policies and implementation measures contained in the land use elements of Dublin, Livermore and Pleasanton’s general plans. The Dublin general plan’s seismic safety element, Livermore general plan’s public safety element, and Pleasanton’s general plan’s public safety element establish standards and plans for protecting the community from hazards. Most of the areas vulnerable to the worst impacts from a dam failure correspond to the flood hazard areas. Flood-related policies in the general plans will help to reduce the risk associated with the dam failure hazard for all future development in the planning area. 190

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Figure 8-8. Loss Estimates for Dam Failure
Figure 8-9. Number of Buildings Impacted by Dam
Failure
Figure 8-10. Estimated Structural Debris Generated by
Dam Failure
$8,451,304 $3,449,495
$214,302,814
$2,187,729,694
0 $9,452,187
$122,324,740
$2,450,433,806
Total Loss
$8,451,304
(0.1% of Total Value)
Total Loss
$12,901,682
(1.1% of Total Value)
Total Loss
$336,627,554
(15.8% of Total Value)
$0
$500,000,000
$1,000,000,000
$1,500,000,000
$2,000,000,000
$2,500,000,000
$3,000,000,000
DSRSD Dublin Livermore Pleasanton
Estimated Loss
Building Loss
Contents Loss
4 25
1,195
11,170
12,394
0 2000
4000
6000
8000
10000
12000
14000
DSRSD
Dublin
Livermore
Pleasanton
Total Planning
Area
Number of Buildings Impacted by Dam Failure
0 448
31,422
263,824
295,794
0 50000
100000
150000
200000
250000
300000
350000
DSRSD
Dublin
Livermore
Pleasanton
Total Planning
Area
Debris Generated by Dam Failoure (tons)
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Figure 8-11. Estimated Damage to Critical Facilities from Dam Failure

8.6 SCENARIO
An earthquake within the region could lead to liquefaction of soils around the dams. This could occur without warning during any time of the day. A human-caused failure such as a terrorist attack also could trigger a catastrophic failure of a dam that impacts the planning area. The worst-case scenario for the dam failure hazard would be a full failure of the Del Valle Dam. Such a failure would result in a large portion of Pleasanton being inundated and a smaller portion of Dublin and Livermore. Critical facilities located in the dam inundation area would likely experience failure, resulting in a severe disruption of essential services.

8.7 ISSUES
The most significant issue associated with dam failure involves the properties and populations in the inundation zones. Flooding as a result of a dam failure would significantly impact these areas. There is often limited warning time for dam failure. These events are frequently associated with other natural hazard events such as earthquakes, landslides or severe weather, which limits their predictability and compounds the hazard. Other important issues associated with dam failure include the following:
• Federally regulated dams have an adequate level of oversight and sophistication in the development of emergency action plans for public notification in the unlikely event of failure. However, the protocol for notification of downstream citizens of imminent failure needs to be tied to local emergency response planning. 0.0

0.0 16.9

28.0 12.0

15.6 0.00.01.3

45.7 44.1

43.3 64.6

0.0 0 0
23 192
15 17
88 0
40 80
120
160
200
0 20
40 60
80 100
Communications Energy Food, Water,
Shelter
Hazardous
Materials
Health/Medical Safety/Security Transportation
Number of Facilities Affected
Average Damage as % of Total Value
% Damage to Structure % Damage to Contents Number of Facilities Affected 192

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8-15
• Mapping for federally regulated dams is already required and available; however, mapping that estimates inundation depths is needed for dams that are not federally regulated, in order to better assess the risk associated with failure of these facilities.
• Most dam failure mapping required at federal levels requires determination of the probable maximum flood. While the probable maximum flood represents a worst-case scenario, it is generally the event with the lowest probability of occurrence. For dams that are not federally regulated, mapping of failure scenarios that are less extreme than the probable maximum flood but have a higher probability of occurrence can be valuable to downstream community officials and emergency managers. This type of mapping can illustrate areas potentially impacted by more frequent events to support emergency response and preparedness actions.
• The concept of residual risk associated with structural flood control projects should be considered in the design of capital projects and the application of land use regulations. • Addressing security concerns and the need to inform the public of the risk associated with dam failure is a challenge for public officials.
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9. DROUGHT

9.1 GENERAL BACKGROUND
Drought is a significant decrease in water supply relative to what is needed to sufficiently meet typical demand in each location. It is a normal phase in the Mediterranean climate cycle, originating from a deficiency of precipitation over an extended period, usually a season or more. This leads to a water shortage for some activity, group, or environmental sector. Drought is generally defined based on five ways of measuring it (National Drought Mitigation Center 2022a):
• Meteorological drought—Based on measurements such as precipitation deficit compared to normal or expected precipitation. Anomalies of precipitation and temperature may last from several months to several decades. How long they last depend on interactions between the atmosphere and the oceans, soil moisture and land surface processes, topography, internal dynamics, and the accumulated influence of global weather systems.
• Agricultural drought—Based on impacts due to reduced precipitation and water supply (e.g., crop loss, herd culling, etc.)
• Hydrological drought—Based on measurements of stream flows, groundwater, and reservoir levels relative to normal conditions
• Socioeconomic drought—Based on direct and indirect socio-economic impacts on society and the economy. Socioeconomic drought occurs when the demand for an economic good exceeds supply as a result of a weather-related shortfall in water supply. If a community has stored enough water to meet its needs in the event of a shortage of rainfall, then it may not experience socioeconomic drought even though its geographic area experiences meteorological drought. • Ecological drought—Defined as a prolonged and widespread deficit in naturally available water supplies, including changes in natural and managed hydrology, that create multiple stresses across ecosystems.

9.1.1 Monitoring and Categorizing Drought
National Oceanic and Atmospheric Administration Drought Indices The National Oceanic and Atmospheric Administration (NOAA) has developed several indices to measure the impacts and severity of meteorological, agricultural, and hydrological drought and to map their extent and locations:
• The Crop Moisture Index measures short-term drought weekly to assess impacts on agriculture. • The Palmer Z Index measures short-term drought on a monthly scale. 195
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• The Palmer Drought Severity Index is based on long-term weather patterns. The intensity of drought in a given month is dependent on current weather plus the cumulative patterns of previous months. Weather patterns can change quickly, and the Palmer Drought Severity Index can respond fairly rapidly. • The Palmer Hydrological Drought Index quantifies hydrological effects (reservoir levels, groundwater levels, etc.), which take longer to develop and last longer. This index responds more slowly to changing conditions than the Palmer Drought Index.
• The Standardized Precipitation Index considers only precipitation. A value of zero indicates the median precipitation amount; the index is negative for drought and positive for wet conditions. The Standardized Precipitation Index is computed for time scales ranging from one month to 24 months.

Each of these indices is meaningful for different sectors of society and the economy. For example, an urbanized areas that uses water from reservoirs would be sensitive to hydrological drought characterized by the Palmer Hydrological Drought Index, while unirrigated grazing land would be sensitive to meteorological drought characterized by the Crop Moisture Index. Maps of these indices show drought conditions nationwide at a given point in time. They are not necessarily indicators of any given area’s long-term susceptibility to drought. Recent examples of these maps are shown on Figure 9-1.

U.S. Drought Monitor
The U.S. Drought Monitor (USDM) is a map that is updated weekly to show the location and intensity of drought across the country. The USDM uses a five-category system (U.S. Drought Monitor 2022):
• D0—Abnormally Dry
➢ Short-term dryness slowing planting, growth of crops
➢ Some lingering water deficits
➢ Pastures or crops not fully recovered
• D1—Moderate Drought
➢ Some damage to crops, pastures
➢ Some water shortages developing
➢ Voluntary water-use restrictions requested
• D2—Severe Drought
➢ Crop or pasture loss likely
➢ Water shortages common
➢ Water restrictions imposed
• D3—Extreme Drought
➢ Major crop/pasture losses
➢ Widespread water shortages or restrictions
• D4—Exceptional Drought
➢ Exceptional and widespread crop/pasture losses
➢ Shortages of water creating water emergencies
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Sources: National Weather Service, 2022; National Centers for Environmental Information, 2022 Crop Moisture Index (Week Ending April 23, 2022)
Palmer Z Index Short-Term Drought Conditions (March 2022) Palmer Modified Index (March 2022)
Palmer Hydrological Drought Index (March 2022)
Standardized Precipitation Index (24-Months Ending April 2022) Figure 9-1. Standard National Drought and Precipitation Indices 197
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The USDM categories show experts’ assessments of conditions related to drought. These experts check variables including temperature, soil moisture, stream flow, water levels in reservoirs and lakes, snow cover, and meltwater runoff. They also check whether areas are showing drought impacts such as water shortages and business interruptions. Associated statistics show what proportion of various geographic areas are in each category of dryness or drought, and how many people are affected. U.S. Drought Monitor data go back to 2000.

9.1.2 Drought Impacts
Drought can have a widespread impact on the environment and the economy, although it typically does not result in loss of life or damage to structures, as do other natural disasters. The National Drought Mitigation Center uses three categories to describe likely drought impacts:
• Economic Impacts—These impacts of drought cost people (or businesses) money. Farmers’ crops are destroyed; low water supply necessitates spending on irrigation system modifications, drilling of new wells, and/or trucking in water; water-related businesses (such as sales of boats and fishing equipment) may experience reduced revenue.
• Environmental Impacts—Plants and animals depend on water. When a drought occurs, their food supply can shrink, and their habitat can be damaged.
• Social Impacts—Social impacts include public safety, health, conflicts between people when there is not enough water to go around, and changes in lifestyle.

The demand that society places on water systems and supplies—such as expanding populations, irrigation, and environmental needs—contributes to drought impacts. Drought can lead to difficult decisions regarding the allocation of water, as well as stringent water use restrictions, water quality problems, and inadequate water supplies for fire suppression. There are also issues such as growing conflicts between agricultural uses of surface water and in-stream uses, surface water and groundwater interrelationships, and the effects of growing water demand on uses of water.

Vulnerability of an activity to drought depends on its water demand and the water supplies available to meet the demand. The impacts of drought vary between sectors of the community in both timing and severity:
• Water supply—The water supply sector encompasses urban and rural drinking water systems that are affected when a drought depletes surface and groundwater supplies due to reduced runoff and recharge from precipitation.
• Agriculture and commerce—Impacts on agriculture and associated commerce include the reduction of crop yield and livestock sizes due to insufficient water supply for crop irrigation and maintenance of ground cover for grazing.
• Environment, public health, and safety—Impacts on the environmental, public health, and safety sectors include wildfires that are both detrimental to the forest ecosystem and hazardous to the public.

The impacts also includes the desiccation of streams, resulting in the reduction of in-stream habitats for native species.

9.1.3 California Drought Response
During critically dry years, the California State Water Resources Control Board can mandate conservation by water users and agencies to address statewide water shortages. Table 9-1 lists State Drought Management Program stages mandated to water right holders.
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Table 9-1. State Drought Management Program
Drought Stage State Mandated Customer Demand Reduction Rate Impacts Stage 0 or 1 <10% Normal rates
Stage 2 10 to 15% Normal rates; Drought surcharge
Stage 3 15 to 20% Normal rates; Drought surcharge
Stage 4 >20% Normal rates, Drought surcharge

9.1.4 Secondary Hazards
The secondary impact most commonly associated with drought is wildfire. A prolonged lack of precipitation dries out vegetation, which becomes increasingly susceptible to ignition as the duration of the drought extends. In addition, lack of sufficient water resources can stress trees and other vegetation, making them more vulnerable to infestation from pests, which in turn, can make them more vulnerable to ignition. Prolonged droughts can impact underground aquifers, thus impacting groundwater supplies. Algae blooms can occur in surface water reservoirs that are stressed by drought impacts.

9.2 HAZARD PROFILE

9.2.1 Local Water Supply
Water Supply System
The Zone 7 Water Agency (Zone 7), a water wholesaler, provides treated drinking water to four major retailers in the planning area that serve approximately 240,000 people and businesses. Figure 9-2 summarizes the quantities of water managed by Zone 7. The wholesale water has three sources: South Bay Aqueduct that originates from the California State Water Project; Lake Del Valle storage reservoir that is approximately 10 miles from Livermore; and groundwater from local wells (Zone 7 Water Agency 2020).

The following retail water purveyors in the Tri-Valley planning purchase water from Zone 7:
• Dublin San Ramon Services District—Dublin San Ramon Services District is a public agency that distributes water and recycled water, and collects, treats and disposes of wastewater for 193,400 people in Dublin, southern San Ramon, Dougherty Valley, and Pleasanton. It provides water services only to Dougherty Valley and the City of Dublin (Dublin San Ramon Services District 2021). • City of Livermore—Livermore Municipal Water purchases potable water from Zone 7 Water agency and provides water to more than 28,000 Livermore residents in addition to significant industrial and commercial areas. The balance of residents are served by the California Water Service Company, or Cal Water (City of Livermore n.d.).
• City of Pleasanton—The City of Pleasanton Utilities Division provides potable water to Pleasanton residents and businesses. The City purchases approximately 80 percent of the water from the Zone 7 Water Agency; the remaining 20 percent comes from local groundwater pumped from City-owned and operated wells (City of Pleasanton 2020).
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Source: (Zone 7 Water Agency 2020)
Figure 9-2. Zone 7 Water Agency Supply and Use, Fiscal Year 2019-2020 Water Supply Strategy
Zone 7 includes a water supply strategy in its 2020 Urban Water Management Plan to meet its planning objectives for water supply reliability, cost, water quality, environmental protection and risk. It evaluates a range of water supply and water conservation options and recommended a strategy that includes desalination, recycled water, conservation, groundwater management and off-site banking/transfers.

Zone 7 has projected water supply and demand through 2045 for normal-year, single-dry-year, and multiple-dryyear conditions. Table 9-2 shows that under normal hydrologic conditions, Zone 7’s supplies are adequate to meet projected demand through 2045. Surplus supplies are stored as carryover, used to recharge the Main Basin, and stored in the Kern County groundwater banks. The supplies shown below in the table are representative of expected normal conditions or normal operational targets (Zone 7 Water Agency 2021). 200

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Table 9-2. Projected Normal Year Water Supply and Demand Comparison Projections (by year) (acre-feet per year)
Supply/Demand 2025 2030 2035 2040 2045 (opt)
Supply Component
State Water Project Table A 47,000 46,000 45,000 43,500 43,50 Yuba Accord 0 0 0 0 0
Turnback Pool 0 0 0 0 0
State Water Project - Carryover 10,000 10,000 10,000 10,000 10,000 Arroyo Valle 5,500 5,500 5,500 5,500 5,500
Main Basin 9,200 9,200 9,200 9,200 9,200
Semitropic 0 0 0 0 0
Cawelo 0 0 0 0 0
BARDP/Potable Reuse 0 5,000 5,000 5,000 5,000
Sites Reservoir Project 0 10,000 10,000 10,000 10,000
Transfers 5,000 5,000 0 0 0
Chain of Lakes 0 0 0 0 0
TOTAL SUPPLY 76,700 90,700 84,700 83,200 83,200
Demand Component
Retail Demand 43,000 43,200 43,400 43,700 43,700
Untreated Water Demand 5,500 7,800 8,300 8,300 8,300
Direct Retail Demand 800 800 800 800 800
Losses 1,000 1,000 1,300 2,500 2,500
TOTAL DEMAND 50,300 52,800 53,800 55,300 55,300
Supply & Demand Comparison
Supply Totals 76,700 90,700 84,700 83,200 83,200
Demand Totals 50,300 52,800 53,800 55,300 55,300
Difference 26,400 37,900 30,900 27,900 27,900
Source: (Zone 7 Water Agency 2021)
Zone 7 Water Management Plan
Zone 7’s 2020 Urban Water Management Plan was developed to address a water supply shortage up to 50 percent. Zone 7 has sufficient supply to meet demand in most years, but shortages can occur as a result of dry weather or an extended interruption of imported supplies. Voluntary water restrictions may also be initiated by an executive order from the governor due to state-level water conditions. Table 9-3 shows the six water shortage stages, which align with the State’s standard stages (Zone 7 Water Agency 2021). Since Zone 7 is a wholesale water agency, it has not adopted ordinances that set or enforce consumption limits at the customer level.

Local Retail Water Purveyors
Local retail water purveyors in the Tri-Valley planning area (Dublin San Ramon Services District, Livermore Municipal Water, California Water Service Company, and City of Pleasanton Utilities Division) have prepared for water supply interruptions with water shortage contingency plans. The plans consist of four stages of water conservation and give guidelines to residential and commercial users’ conservation action ideas. These plans also include per capita allotment, penalties and customer incentives for conservation. 201
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Table 9-3. Water Shortage Contingency Plan Levels
Shortage
Level
Percent Shortage
Range Water Shortage Condition Shortage Response Actions 1 Up to 10%
• Agency has adequate supply and seeks to preserve water resources for the future; or
• Assessment shows that water supply is not able to meet normal demands by up to 10%; or
• Definable event has reduced water supply by up to 10%. • Public outreach to support
voluntary conservation.
• Ask retailers for voluntary
demand reduction, as needed.
2 Up to 20%
• Assessment leads to a reasonable conclusion that water supplies may not adequately meet normal demands in the current or upcoming years; or
• Assessment shows that water supply is not able to meet normal demands by up to 20%; or
• Definable event has reduced water supply by up to 20%. • Expand public outreach to
support conservation.
• Ask retailers for voluntary or
mandatory demand reduction,
as needed. Only the latter will
be enforced.
3 Up to 30%
• Previous water conservation target has not been met; or • Assessment shows that water supply is not able to meet normal demands by up to 30%; or
• Definable event has reduced water supply by up to 30%. • Intensify public outreach to
support conservation.
• Ask retailers for mandatory
demand reduction.
4 Up to 40%
• Previous water conservation target has not been met; or • Assessment shows that water supply is not able to meet normal demands by up to 40%; or
• Definable event has reduced water supply by up to 40%. • Intensify public outreach to
support conservation.
• Ask retailers for mandatory
demand reduction.
5 Up to 50%
• Previous water conservation target has not been met; or • Assessment shows that water supply is not able to meet normal demands by up to 50%; or
• Definable event has reduced water supply by up to 50%. • Intensify public outreach to
support conservation.
• Ask retailers for mandatory
demand reduction.
6 >50%
• Previous water conservation target has not been met; or • Assessment shows that water supply is not able to meet normal demands by more than 50%; or
• Definable event has reduced water supply by more than 50%. • Intensify public outreach to
support conservation.
• Ask retailers for mandatory
demand reduction.

Source: (Zone 7 Water Agency 2021)

9.2.2 Past Events
In California, droughts typically occur after two or three years of below-average rainfall for the period from November to March, when about 75 percent of the State’s average annual precipitation falls. December, January, and February are when approximately 50 percent of the rainfall occurs in California.

Drought has affected nearly every county in California at one time, causing more than $5.1 billion in damage.

They are a cyclic part of the climate of the State and occur at any time of the year, with an average recurrence interval in Alameda County at least every decade (Cal OES 2018) (Alameda County 2021). This section provides information regarding drought events that occurred in California and Alameda County. 202

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State of California
State Records
The California Department of Water Resources has state hydrologic data back to the early 1900s. The hydrologic data show multi-year droughts from 1912 to 1913, 1918 to 1920 and 1922 to 1924, and 1928 to 1934 (Department of Water Resources 2022). Since then, five prolonged periods of drought occurred in California:
• 2020 to Present Drought— At the time of this plan update, California was in its third year of another multi-year drought. By July of 2021, a state of emergency had been declared in 50 counties, including Alameda County, and the governor appealed to residents to collectively reduce water usage by 15 percent that year. A few months later the governor authorized the State Water Board to ban wasteful water uses, and made plans to invest $5.2 billion over the next three years in drought response and water resilience efforts, seeing this drought as the worst in over a century. The first few months of 2022 were especially remarkable in terms of weather conditions, being the driest January, February, and March on record in California (California Drought Action 2022).
• 2012 to 2017 Drought—California’s drought has set several records for the state. The period from 2012 to 2014 ranked as the driest three consecutive years for statewide precipitation. Calendar year 2014 set new climate records for statewide average temperatures and for record-low water allocations from State Water Project and federal Central Valley Project contractors. Calendar year 2013 set minimum annual precipitation records for many communities. The state has detailed executive orders and regulations concerning water conservation and management. Total impacts of the drought cannot be determined until after its conclusion. Based on a wet winter, Governor Brown declared an end to the drought emergency on April 7, 2017, in Executive Order B-40-17, except in four counties (Fresno, Kings Tulare, and Tuolumne) (California Water Boards 2017).
• 2007 to 2009 Drought—The Governor issued an Executive Order that proclaimed a statewide drought emergency on June 4, 2008, after spring 2008 was the driest spring on record and low snowmelt runoff.

On February 27, 2009, the Governor proclaimed a state of emergency for the entire state as the severe drought conditions continued widespread impacts and the largest court-ordered water restriction in state history (at the time).
• 1987 to 1992 Drought —California received precipitation well below average levels for four consecutive years. While the Central Coast was most affected, the Sierra Nevadas in Northern California and the Central Valley counties were also affected. During this drought, only 56 percent of average runoff for the Sacramento Valley was received, totaling just 10 million acre-feet. In 1991, the State Water Project sharply decreased deliveries to water suppliers including the San Francisco Bay Area. By February 1991, all 58 counties in California were suffering from drought conditions, and urban areas as well as rural and agricultural areas were impacted.
• 1976 to 1977 Drought—California had one of its most severe droughts due to lack of rainfall during the winters of 1976 and 1977. 1977 was the driest period on record in California, with the previous winter recorded as the fourth driest in California’s hydrological history. The cumulative impact led to widespread water shortages and severe water conservation measures throughout the state. Only 37 percent of the average Sacramento Valley runoff was received, with just 6.6 million acre-feet recorded. Over $2.6 billion in crop damage was recorded in 31 counties. Alameda County was included in FEMA-3023- EM-CA declaration on January 20, 1977.

Figure 9-3 shows the history of statewide drought since 2000. 203
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California | Drought.gov
Figure 9-3. Records of Statewide Drought in California Since 2000 FEMA Drought Declarations
Between 1954 and 2021, the State of California experienced one FEMA-declared major disaster (DR) or emergency (EM) classified as a drought: Declaration EM-3023, a drought emergency issued in 1977 and applying to all California counties, including Alameda County (FEMA 2022).

Alameda County
County Drought Records
The following drought events impacted Alameda County:
• 2020 to Present—This is an ongoing event with state of emergency declarations in 50 counties, including Alameda County.
• 2007 to 2009—This event affected the entire state, particularly the central coast. It was a three year drought due to below average rainfall, low snowmelt runoff, and the largest court ordered water restriction in state history. The dry conditions damaged crops, deteriorated water quality, and caused extreme fire danger. California proclaimed a state disaster in 2008 and 2009. Damages included $300 million in agricultural revenue loss and potential $3 billion in economic losses over time. • 1987 to 1992—This event affected the entire state.
• 1976 to 1977—This event affected the entire state with the exception of southwestern deserts. These were the two driest years in California’s history. The drought was most severe in the northern two-thirds of the State. California proclaimed a statewide disaster that did not include Alameda County, but the federal disaster declaration in 1977 did include Alameda County. Damage totaled $2.664 billion ($888.5 million in 1976 and $1.775 billion in 1977).
• 1959 to 1962—This event affected the entire state.
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• 1943 to 1951—This event affected the entire state.
• 1928 to 1937—This event affected the entire state.
• 1922 to 1926—This event affected the entire state with the exception of central Sierra Nevada. • 1917 to 1921—This event affected the entire state with the exception of central Sierra Nevada and the north coast.

U.S. Department of Agriculture Drought Declarations
Agriculture-related disasters and disaster declarations are common in the United States. The U.S. Department of Agriculture (USDA) Farm Service Agency provides assistance for natural disaster losses resulting from drought, flood, fire, freeze, tornadoes, pest infestation, and other natural disasters. The Secretary of Agriculture is authorized to designate counties as disaster areas to make emergency loans to producers suffering losses. Between 2012 and June 2022, Alameda County and Contra Costa County were included in 16 and 15 drought-related USDA disaster declarations, respectively (USDA 2022):
• S5146 in 2022
• S4916 in 2021
• S4697 in 2020
• S4144 and S4163 in 2017
• S3952 in 2016
• S3784 and S3943 (not Contra Costa) in 2015
• S3626, S3637, S3743, and 3797 (not Alameda) in 2014
• S3547 (not Contra Costa), S3558 and S3569 in 2013
• S3248 and S3379 in 2012.

Local Impacts of the Ongoing (2020-Present) Drought
The Cities of Dublin, Livermore, and Pleasanton all initiated water shortage contingency plans during the most recent drought. Each city carried out public education campaigns about water conservation and took steps to conserve water. Zone 7 and its retailers maintain a website for Tri-Valley residents with information on waterwise gardening www.trivalleywaterwise.com (Water-Wise Gardening Tri-Valley 2022). The following sections describe examples of how local proprietors dealt with drought.

Zone 7
At the beginning of September of 2021, the Zone 7 Board of Directors unanimously agreed at a special meeting to declare a Drought Emergency and a Stage 2 Water Shortage Emergency. Included in this declaration was a 15 percent water conservation mandate for all its retailers, which had been preceded by a voluntary 10 percent conservation goal earlier in the year. Zone 7 declared a local drought emergency in order to accelerate the construction of projects that will improve the dependability of its water supply. This includes the Valley Pump Station, which had been scheduled to be completed in the summer of 2023 but was moved up to be finished in the summer of 2022 (Zone 7 Water Agency 2021).
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Dublin San Ramon Services District and City of Dublin
In September 2021, the Dublin San Ramon Services District, which provides water service to Dublin and parts of the neighboring town of San Ramon, declared a Stage 2 Water Shortage Emergency. This included restrictions on the use of water for landscaping and irrigation, washing homes and vehicles, construction work, and other activities. The District also carried out public outreach and education campaigns about water conservation. (Dublin San Ramon Services District 2021).

City of Livermore
The City of Livermore City Council declared a Stage 2 Water Shortage Emergency in September 2021, establishing limitations on the use of water for landscaping and irrigation, washing homes and vehicles, and construction work (City of Livermore n.d.). The City of Livermore Water Shortage Contingency Plan, last updated in 2020 includes water conservation strategies in response to shortages.

In February 2022, 1 percent less water was consumed in Livermore compared to February 2020 (City of Livermore n.d.). In September 2021, the City Council set a water conservation goal of 15 percent less water consumption than 2020, and that conservation record was exceeded. In December 2021, Livermore used 22 percent less water than in December 2020.

City of Pleasanton
The City of Pleasanton declared a local drought emergency and Stage 2 Water Shortage in October 2021, aiming for a 15 percent reduction in water usage compared to 2020 and using many of the same measures as other communities and agencies (limitations on water use for landscaping, construction activities, etc.) (City of Pleasanton n.d.).

9.2.3 Location
If a drought is occurring in Alameda County or neighboring Contra Costa County, then the planning area is most likely being impacted as well. The entire planning area is susceptible to droughts and impacts brought on by such events. Figure 9-4 illustrates the drought in January 2023; source NCEI -NOAA. The planning area is outlined in a black circle near the Bay Area in a black circle. Figure 9-5 illustrates drought conditions in the planning area (outlined in a black ring) in June 2023.

9.2.4 Frequency
Drought has a high probability in the planning area:
• From January 2000 through March 2023, the USDM rating was D1 or higher during 550 weeks in some part of Alameda County and 545 weeks in some part of Contra Costa County, out of 1,213 weeks— roughly one out of every two weeks (see Figure 9-6).
• Alameda and Contra Costa Counties were included in U.S. Department of Agriculture (USDA) drought disaster declarations in nine of the past 11 years (USDA, 2022). • The planning area has experienced three significant multi-year droughts in the last 40 years (1982 to 2022), amounting to a severe multi-year drought every six to seven years on average. 206

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The black circle identifies the planning area
Figure 9-4. Palmer Drought Severity Index, January 2023 Source: U.S. Drought Monitor (https://droughtmonitor.unl.edu/Maps/MapViewer.aspx).

The black circle identifies the planning area
Figure 9-5. U.S. Drought Monitor Map of Planning Area Drought Conditions, June 2023 207
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Figure 9-6. Percent of Alameda and Contra Cosa Counties Affected by Each USDM Rating, 2000 – 2023

9.2.5 Severity
The severity of any given drought depends on the degree of moisture deficiency, the duration, and the size and location of the affected area. The longer the duration of the drought and the larger the area impacted, the more severe the potential impacts.

U.S. Drought Monitor Ratings
Alameda County has a history of severe droughts. As shown in Figure 9-6, at least part of the county has experienced extreme (D3) or exceptional (D4) droughts more than once since 2000.

Drought Impact Reporter
The National Drought Mitigation Center (NDMC) developed the Drought Impact Reporter in response to the need for a national drought impact database for the United States. Information comes from a variety of sources: on-line, drought-related news stories and scientific publications, members of the public who visit the website and submit a drought-related impact for their region, members of the media, and members of relevant government agencies.

The database is being populated beginning with the most recent impacts and working backward in time.

The Drought Impact Reporter contains information on 201 impacts from droughts that specifically affected Alameda County from 2006 through May 5, 2022 (National Drought Mitigation Center 2022). The following are the categories and reported number of impacts (some impacts are assigned to more than one category):
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• Agriculture—45
• Business and Industry—12
• Energy—6
• Fire—19
• Plants and Wildlife—40
• Relief, Response, and Restrictions—128
• Society and Public Health—69
• Tourism and Recreation—9
• Water Supply and Quality—138

9.2.6 Warning Time
Predicting drought depends on the ability to forecast precipitation and temperature. Only generalized warning can take place due to the numerous variables that scientists have not pieced together well enough to make accurate and precise predictions.

Determination of when drought begins is based on impacts on water users and assessments of available water supply, including water stored in reservoirs or groundwater basins. Different water agencies have different criteria for defining drought. Some issue drought watch or drought warning announcements.

9.3 EXPOSURE
All people, property and environments within the planning area would be exposed to some degree to the impacts of moderate to extreme drought conditions.

9.4 VULNERABILITY

9.4.1 Population
The entire population of the planning area is vulnerable to drought events. Drought conditions can affect people’s health and safety, including health problems related to low water flows and poor water quality, and health problems related to dust. Droughts can also lead to the loss of human life (National Centers for Environmental Information 2021). Other possible impacts include recreational risks; effects on air quality; diminished living conditions related to energy, air quality, and hygiene; compromised food and nutrition; and increased incidence of illness and disease (Centers for Disease Control and Prevention 2020).

The local at-risk senior population in the Tri-Valley planning area may be greatly affected by these potential impacts in Dublin, Livermore, Pleasanton, and areas served by DSRSD, especially in the event of water-borne pathogens entering the local water supply. Drought conditions causing shortages of water for human consumption may amplify these effects on local at-risk communities, such as seniors and homeless persons, among others.

While seniors may be readily identified because of participation at senior centers, the homeless population can be transient. Local law enforcement (Livermore Police, Pleasanton Police, and in Dublin Alameda County Sheriff) are sometime familiar with places where the homeless population congregates. These law enforcement agencies patrol these areas in the normal course of their routines and interact with them as necessitated. 209
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Droughts can also lead to reduced local firefighting capabilities. Vulnerable populations who rely on rainfall catchment for residential water supply may be especially impacted if they do not have the physical or financial ability to obtain imported water to refill dry catchment tanks. How and to what degree drought affects the planning area’s vulnerable populations does vary depending on scope and severity.

Alameda County, the Cities of Dublin, Livermore and Pleasanton, regional water purveyors, and other regional stakeholders have spent considerable effort to protect life, safety, and health during times of consecutive dry years, such as the current drought. Provisions and measures have been taken to analyze and account for anticipated water shortages. With the actions implemented by the Cities of Dublin, Livermore and Pleasanton and the coordination with Alameda County, the planning area has the ability to minimize and reduce impacts on residents and water consumers in the planning area. No significant life or health impacts as a result of drought are anticipated in the planning area.

9.4.2 Property
No structures will be directly affected by drought conditions, though some structures may become vulnerable to wildfires, which are more likely following years of drought. Droughts can have significant impacts on other types of property such as landscaped areas and economically important natural resources. Drought causes the most significant economic impacts on industries that use water or depend on water for their business, most notably agriculture and related sectors (forestry, fisheries, and waterborne activities), power plants, and oil refineries. In addition to losses in yields in crop and livestock production, drought is associated with increased insect infestations, plant diseases, and wind erosion.

Drought can lead to other losses because so many sectors are affected—losses that include reduced income for farmers and reduced business for retailers and others who provide goods and services to farmers. This leads to unemployment, increased credit risk for financial institutions, capital shortfalls, and loss of tax revenue. Prices for food, energy, and other products may also increase as supplies decrease.

9.4.3 Critical Facilities
Critical facilities as defined for this plan will continue to be operational during a drought. Critical facility features such as landscaping may not be maintained due to limited water resources, but the risk to critical facility core functions is low.

9.4.4 Environment
Groundwater and Streams
Drought generally does not affect groundwater sources as quickly as surface water supplies, but groundwater supplies generally take longer to recover. Reduced precipitation during a drought means that groundwater supplies are not replenished at a normal rate. This can lead to a reduction in groundwater levels and problems such as reduced pumping capacity or wells going dry. Shallow wells are more susceptible than deep wells.

Reduced replenishment of groundwater affects streams, especially during the summer when there is little or no precipitation. Reduced groundwater levels mean that even less water will enter streams when stream flows are lowest. Where stream flows are reduced, development that relies on surface water may seek to establish new groundwater wells, which could further increase groundwater depletion. 210

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Other Potential Losses
Environmental losses from drought are associated with damage to plants, animals, wildlife habitat, and air and water quality; forest and range fires; degradation of landscape quality; loss of biodiversity; and soil erosion.

Wildlife habitat may be degraded through the loss of wetlands, lakes, and vegetation. The degradation of landscape quality, including increased soil erosion, may lead to a more permanent loss of biological productivity.

Drying up or dying off of forests could reduce ecological values.

Some of these effects are short-term and conditions quickly return to normal following the end of the drought.

Other environmental effects linger for some time or may even become permanent. Although environmental losses are difficult to quantify, growing public awareness and concern for environmental quality has forced public officials to focus greater attention and resources on these effects.

9.5 FUTURE TRENDS IN DEVELOPMENT
Land use planning is directed by general plans adopted under California’s General Planning Law. Municipal planning partners are encouraged to establish general plans with policies directing land use and dealing with issues of water supply and the protection of water resources. These plans provide the capability at the local municipal level to protect future development from the impacts of drought. Dublin, Livermore and Pleasanton reviewed their general plans under the capability assessments performed for this effort. Deficiencies identified by these reviews can be identified as mitigation actions to increase the capability to deal with future trends in development.

9.6 SCENARIO
Continuation or exacerbation of the current drought across California—an extreme, multiyear drought with record-breaking rates of low precipitation and high temperatures—is the worst-case scenario for the planning area. Low precipitation and high temperatures intensify the possibility of wildfires throughout the planning area, increasing the need for water, when water is already in limited supply. Surrounding regions, also in drought conditions, could increase their demand for the water supplies also relied upon in the planning area, causing social and political conflicts. The high-density population of the Bay Area increases the likelihood of such conflicts, despite the existence of the Bay Area Water Supply and Conservation Agency Water Conservation Implementation Plan. The longer drought conditions last in the planning area, the more impacted the local economy becomes; water-dependent industries especially will experience setbacks.

9.7 ISSUES
The planning team has identified the following drought-related issues:
• Identification of the availability and reliability of new water supplies • Monitoring of the implementation and benefits of the long-term reliable water supply strategy projects, Bay Area Water Supply and Conservation Agency Water Conservation Implementation Plan projects, and water system upgrades
• Application of alternative techniques (groundwater recharge, water recycle, local capture and reuse, desalination, and transfer) to stabilize and offset Sierra Nevada snowpack water supply shortfalls 211
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• Regular occurrence of drought or multiyear droughts that may limit the planning area’s ability to successfully recover from or prepare for more occurrences-particularly noteworthy due to longevity of the current ongoing drought.
• The probability of increased drought frequencies and durations due to climate change • The promotion of active water conservation even during non-drought periods. 212
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10. EARTHQUAKE

10.1 GENERAL BACKGROUND
An earthquake is the vibration of the earth’s surface following a release of energy in the earth’s crust. This energy can be generated by a sudden dislocation of the crust or by a volcanic eruption. Most destructive quakes are caused by dislocations of the crust. The crust may first bend and then, when the stress exceeds the strength of the rocks, break and snap to a new position. In the process of breaking, vibrations called “seismic waves” are generated. These waves travel outward from the source of the earthquake at varying speeds.

10.1.1 Earthquake Location
The location of an earthquake is commonly described by its focal depth and the geographic position of its epicenter. The focal depth of an earthquake is the depth from the Earth’s surface to the region where an earthquake’s energy originates (the focus or hypocenter). The epicenter of an earthquake is the point on the Earth’s surface directly above the hypocenter.

10.1.2 Earthquake Geology
Tectonic Plates
The Earth’s crust, which is the rigid outermost shell of the planet, is broken into seven or eight major tectonic plates (depending on how they are defined) and many minor plates. Where the plates meet, they move in one of three ways along their mutual boundary: convergent (two plates moving together), divergent (two plates moving apart), or transform (two plates moving parallel to one another). Earthquakes, volcanic activity, mountainbuilding, and oceanic trench formation occur along these plate boundaries. Subduction is a geological process that takes place at convergent boundaries of tectonic plate, in which one plate moves under another. Regions where this process occurs are known as subduction zones, and they have the potential to generate highly damaging earthquakes.

California is seismically active because of movement of the North American Plate, east of the San Andreas Fault, and the Pacific Plate to the west, which includes the state’s coastal communities. The transform (parallel) movement of these tectonic plates against one another creates stresses that build as the rocks are gradually deformed. The rock deformation, or strain, is stored in the rocks as elastic strain energy. When the strength of the rock is exceeded, rupture occurs along a fault. The rocks on opposite sides of the fault slide past each other as they spring back into a relaxed position. The strain energy is released partly as heat and partly as elastic waves called seismic waves. The passage of these seismic waves produces the ground shaking in earthquakes. 213
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The sliding movement of earth on either side of a fault is called fault rupture. Fault rupture begins below the ground surface at the earthquake hypocenter, typically between 3 and 10 miles below the ground surface in California. If an earthquake is large enough, the fault rupture will travel to the ground surface, potentially destroying structures built across its path.

Faults
Geologists have found that earthquakes reoccur along faults, which are zones of weakness in the earth’s crust.

When a fault experiences an earthquake, there is no guarantee that all the stress has been relieved. Another earthquake can still occur. In fact, relieving stress along one part of a fault may increase it in another part.

Faults are more likely to have future earthquakes on them if they have more rapid rates of movement, have had recent earthquakes along them, experience greater total displacements, and are aligned so that movement can relieve the accumulating tectonic stresses. Geologists classify faults by their relative hazards. “Active” faults, which represent the highest hazard, are those that have ruptured to the ground surface during the Holocene period (about the last 11,000 years). “Potentially active” faults are those that displaced layers of rock from the Quaternary period (the last 1,800,000 years).

Determining if a fault is “active” or “potentially active” depends on geologic evidence, which may not be available for every fault. The majority of the seismic hazards are on well-known active faults. However, inactive faults, where no displacements have been recorded, also have the potential to reactivate or experience displacement along a branch sometime in the future. An example of a fault zone that has been reactivated is the Foothills Fault Zone. The zone was considered inactive until evidence of an earthquake (approximately 1.6 million years ago) was found near Spenceville, California. Then, in 1975, an earthquake occurred on another branch of the zone near Oroville, California (now known as the Cleveland Hills Fault). The State Division of Mines and Geology indicates that increased earthquake activity throughout California may cause tectonic movement along currently inactive fault systems.

10.1.3 Earthquake-Related Hazards
According to the U.S. Geological Survey (USGS) Earthquake Hazards Program, an earthquake hazard is anything associated with an earthquake that may affect people’s normal activities. This includes the following:
• Surface Faulting—Displacement that reaches the earth’s surface during slip along a fault. Commonly occurs with shallow earthquakes, those with an epicenter less than 20 kilometers. • Ground Motion (shaking)—The movement of the earth’s surface from earthquakes or explosions.

Ground motion or shaking is produced by waves that are generated by sudden slip on a fault or sudden pressure at the explosive source and travel through the earth and along its surface. • Landslide—A movement of surface material down a slope. • Liquefaction—A process by which water‐saturated sediment temporarily loses strength and acts as a fluid. Earthquake shaking can cause this effect.
• Tectonic Deformation—A change in the original shape of a material due to stress and strain. • Tsunami—A sea wave of local or distant origin that results from large‐scale seafloor displacements associated with large earthquakes, major submarine slides, or violent underwater volcanic eruptions. 214

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10.1.4 Earthquake Classifications
Earthquakes are typically classified in one of two ways: By the amount of energy released, measured as magnitude; or by the impact on people and structures, measured as intensity.

Magnitude
An earthquake’s magnitude is a measure of the energy released at the source of the earthquake. Magnitude is commonly expressed by ratings on the moment magnitude scale (Mw), the most common scale used today (Michigan Tech 2023). This scale is based on the total moment release of the earthquake (the product of the distance a fault moved and the force required to move it). The scale is as follows:
• Great—Mw > 8
• Major—Mw = 7.0 – 7.9
• Strong—Mw = 6.0 – 6.9
• Moderate—Mw = 5.0 – 5.9
• Light—Mw = 4.0 – 4.9
• Minor—Mw = 3.0 – 3.9
• Micro—Mw < 3
Intensity
The most commonly used intensity scale is the modified Mercalli intensity scale. Ratings of the scale as well as the perceived shaking and damage potential for structures are shown in Table 10-1. The modified Mercalli intensity scale is generally represented visually using shake maps, which show the expected ground shaking at any given location produced by an earthquake with a specified magnitude and epicenter. An earthquake has only one magnitude and one epicenter, but it produces a range of ground shaking throughout the region, depending on the distance from the earthquake, rock and soil conditions, and variations in the propagation of seismic waves from the earthquake. A shake map shows the range of ground shaking immediately following an earthquake.

Table 10-1. Mercalli Scale and Peak Ground Acceleration Comparison Modified Potential Structure Damage Estimated PGAa
Mercalli Scale Perceived Shaking Resistant Buildings Vulnerable Buildings (%g) I Not Felt None None <0.17%
II-III Weak None None 0.17% - 1.4%
IV Light None None 1.4% - 3.9%
V Moderate Very Light Light 3.9% - 9.2%
VI Strong Light Moderate 9.2% - 18%
VII Very Strong Moderate Moderate/Heavy 18% - 34%
VIII Severe Moderate/Heavy Heavy 34% - 65%
IX Violent Heavy Very Heavy 65% - 124%
X – XII Extreme Very Heavy Very Heavy >124%
a. PGA = peak ground acceleration. Measured in percent of g, where g is the acceleration of gravity

10.1.5 Ground Motion
Earthquake hazard assessment is based on expected ground motion. During an earthquake when the ground is shaking, it also experiences acceleration. The peak acceleration is the largest increase in velocity recorded by a particular station during an earthquake. Estimates are developed of the annual probability that certain ground motion accelerations will be exceeded; the annual probabilities can then be summed over a time period of interest. 215
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The most commonly mapped ground motion parameters are horizontal and vertical peak ground accelerations (PGA) for a given soil type. PGA is a measure of how hard the earth shakes, or accelerates, in a given geographic area. Instruments called accelerographs record levels of ground motion due to earthquakes at stations throughout a region. PGA is measured in g (the acceleration due to gravity) or expressed as a percent acceleration force of gravity (%g). These readings are recorded by state and federal agencies that monitor and predict seismic activity.

Maps of PGA values form the basis of seismic zone maps that are included in building codes such as the International Building Code. Building codes that include seismic provisions specify the horizontal force due to lateral acceleration that a building should be able to withstand during an earthquake. PGA values are directly related to these lateral forces that could damage “short period structures” (e.g., single-family dwellings). Longer period response components determine the lateral forces that damage larger structures with longer natural periods (e.g., apartment buildings, factories, high-rises, bridges). Table 10-1 lists damage potential and perceived shaking by PGA factors, compared to the Mercalli scale.

10.1.6 USGS Earthquake Mapping Programs
ShakeMaps
The USGS Earthquake Hazards Program produces maps called ShakeMaps that map ground motion and shaking intensity following significant earthquakes. ShakeMaps focus on the ground shaking caused by the earthquake, rather than on characteristics of the earthquake source, such as magnitude and epicenter. An earthquake has only one magnitude and one epicenter, but it produces a range of ground shaking at sites throughout the region, depending on the distance from the earthquake, the rock and soil conditions at sites, and variations in the propagation of seismic waves from the earthquake due to complexities in the structure of the earth’s crust.

A ShakeMap shows the extent and variation of ground shaking immediately across the surrounding region following significant earthquakes. Such mapping is derived from peak ground motion amplitudes recorded on seismic sensors, with interpolation where data are lacking based on estimated amplitudes. Color-coded instrumental intensity maps are derived from empirical relations between peak ground motions and Modified Mercalli intensity. In addition to the maps of recorded events, the USGS creates the following:
• Scenario ShakeMaps of hypothetical earthquakes of an assumed magnitude on known faults • Probabilistic ShakeMaps, based on predicted shaking from all possible earthquakes over a 10,000-year period. In a probabilistic map, information from millions of scenario maps are combined to make a forecast for the future. The maps indicate the ground motion at any given point that has a given probability of being exceeded in a given timeframe, such as a 100-year (1-percent-annual chance) event.

National Seismic Hazard Map
National maps of earthquake shaking hazards provide information for creating and updating seismic design requirements for building codes, insurance rate structures, earthquake loss studies, retrofit priorities and land use planning. After thorough review of the studies, professional organizations of engineers update the seismic-risk maps and seismic design requirements contained in building codes (Brown, et al. 2001). The USGS updated the National Seismic Hazard Maps in 2018. New seismic, geologic, and geodetic information on earthquake rates and associated ground shaking were incorporated into these revised maps. The 2018 map, shown in Figure 10-1, represents the best available data as determined by the USGS. 216

10. Earthquake
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Source: (USGS 2021)
Figure 10-1. Peak Acceleration (%g) with 2% Probability of Exceedance in 50 Years

10.1.7 Liquefaction and Soil Types
Soil liquefaction occurs when water-saturated sands, silts or gravelly soils are shaken so violently that the individual grains lose contact with one another and float freely in the water, turning the ground into a puddinglike liquid. Building and road foundations lose load-bearing strength and may sink into what was previously solid ground. Unless properly secured, hazardous materials can be released, causing significant damage to the environment and people.

A program called the National Earthquake Hazard Reduction Program (NEHRP) creates maps based on soil characteristics to help identify locations subject to liquefaction. NEHRP soil types define the locations that will be significantly impacted by an earthquake. Table 10-2 summarizes NEHRP soil classifications. NEHRP Soils B and C typically can sustain ground shaking without much effect, dependent on the earthquake magnitude. The areas that are commonly most affected by ground shaking have NEHRP Soils D, E and F. In general, these areas are also most susceptible to liquefaction. The areas that are most commonly affected by ground shaking have NEHRP Soils D, E and F.

10.1.8 Secondary Hazards
Earthquakes can cause disastrous landslides, often as a result of loss of cohesion in clay-rich soils. Earthen dams and levees are highly susceptible to seismic events, with the potential to fail following earthquakes. Earthquakes can also trigger tsunamis. Fires can result from gas lines or power lines that are broken or downed during the earthquake. It may be difficult to control a fire, particularly if the water lines feeding fire hydrants are also broken. 217
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Table 10-2. NEHRP Soil Classification System
NEHRP Soil
Type Description
Mean Shear Velocity to 30
m (m/s)
A Hard Rock 1,500
B Firm to Hard Rock 760-1,500
C Dense Soil/Soft Rock 360-760
D Stiff Soil 180-360
E Soft Clays < 180
F Special Study Soils (liquefiable soils, sensitive clays, organic soils, soft clays >36 m thick)

10.2 HAZARD PROFILE

10.2.1 Past Events
The last significant (> 6.0 M) seismic event in the Tri-Valley vicinity was the 2014 Magnitude-6.0 earthquake that originated 6 miles southwest of Napa. The previous large event was the 1989 M-7.1 Loma Prieta Earthquake that originated 10 miles northeast of Santa Cruz. No significant seismic events in the planning area vicinity have been recorded since these two events. Other significant earthquakes in California include the 1906 earthquake in San Francisco, the 1971 San Fernando Earthquake, and the 1994 Northridge earthquake. Recent earthquakes of magnitude of 4.0 or greater near the planning area are listed in Table 10-3. Figure 10-2 shows the locations of those with a magnitude of 5.0 or greater.

Table 10-3. Recent Earthquakes Magnitude 4.0 or Larger Near Planning Area Date Magnitude Epicenter Location
10/25/2022 5.1 9.3 miles (15km) southeast of Alum Rock, California 9/14/2022 4.4 1.86 miles (3km) north of Santa Rosa, California 10/15/2019 4.5 0.62 miles (1km) southeast of Pleasant Hill, California 07/16/2019 4.3 7.47 miles (12km) southwest of Byron, California 01/04/2018 4.4 1.24 miles (2km) southeast of Berkely, California 8/24/2014, South Napa Earthquake 6.0 South Napa
10/31/2007, Alum Rock Earthquake 5.6 San Francisco Bay area, California 5/14/2002, Gilroy Earthquake 5 Northern California
9/3/2000, Yountville Earthquake 5 Northern California
8/12/1998, San Juan Bautista Earthquake 5.2 Central California 4/18/1990, Northern California 5.4 Near Aromas, Northern California 10/18/1989, Loma Prieta Earthquake 7.1 10 miles northeast of Santa Cruz 8/8/1989, Santa Cruz County Earthquake 5.2 Central California 6/27/1989 5.3 Northern California
6/13/1988 5.3 San Francisco Bay area, California
2/20/1988 5.1 Central California
3/31/1986 5.6 Northern California
1/26/1986 5.4 Central California
Source: (USGS 2023)
California has been included in 13 FEMA major disaster (DR) or emergency (EM) declarations for earthquake events; however, Alameda County was included in only one: DR-845 for the October 17, 1989 Loma Prieta Earthquake; this declaration applied to the Counties of Alameda, Contra Costa, Marin, Monterey, Sacramento, San Benito, San Francisco, San Joaquin, San Mateo, Santa Clara, Santa Cruz, and Solano (FEMA 2017). 218

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Source: (USGS 2023)
Figure 10-2. Recent Earthquakes Magnitude 5.0 or Larger Near Planning Area M 5.6—Northern California
3/31/1986
M 5.6 – San Francisco Bay Area
10/31/2007
M 5.0 – San Francisco Bay Area
6/13/1988
M 7.2 – Northern California
10/18/1989, 8:15 p.m.

M 5.0—Northern California
6/27/1989, 4:25 p.m.

M 5.0—Northern California
5/14/2002
M 5.4—Northern California
4/18/1990
M 5.4—Central
California
1/26/1986
M 5.0—Central California
1/14/1986
M 5.0—Northern California
9/3/2000
M 6.0 – South Napa Earthquake
8/24/2014
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10.2.2 Location
Fault Locations
The planning area is located in a seismically active region, with exposure to major regional faults: Calaveras, Greenville, Hayward, Mount Diablo, and San Andreas. The primary seismic hazard is potential ground shaking.

Figure 10-3 shows the location of these fault lines and the probability of a major earthquake on each.

Calaveras Fault
The Calaveras Fault is a major branch of the San Andreas Fault, located east of the Hayward Fault. It extends 76 miles from the San Andreas Fault near Hollister to Danville at its northern end. The Calaveras Fault is one of the most geologically active and complex faults in the San Francisco Bay Area (USGS 2017). The probability of a M6.7 or greater earthquake along the Calaveras Fault within the next 30 years is 26 percent.

Greenville
The Greenville Fault is in the eastern Bay Area in Contra Costa and Alameda Counties. This dextral strike-slip fault zone borders the eastern side of Livermore Valley and is considered to be part of the larger San Andreas fault system in the central Coast Ranges. The fault zone extends from northwest of Livermore Valley along the Marsh Creek and Clayton Faults toward Clayton Valley.

Hayward Fault
The Hayward Fault is a 45-mile-long, right lateral slip fault that runs parallel to the San Andreas Fault through densely populated areas on the East Bay. The Hayward Fault is increasingly becoming a hazard priority in the Bay Area because of its increased chance for activity and its proximity to critical infrastructure and multiple highly populated areas. The probability of a M-6.7 or greater earthquake along the Hayward Fault within the next 30 years is 33 percent (USGS 2016).

Mount Diablo
The Mount Diablo thrust fault is in the vicinity of Mount Diablo in Contra Costa County. The fault lies between the Calaveras Fault, the Greenville Fault, and the Concord Fault, all right-lateral strike slip faults, and appears to transfer movement from the Calaveras and Greenville Faults to the Concord Fault, while continuing to uplift Mount Diablo.

San Andreas Fault
The San Andreas Fault extends 810 miles from the East Pacific rise in the Gulf of California through the Mendocino fracture zone off the shore of northern California. The fault is estimated to be 28 million years old. It is an example of a transform boundary exposed on a continent. The fault forms the tectonic boundary between the Pacific Plate and the North American Plate, and its motion is right-lateral strike-slip. The San Andreas Fault is typically referenced in three segments. The southern segment extends from its origin at the East Pacific Rise to Parkfield, California, in Monterey County. The central segment extends from Parkfield to Hollister, California.

The northern segment extends northwest from Hollister, through the Bay Area, to its ultimate junction with the Mendocino fracture zone and the Cascadia subduction zone in the Pacific Ocean. The probability of a M-6.7 or greater earthquake along the San Andreas Fault within the next 30 years is 22 percent (USGS 2016). 220

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Source: USGS, 2016c
Figure 10-3. Significant Known Faults in the Bay Area
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NEHRP Soil Type and Liquefaction Mapping
Figure 10-4 shows NEHRP soil classifications in San Mateo County. Figure 10-5 shows areas that have moderate, high or very high susceptibility to liquefaction.

Alquist-Priolo Zone Maps
California’s Alquist-Priolo Zone Maps provide regulatory zones for potential surface fault rupture where fault lines intersect with future development and populated areas. The purpose of these maps is to assist in the geologic investigation before construction begins to ensure that the resulting structure will not be located on an active fault.

The Tri-Valley planning area is located in a designated Alquist-Priolo Zone (California DOC 2023).

Alquist-Priolo maps were referenced, but not specifically used, in the assessment of risk for this plan. This plan assumes that the studies conducted and information provided by the State of California are the best available data for surface rupture risk and could not be improved through a separate assessment for this plan. Alquist-Priolo maps are available to the public on the California Department of Conservation website.

10.2.3 Frequency
California experiences hundreds of earthquakes each year, most with minimal damage and magnitudes below 3.0 on the Richter Scale. Earthquakes that cause moderate damage to structures occur several times a year. According to the USGS, a strong earthquake measuring greater than 5.0 occurs every 2 to 3 years and major earthquakes of more than 7.0 occur once a decade.

Both the San Andreas and the Hayward Faults have the potential for major to great events. The USGS estimated in 2016 that there is a 72 percent probability of at least one 6.7 or greater magnitude earthquake before 2043 that could cause widespread damage in the San Francisco Bay area (USGS 2016). The 2013 State of California MultiHazard Mitigation Plan cites projections that there is more than a 99-percent probability of a Magnitude-6.7 earthquake in California in the next 30 years and a 94-percent probability of a Magnitude-7.0 earthquake in California in the next 30 years. Probabilities for earthquakes on major fault lines in the San Francisco Bay Area were estimated by the USGS in a 2016 report, as summarized in Table 10-4.

Table 10-4. Earthquake Probabilities for the San Francisco Bay Area, 2014-2043 Fault
Probability of One or More
≥6.7 Quake, 2014-2043 Fault
Probability of One or More
≥6.7 Quake, 2014-2043
Hunting Creek 16% Maacama 8%
Green Valley 16% Rodgers Creek Fault 33%
Concord 16% Hayward 33%
Greenville 16% San Andreas 22%
Berryessa 16% San Gregorio 6%
Calaveras 26%
Source: (USGS 2016)
222
Figure 10-4
223
Figure 10-5
224

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10-13

10.2.4 Severity
Earthquakes can last from a few seconds to over five minutes; they may also occur as a series of tremors over a period of several days. The actual movement of the ground in an earthquake is seldom the direct cause of injury or death. Casualties generally result from falling objects and debris, because the shocks shake, damage or demolish buildings and other structures. Disruption of communications, electrical power supplies and gas, sewer and water lines should be expected. Earthquakes may trigger fires, dam failures, landslides or releases of hazardous material, compounding their disastrous effects.

The USGS has created ground motion maps based on current information about several fault zones. These maps show the PGA that has a certain probability (2 percent or 10 percent) of being exceeded in a 50-year period. The PGA is measured in numbers of g’s (the acceleration associated with gravity). Figure 10-6 shows the PGAs with a 10 percent exceedance chance in 50 years in the planning area.

Figure 10-6. PGA (as %g) with 10-Percent Probability of Exceedance in 50 Years

10.2.5 Warning Time
There is no current reliable way to predict the day or month that an earthquake will occur at any given location.

Research is being done with warning systems that use the low energy waves that precede major earthquakes.

These potential warning systems would give approximately 40 seconds notice that a major earthquake is about to occur. The warning time is very short, but it could allow for someone to get under a desk, step away from a hazardous material, or shut down a computer system. For example, MyShake is a global smartphone seismic network for early warning that can keep users informed about earthquakes. It monitors for earthquakes using data from smartphone sensors.
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10.3 EXPOSURE

10.3.1 Population
The entire population of the planning area (236,690) is potentially exposed to direct damage from earthquakes or indirect impacts such as business interruption, road closures, and loss of function of utilities. Figure 10-7 shows the estimated population of each planning area city living on NEHRP D soils, which make buildings more susceptible to damage from earthquakes, compared to total population. There are estimated to be 159,481 people in the total planning area living in these higher-risk areas, about 67 percent of the total population. Population served by DSRSD cannot be mapped to determine its exposure to the earthquake hazard.

Figure 10-7. Population Living on NEHRP D Soils and Total City Population, by Jurisdiction

10.3.2 Property
Figure 10-8 summarizes the number and value of buildings on NEHRP D soils in the planning area. Figure 10-9 shows the exposed total value as a percentage of the total replacement value in each city and in the overall planning area. Figure 10-10 shows the distribution by occupancy class of buildings on NEHRP D soils.

10.3.3 Critical Facilities
Critical facilities constructed on NEHRP Type D soils are particularly at risk from seismic events. Figure 10-11 shows the number of critical facilities on these soils, by category and jurisdiction. The total count of critical facilities on NEHRP Type D soils (905) represents 78 percent of the planning area total of 1,161.

10.3.4 Environment
The entire planning area is exposed to the earthquake hazard, including all natural resources, habitat, and wildlife. 36,822
(50.5% of Total)
68,658
(79.7% of Total)
54,001
(69.6% of Total)
72,932
86,149
77,609
0 20,000
40,000
60,000
80,000
100,000
Dublin Livermore Pleasanton
Population
Exposed Population
Total City Population
226

10. Earthquake
10-15
Figure 10-8. Number and Exposed Value of Buildings on NEHRP D Soils Figure 10-9. Total Value on NEHRP D Soils as Percent of Total Replacement Value, by Jurisdiction $33,805,216
$8,067,858,162
$11,296,579,051
$13,268,070,127
0 $5,733,617,613
$8,177,990,651
$10,357,107,907
Total Exposed Value
$33,805,216
(16 Buildings)
Total Exposed Value
$13,801,475,775
(8,060 Buildings)
Total Exposed Value
$19,474,569,702
(24,264 Buildings)
(16,843 Buildings), Total
Exposed Value,
$23,625,178,034
$0
$5,000,000,000
$10,000,000,000
$15,000,000,000
$20,000,000,000
$25,000,000,000
DSRSD Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value
15%

67.5%

65.4%

80.5%

71.5%
0% 20% 40% 60% 80% 100%
DSRSD
Dublin
Livermore
Pleasanton
Planning Area Total
Exposed Value as % of Total City or Area Replacement Value 227
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Figure 10-10. Number of Structures on NEHRP D Soils, by Occupancy Class Residential, 7,346
Residential, 22,485
Residential, 15,154
Commercial, 427
Commercial, 1,034
Commercial, 1,316
Industrial, 40
Industrial, 197
Industrial, 138
Agriculture, 11
Agriculture, 1
Agriculture, 0
Religion, 12
Religion, 83
Religion, 28
Government, 101
Government, 85
Government, 19
Education, 123
Education, 379
Education, 188
Dublin
Livermore
Pleasanton
0 5,000 10,000 15,000 20,000 25,000
Number of Structures on NEHRP D Soils
CITIES
Residential, 44,985
Commercial, 2,777
Industrial, 375
Agriculture, 12
Religion, 123
Government, 205
Education, 690
0 10,000 20,000 30,000 40,000 50,000
Number of Structures on NEHRP D Soils

PLANNING AREA TOTAL
228

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10-17
Figure 10-11. Critical Facilities on NEHRP D Soils, by Category and Jurisdiction

10.4 VULNERABILITY
Earthquake vulnerability data for the risk assessment was generated using a Hazus Level 2 (user-defined) analysis for the events listed in Table 10-5. Results are summarized in the sections below.

Table 10-5. Earthquakes Modeled for Risk Assessment
Fault Scenario Magnitude Epicenter Depth Epicenter Location PGA Calaveras (North) 6.86 5.8 miles Central San Ramon Figure 10-12 Greenville 6.86 7.0 miles 5.4 miles northeast of Central Livermore Figure 10-13 HayWireda 7.05 5.0 miles 9 miles northwest of Dublin Figure 10-14 Las Positas 6.5 6.0 miles 2.5 miles southeast of Central Livermore Figure 10-15 Mount Diablo Thrust South 6.5 5.6 miles 10 miles northeast of Central San Ramon Figure 10-16 a. “HayWired” is the name used by the USGS for an earthquake scenario featuring an event on the Hayward fault with a magnitude of

7.0. (U.S. Geological Survey 2018)
Communications, 0
Communications, 6
Communications, 13
Communications, 0
Energy, 0
Energy, 4
Energy, 2
Energy, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 1
Food, Water, Shelter, 40
Food, Water, Shelter, 16
Hazardous Material, 5
Hazardous Material, 263
Hazardous Material, 253
Hazardous Material, 0
Health & Medical, 13
Health & Medical, 19
Health & Medical, 30
Health & Medical, 0
Safety & Security, 34
Safety & Security, 37
Safety & Security, 35
Safety & Security, 0
Transportation, 32
Transportation, 47
Transportation, 55
Transportation, 0
Dublin
Livermore
Pleasanton
DSRSD
0 100 200 300 400
Number of Critical Facilities in the Flood Zone

PLANNING PARTNERS
Communications, 19
Energy, 6
Food, Water, Shelter, 57
Hazardous Material, 521
Health & Medical, 62
Safety & Security, 106
Transportation, 134
0 100 200 300 400 500 600 700
Number of Critical Facilities in the Flood Zone

PLANNING AREA TOTAL
229
Figure 10-12
230
Figure 10-13
231
Figure 10-14
232
Figure 10-15
233
Figure 10-16
234

10. Earthquake
10-23

10.4.1 Population
Displacement and Shelter Requirements
Impacts on persons and households in the planning area were estimated in Hazus for the five earthquake scenarios. Estimates for each city and the total planning area are presented in Figure 10-17 and Figure 10-18.

DSRSD does not have responsibility for sheltering or evacuation for displaced people.

Vulnerable Populations
While all people located in the NEHRP Class D and E Soils areas are considered exposed and potentially vulnerable, socially vulnerable populations include the very young, the elderly, and those of lower economic status. These socially vulnerable populations are most susceptible based on many factors, including their physical and financial ability to react or respond during a hazard and the ability to be self-sustaining for prolonged periods of time after an incident because of limited ability to stockpile supplies. Socially vulnerable populations may live in structures that do not conform to seismic building codes; therefore, homes will sustain more damage during an event. Local senior and disabled populations within the cities of Dublin, Livermore, and Pleasanton and those served by DSRSD may be especially vulnerable to earthquake events due to mobility challenges or reliance on medical devices such as oxygen supply tanks. Those experiencing homelessness are also especially vulnerable due to their lack of stable shelter and depending on their location, may be threatened by bridge or other structural collapse. Those who are economically challenged and inhabit structures that are not building code compliant or marginally structurally sound might have economic challenges performing repairs following an earthquake.

Additionally, emergency and urgent care medical facilities in the planning area could be impacted by a substantial earthquake. These facilities include Kaiser Permanente, Stanford Health Care, Veterans Health Care Livermore Division, Stanford Childrens Health, Axis Community Health, and others.

10.4.2 Property
Loss Potential
Property losses were estimated through the Hazus analysis for the five scenario events. Figure 10-19 summarizes the results for the overall planning area for structural loss, representing damage to building structures, and nonstructural loss, representing the value of lost contents and inventory, relocation, income loss, rental loss, and wage loss. Figure 10-20 through Figure 10-22 show the results for each planning area city.

Debris Estimates
The Hazus analysis also estimated the amount of earthquake-caused debris in the planning area for the five scenario events, as summarized in Figure 10-23.
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Figure 10-17. Estimated Number of Displaced Households Due to Earthquake Figure 10-18. Estimated Number of Persons Requiring Short-Term Shelter Due to Earthquake 9 0
42 0
1 2
22 20
54 15
32 1
70 4
2 43
23 132
58 18
0 20 40 60 80 100 120 140
Calaveras
Greenville
Haywired
Las Positas
Mount Diablo
Number of Displaced Households
Earthquake Scenario
Total Planning Area
Pleasanton
Livermore
Dublin
5 0
22 0
1 1
13 12
31 9
17 0
37 2
1 23
13 71
33 11
0 10 20 30 40 50 60 70 80
Calaveras
Greenville
Haywired
Las Positas
Mount Diablo
Number of Persons Requiring Short-Term Shelter
Earthquake Scenario
Total Planning Area
Pleasanton
Livermore
Dublin
236

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10-25
Figure 10-19. Loss Estimates for Earthquake, Total Planning Area Figure 10-20. Loss Estimates for Earthquake, City of Dublin Figure 10-21. Loss Estimates for Earthquake, City of Livermore $3,946,115,966
$3,191,098,331
$5,630,767,433
$3,470,111,881
$3,556,972,025
$1,663,202,328
$1,408,624,665
$2,450,436,156
$1,497,657,464
$1,547,319,074
Total Loss: $5,609,318,293 (7.0% of Total Value)
Total Loss: 4,599,722,996 (5.8% of Total Value)
Total Loss: $8,081,203,588 (10.2% of Total Value)
Total Loss: $4,967,769,344 (6.2% of Total Value)
Total Loss: $5,104,291,100 (6.4% of Total Value)
$0 $2,000,000,000 $4,000,000,000 $6,000,000,000 $8,000,000,000 $10,000,000,000 Calaveras
Greenville
Haywired
Las Positas
Mount Diablo
Estimated Loss Value
Earthquake Scenario
Contents Loss
Building Loss
$1,218,125,780
$637,880,080
$1,643,539,917
$416,611,869
$1,024,137,472
$465,480,521
$241,312,446
$642,315,272
$161,063,989
$387,922,085
Total Loss: $1,683,606,301 (8.2% of Total Value)
Total Loss: $879,192,525 (4.3% of Total Value)
Total Loss: $2,285,855,190 (11.2% of Total Value)
Total Loss: $577,675,859 (2.8% of Total Value)
Total Loss: $1,412,059,558 (6.9% of Total Value)
$0 $2,000,000,000 $4,000,000,000
Calaveras
Greenville
Haywired
Las Positas
Mount Diablo
Estimated Loss Value
Earthquake Scenario
Contents Loss
Building Loss
$812,849,628
$1,687,076,628
$1,489,389,125
$1,905,654,554
$1,434,700,906
$367,609,852
$772,134,699
$661,907,828
$837,478,436
$652,696,145
Total Loss: $1,180,459,480 (4.0% of Total Value)
Total Loss: $2,459,211,327 (8.3% of Total Value)
Total Loss: $2,151,296,953 (7.2% of Total Value)
Total Loss: $2,743,132,990 (9.2% of Total Value)
Total Loss: $2,087,397,051 (7.0% of Total Value)
$0 $2,000,000,000 $4,000,000,000
Calaveras
Greenville
Haywired
Las Positas
Mount Diablo
Estimated Loss Value
Earthquake Scenario
Contents Loss
Building Loss
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Figure 10-22. Loss Estimates for Earthquake, City of Pleasanton Figure 10-23. Estimated Earthquake-Caused Debris
Building Age
Table 10-6 identifies significant milestones in building and seismic code requirements that directly affect the structural integrity of development. Using these time periods, the planning team used Hazus to identify the number of structures in the planning area by date of construction. The number of structures does not reflect the number of total housing units, as many multi-family units are reported as one structure. Approximately 36 percent of the planning area’s structures were constructed after the Building Code was amended in 1994 to include seismic safety provisions. Approximately 1 percent were built before 1933 when there were no building permits, inspections, or seismic standards.
$1,915,140,558
$866,141,623
$2,497,838,390
$1,147,845,457
$1,098,133,647
$830,111,954
$395,177,520
$1,146,213,056
$499,115,039
$506,700,844
Total Loss: $2,745,252,512 (8.2% of Total Value)
Total Loss: $1,261,319,143 (4.3% of Total Value)
Total Loss: $3,644,051,446 (12.4% of Total Value)
Total Loss: $1,646,960,496 (5.6% of Total Value)
Total Loss: $1,604,834,491 (5.5% of Total Value)
$0 $2,000,000,000 $4,000,000,000
Calaveras
Greenville
Haywired
Las Positas
Mount Diablo
Estimated Loss Value
Earthquake Scenario
Contents Loss
Building Loss
Total Planning Area: 298.27
Total Planning Area: 261.47
Total Planning Area: 644.22
Total Planning Area: 276.00
Total Planning Area: 220.97
162.64

41.63 323.26

70.17 54.47

58.71 195.53
159.18
190.01
117.84

76.92 24.31
161.78

15.82 48.66
0 100 200 300 400 500 600 700
Calaveras
Greenville
Haywired
Las Positas
Mount Diablo
Debris from Structures (1,000s of tons)
Earthquake Scenario
Dublin
Livermore
Pleasanton
238

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10-27
Table 10-6. Age of Structures in Planning Area
Time Period Number of Current
Structures Built in Period Significance of Time Frame
Pre-1933 971 Before 1933, there were no explicit earthquake requirements in building codes. State law did not require local governments to have building officials or issue building permits. 1933-1940 253 In 1940, the first strong motion recording was made. 1941-1960 4.047 In 1960, the Structural Engineers Association of California published guidelines on recommended earthquake provisions.
1961-1975 20.629 In 1975, significant improvements were made to lateral force requirements. 1976-1994 18,746 In 1994, the Uniform Building Code was amended to include provisions for seismic safety. 1994 – present 25,409 Seismic code is currently enforced.

Total 70,055

10.4.3 Critical Facilities
Level of Damage
Hazus classifies the vulnerability of critical facilities to earthquake damage in five categories: no damage, slight damage, moderate damage, extensive damage, or complete damage. The model was used to assign a vulnerability category to each critical facility in the planning area. Figure 10-24 through Figure 10-28 show the results for the evaluated events as the average estimated probability for all facilities in each category.

Time to Return to Functionality
Hazus estimates the time to restore critical facilities to fully functional use. Results are presented as probability of being functional at specified time increments: 1, 3, 7, 14, 30 and 90 days after the event. For example, Hazus may estimate that a facility has 5 percent chance of being fully functional at Day 3, and a 95 percent chance of being fully functional at Day 90. Critical facilities were analyzed for the assessed earthquake scenarios. Figure 10-29 through Figure 10-33 show the results as the average estimated probability for all facilities in each category.

10.4.4 Environment
The environment vulnerable to earthquake hazard is the same as the environment exposed to the hazard.

Figure 10-24. Critical Facility Damage Potential, Calaveras Fault Scenario 51 53
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Energy
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Transportation
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Figure 10-25. Critical Facility Damage Potential, Greenville Fault Scenario Figure 10-26. Critical Facility Damage Potential, HayWired Fault Scenario Figure 10-27. Critical Facility Damage Potential, Las Positas Fault Scenario 79 27 0 0 0
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Figure 10-28. Critical Facility Damage Potential, Mt. Diablo Fault Scenario Figure 10-29. Critical Facility Functionality, Calaveras Fault Scenario Figure 10-30. Critical Facility Functionality, Greenville Fault Scenario 65 41
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Figure 10-31. Critical Facility Functionality, HayWired Fault Scenario Figure 10-32. Critical Facility Functionality, Las Positas Fault Scenario Figure 10-33. Critical Facility Functionality, Mt. Diablo Fault Scenario 0 10
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at Day 1 at Day 3 at Day 7 at Day 14 at Day 30 at Day 90 Probability of Being Fully functional
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10.5 FUTURE TRENDS IN DEVELOPMENT
Land use in the planning area will be directed by general plans adopted under California’s General Planning Law.

The safety elements of the general plans establish standards and plans for the protection of the cities from hazards.

The information in this plan provides a tool to ensure that there is no increase in exposure in areas of high seismic risk. Development in the planning area will be regulated through building standards and performance measures so that the degree of risk will be reduced. The geologic hazard portions of the planning area are heavily regulated under California’s General Planning Law. The International Building Code establishes provisions to address seismic risk.

10.6 SCENARIO
With the abundance of fault exposure in the Bay Area, the potential scenarios for earthquake activity are many.

An earthquake does not have to occur within the planning area to have a significant impact on the people, property and economy of the planning area.

Any seismic activity of 6.0 or greater on faults within the planning area would have significant impacts throughout the planning area. Potential warning systems could give approximately 40 seconds notice that a major earthquake is about to occur. This would not provide adequate time for preparation. Earthquakes of this magnitude or higher would lead to massive structural failure of property on NEHRP C, D, E, and F soils. Dams and revetments built on these poor soils would likely fail, representing a loss of critical infrastructure. These events could cause secondary hazards, including landslides and mudslides that would further damage structures.

Soil liquefaction would occur in water-saturated sands, silts or gravelly soils.

10.7 ISSUES
Important issues associated with an earthquake include the following:
• More information is needed on the exposure and performance of soft-story construction within the planning area.
• Based on the modeling of critical facility performance performed for this plan, a high number of facilities in the planning area are expected to have complete or extensive damage from scenario events. These facilities are prime targets for structural retrofits.
• Critical facility owner should be encouraged to create or enhance continuity of operations plans using the information on risk and vulnerability contained in this plan. • Geotechnical standards should be established that take into account the probable impacts from earthquakes in the design and construction of new or enhanced facilities. • There are a few dams that could affect a portion of the planning area. Dam failure warning and evacuation plans and procedures should be reviewed and updated to reflect the dams’ risk potential associated with earthquake activity in the region.
• Earthquakes could trigger other natural hazard events such as dam failures and landslides, which could severely impact the planning area.
• A worst-case scenario would be the occurrence of a large seismic event during a flood or high-water event. Dam failures would happen at multiple locations, increasing the impacts of the individual events. 243
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• Citizens are expected to be self-sufficient for up to three days after a major earthquake without government response agencies, utilities, private-sector services, and infrastructure components. Education programs are currently in place to facilitate development of individual, family, neighborhood, and business earthquake preparedness. Government alone can never make this region fully prepared. It takes individuals, families, and communities working in concert with one another to be fully prepared for disaster.
• After a major seismic event, the Tri-Valley planning area is likely to experience disruptions in the flow of goods and services resulting from the destruction of major transportation infrastructure across the broader region.
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11-1

11. FLOOD

11.1 GENERAL BACKGROUND

11.1.1 Types of Flooding Affecting the Planning Area
Flooding in the planning area typically occurs during the rainy season, between November and April. Three types of flooding primarily affect the planning area: stormwater flooding, riverine flooding and flash floods.

Stormwater Runoff Flooding
Urban drainage systems are designed to remove surface water from developed areas as quickly as possible to prevent flooding on streets and in other urban areas. These closed conveyance systems channel water away from an urban area to surrounding streams, bypassing natural processes of water filtration through the ground, containment, and evaporation of excess water. Urban drainage systems can play a role in flooding in two ways:
• Because drainage systems reduce the amount of time surface water takes to reach surrounding streams, flooding in those streams can occur more quickly and reach greater depths than prior to development in the area.
• If stormwater runoff exceeds the capacity of the drainage system, then stormwater runoff flooding can result throughout the system’s service area.

Stormwater runoff flooding can occur in areas other than delineated floodplains or along recognizable channels. It generally occurs in flat areas, and generally increases with urbanization, which speeds accumulation of floodwaters because of impervious areas. Shallow street flooding can occur unless channels have been improved to account for increased flows.

Riverine Flooding
Riverine flooding is overbank flooding of rivers and streams. Natural processes of riverine flooding add sediment and nutrients to fertile floodplain areas. Flooding in large river systems typically results from large-scale weather systems that generate prolonged rainfall over a wide geographic area, causing flooding in hundreds of smaller streams, which then drain into the major rivers. Two types of flood hazards are generally associated with riverine flooding:
• Inundation—Inundation occurs when floodwater is present and debris flows through an area not normally covered by water. These events cause minor to severe damage, depending on velocity and depth of flows, duration of the flood event, quantity of logs and other debris carried by the flows, and amount and type of development and personal property along the floodwater’s path. 245
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• Channel Migration—Erosion of banks and soils worn away by flowing water, combined with sediment deposition, causes migration or lateral movement of a river channel across a floodplain. A channel can also abruptly change location (termed “avulsion”); a shift in channel location over a large distance can occur within as short a time as one flood event.

The frequency and severity of flooding for river systems are based on discharge probability. The discharge probability is the probability that a certain river discharge (flow) level will be equaled or exceeded in a given year.

Flood studies use historical records to determine the probability of occurrence for different discharge levels and storm surge levels. These measurements reflect statistical averages only; it is possible for multiple floods with a low probability of occurrence (such as a 1-percent-annual-chance flood) to occur in a short time period. For riverine flooding, the same flood event can have flows at different points on a river that correspond to different probabilities of occurrence.

Shallow area flooding is a special type of riverine flooding. FEMA defines shallow flood hazards as areas inundated by the 1-percent-annual-chance flood with flood depths of only 1 to 3 feet. These areas are generally flooded by low-velocity sheet flows of water.

Flash Flooding
The National Weather Service defines flash flooding as flooding that begins within 6 hours of the heavy rainfall or other cause (NOAA 2022). Flash floods can tear out trees, undermine buildings and bridges, and scour new channels. In urban areas, flash flooding results from the removal of vegetation and replacement of ground cover with impermeable surfaces such as roads and parking lots. The greatest risk from flash floods is that they occur with little to no warning. The major factors in predicting potential damage are the intensity and duration of rainfall and watershed and stream steepness.

11.1.2 FEMA Regulatory Flood Zones
The extent of flooding associated with a 1 percent annual probability of occurrence (also called the base flood) is used as the regulatory boundary by many agencies. Also referred to as the special flood hazard area (SFHA), this boundary is a convenient tool for assessing vulnerability and risk in flood-prone communities. Many communities have maps that show the extent and likely depth of flooding for the base flood. Corresponding water-surface elevations for a given discharge level are among the most important factors used in estimating flood damage.

Mapped Flood Zones
FEMA defines flood hazard areas as areas expected to be inundated by a flood of a given magnitude. These areas are determined via statistical analyses of records of river flow, storm tides, and rainfall; information obtained through consultation with the community; floodplain topographic surveys; and hydrologic and hydraulic analyses.

Flood hazard areas are delineated on DFIRMs, which provide the following information:
• Locations of specific properties in relation to SFHAs • Base flood elevations (1-percent annual chance) at specific sites • Magnitudes of flood in specific areas
• Undeveloped coastal barriers where flood insurance is not available • Regulatory floodways and floodplain (1 percent and 0.2 percent annual chance) boundaries 246

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Land covered by floodwaters of the base flood is the special flood hazard area on a DFIRM—an area where NFIP floodplain management regulations must be enforced, and where mandatory purchase of flood insurance applies.

This regulatory boundary is a convenient tool for assessing vulnerability and risk in flood-prone communities, because many communities have maps showing the extent of the base flood and likely depths that will occur.

The base flood elevation (the water elevation of a flood that has a 1-percent chance of occurring in any given year) is one of the most important factors in estimating potential damage from flooding. A structure within a 1-percent-annual-chance floodplain has a 26-percent chance of undergoing flood damage during the term of a 30-year mortgage. The 1-percent-annual-chance flood is used by the NFIP as the basis for insurance requirements nationwide. DFIRMs also depict 0.2-percent-annual-chance flood designations.

DFIRMs and other flood hazard information can be used to identify the expected spatial extent of flooding from a 1-percent and 0.2-percent annual chance event. They depict the following SFHAs and other areas:
• Zone A (Also known as Unnumbered A-zones)—SFHAs where no base flood elevations or depths are shown because detailed hydraulic analyses have not been performed. • Zones A1-30 and AE—SFHAs that are subject to inundation by the base flood, determined using detailed hydraulic analysis. Base flood elevations are shown within these zones. • Zone AH—SFHAs that are subject to shallow flooding, usually in the form of a pond, with an average depth ranging from 1 to 3 feet. Base flood elevations derived from detailed analyses are shown at selected intervals within these zones.
• Zone AO—SFHAs subject to inundation by types of shallow flooding where average depths are between 1 and 3 feet. These are normally areas prone to shallow sheet flow flooding on sloping terrain. • Zone AR—Areas with a temporarily increased flood risk due to the building or restoration of flood control system (such as a levee or a dam). Mandatory flood insurance purchase requirements apply, but rates do not exceed the rates for unnumbered A zones if the structure is built or restored in compliance with Zone AR floodplain management regulations.
• Zone A99—Areas with a 1 percent annual chance of flooding that will be protected by a federal flood control system where construction has reached specified legal requirements. No depths or base flood elevations are shown within these zones.
• Zone B and X (shaded)—Zones where the land elevation as been determined to be above the base flood elevation, but below the 500-year flood elevation. These zones are not SFHAs. • Zones C and X (unshaded)—Zones where the land elevation has been determined to be above both the base flood elevation and the 500-year flood elevation. These zones are not SFHAs.

Floodways
The FEMA designated floodway is the channel of a water course and portion of the adjacent floodplain that is needed to convey the base flood without increasing flood levels by more than a specified amount (typically, 1 foot). A floodway may be designated within the SFHA where the deepest, highest velocity flow is expected and any infrastructure will be at risk. Floodways should be kept free of obstructions and development to allow floodwaters to move downstream unobstructed. Any development in a floodway is subject to severe damage and high risks for occupants and emergency responders.
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Unmapped Flood Areas
Flood damage may occur outside of SFHAs. FEMA typically does not designate SFHAs for areas subject to flooding from local drainage problems, particularly in urban areas; drainage basins of less than 1 square mile in area; or hillside areas subject to runoff, erosion, and mudflow. FEMA does not map flooding along the length of all streams or in areas that are undeveloped.

11.1.3 Floodplains
A floodplain is the area adjacent to a river, creek, lake or the ocean that becomes inundated during a flood.

Riverine floodplains may be broad, as when a river crosses an extensive flat landscape, or narrow, as when a river is confined in a canyon.

When floodwaters recede after a flood event, they leave behind layers of rock and mud. These gradually build up to create a new floor of the floodplain. Floodplains generally contain unconsolidated sediments (accumulations of sand, gravel, loam, silt, and/or clay), often extending below the bed of the stream. These sediments provide a natural filtering system, with water percolating back into the ground and replenishing groundwater. These are often important aquifers, the water drawn from them being filtered compared to the water in the stream. Fertile, flat reclaimed floodplain lands are commonly used for agriculture, commerce and residential development.

Connections between a river and its floodplain are most apparent during and after major flood events. These areas form a complex physical and biological system that not only supports a variety of natural resources but also provides natural flood and erosion control. When a river is separated from its floodplain with levees and other flood control facilities, natural, built-in benefits can be lost, altered, or significantly reduced.

Floodplain Ecosystems and Beneficial Functions
Floodplains can support ecosystems that are rich in plant and animal species. A floodplain can contain 100 or even 1,000 times as many species as a river. Wetting of the floodplain soil releases an immediate surge of nutrients: those left over from the last flood, and those that result from the rapid decomposition of organic matter that has accumulated since then. Microscopic organisms thrive, and larger species enter a rapid breeding cycle.

Opportunistic feeders (particularly birds) move in to take advantage. The production of nutrients peaks and falls away quickly, but the surge of new growth endures for some time. This makes floodplains valuable for agriculture. Species growing in floodplains are markedly different from those that grow outside floodplains. For instance, riparian trees (trees that grow in floodplains) tend to be very tolerant of root disturbance and very quickgrowing compared to non-riparian trees.

Floodplains have many natural beneficial functions, and disruption of them can have long-term consequences for entire regions. Some well-known, water-related functions of floodplains (noted by FEMA) include:
• Natural flood and erosion control
• Provide flood storage and conveyance
• Reduce flood velocities
• Reduce flood peaks
• Reduce sedimentation
• Surface water quality maintenance
• Filter nutrients and impurities from runoff
• Process organic wastes
• Moderate temperatures of water
• Provide groundwater recharge
• Promote infiltration and aquifer recharge
• Reduce frequency and duration of low surface flows
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Areas in the floodplain that typically provide these natural functions are wetlands, riparian areas, sensitive areas, and habitats for rare and endangered species.

Effects of Human Activities
Because they border water bodies, floodplains have historically been popular sites to establish settlements.

Human activities tend to concentrate in floodplains for a number of reasons: water is readily available; riverine floodplain land is fertile and suitable for farming; transportation by water is easily accessible; land is flatter and easier to develop; and there is value placed in ocean views. But human activity in floodplains frequently interferes with the natural function of floodplains. It can affect the distribution and timing of drainage, thereby increasing flood problems. Human development can create local flooding problems by altering or confining drainage channels or causing erosion of natural flood protection systems such as dunes. Flood potential can be increased in several ways: reducing a stream’s capacity to contain flows; increasing flow rates or velocities downstream; and allowing waves to extend further inland. Human activities can interface effectively with a floodplain as long as steps are taken to mitigate the activities’ adverse impacts on floodplain functions.

11.1.4 Secondary Hazards
The most problematic secondary hazard for flooding is bank erosion, which in some cases can be more harmful than actual flooding. This is especially true in the upper courses of rivers with steep gradients, where floodwaters may pass quickly and without much damage, but scour the banks, edging properties closer to the floodplain or causing them to fall in. Flooding is also responsible for hazards such as landslides when high flows over-saturate soils on steep slopes, causing them to fail. Hazardous materials spills are also a secondary hazard of flooding if storage tanks rupture and spill into streams, rivers or storm sewers.

11.2 HAZARD PROFILE

11.2.1 Federal Flood Program Participation
National Flood Insurance Program
The Cities of Dublin, Livermore and Pleasanton are all in good standing with the NFIP. Table 11-1 lists each municipal jurisdiction’s date of entrance into the NFIP and the effective date of its current FIRM. The first FIRMs in the planning area were available in 1977 to 1983. The date of the current effective FIRM for all three cities in the planning area is December 21, 2018. DSRSD, as a service provider and special district, does not participate in the NFIP.

Table 11-1. Jurisdictions and Date Joined NFIP
Jurisdiction NFIP Community # NFIP Entry Date Current Effective FIRM Dublin* 060705 August 18, 1983 December 21, 2018
Livermore 060008 July 5, 1977 December 21, 2018
Pleasanton 060012 December 16, 1980 December 21, 2018
San Ramon* 069710 September 27, 1985 June 16, 2009
Source: (FEMA 2022)
*Cities encompassing DSRSD Service Area
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Table 11-2 lists flood insurance statistics that help identify vulnerability within the planning area. The 361 policies in force provide more than $99.6 million in insurance. According to FEMA statistics, 23 flood insurance claims were paid between January 1, 1978, and April 30, 2022.

Table 11-2. Flood Insurance Statistics
Date of Entry Initial # of Flood Insurance Insurance Total Annual Claims Closed 11/1978 to
4/30/2022
FIRM Effective Date Policies as of 4/30/2022 In Force Premium Number Value Dublin 08/18/1983 91 $31,013,800 $150,817 3 N/A
Livermore 07/05/1977 177 $32,401,800 $105,042 1 N/A
Pleasanton 12/16/1980 93 $36,213,000 $78,978 19 $56,774 Total 361 $99,628,600 $334,837 23 $56,774
The Community Rating System
The Cities of Livermore and Pleasanton currently participate in the CRS program. Their CRS status is summarized in Table 11-3. Many of the mitigation actions identified in Volume 2 of this plan are creditable activities under the CRS program. Therefore, successful implementation of this plan offers the potential for these communities to enhance their CRS classifications and for currently non-participating communities to join the program.

Table 11-3. CRS Community Status in the Planning Area
Community
NFIP
Community # CRS Entry Date
Current CRS
Classification
% Premium Discount,
SFHA/non-SFHA
Livermore 060008 05/01/2015 6 20/10
Pleasanton 060012 10/1/1992 7 15/5
Total
Source: (FEMA 2022)

11.2.2 Primary Flood Sources
The factors that induce flooding in Alameda County are winter storms with heavy rainfall, steep topography, and constricted floodways. Storms of wide-area distribution originate over the Pacific Ocean in winter and develop with the frontal lifting of air masses along the hills of the coastal range.

City of Dublin
According to the effective 2018 FEMA Flood Insurance Study for Alameda County, the City of Dublin has flood problems similar to those of Alameda County, with heavy winter rainfall, a steep topography, and constricted floodways.

City of Livermore
According to the effective 2018 FEMA Flood Insurance Study for Alameda County, the principal flooding problems in the City occur during winter. Storm runoff is concentrated rapidly by the network of tributaries that discharge through the hills into the major streams. The tributaries have carved well-defined courses through the hills, but upon reaching the flat Livermore Valley, the channels become shallow and inadequate for lower returnfrequency flows. Constriction of Arroyo Seco flows at the Western Pacific and Southern Pacific Railroad crossing 250

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of the creek forces lower-frequency flood flows to spread out from these points. Another constricting hydraulic factor is a length of channel along Arroyo Las Positas upstream from Airway Boulevard. Rapid runoff rates, inadequate channels, and constricting structures combined with the development of some floodplain areas, make Livermore susceptible to damage when large rainstorms occur.

City of Pleasanton
According to the effective 2018 FEMA Flood Insurance Study for Alameda County, the main flooding problem is caused by the low capacity of the lower reaches of Arroyo De La Laguna, which causes backwater flooding in its tributary channels.

11.2.3 Past Events
Sources that provide historical information regarding previous occurrences and losses associated with flooding events in Alameda County and the planning area include FEMA, NWS, and NOAA’s National Centers for Environmental Information (NCEI). Between May 1953 and November 2022, FEMA issued disaster (DR) declarations for the State of California for 37 flood-related events, classified as one or a combination of the following: winter storms, debris and mud flows, severe winter storms, severe storms, mudslides, landslides, heavy rains, and high tides (FEMA 2022). Alameda County was included in 14 declarations, as listed in Table 11-4.

Little recorded information is available regarding previous flooding occurrences in the Cities of Dublin, Livermore and Pleasanton. Table 11-5 describes known flood events that impacted the planning area between 1970 and April 2023. Known flooding prior to that period of record in the Alameda Creek watershed includes the following (FEMA 2018):
• Several less-damaging floods from 1863 to 1888
• Five major floods and five less-damaging floods from 1889 to 1910 • Two major floods and 16 less-damaging floods between 1912 and 1945 • Flooding in 1950 with damage estimated at $1,100,000
• Flooding in 1952 with damage estimated at $1,500,0900 • Flooding in 1955 with damage estimated at $3,700,000
• Flooding in 1958 with damage estimated at $1,850,000
The flooding that occurred on December 23, 1955, the largest recorded, was mainly produced by overflow from Alameda Creek. The estimated peak discharge of 21,000 cfs on Alameda Creek near Niles exceeded the previous maximum of 18,500 cfs, recorded in January 1952. Residential damage was the greatest in the community of Niles east of the Union City corporate limits (FEMA 2018).

11.2.4 Location
Mapped Flood Zones
Flooding in the planning area has been documented by gage records, high water marks, damage surveys, and personal accounts. This documentation was the basis for the FEMA’s Alameda County FIRM. The FIRM’s mapped 1-percent annual chance floodplain is shown on Figure 11-1. Figure 11-2 summarizes the land area shown on the FIRM for each municipal planning partner in the 1- and 0.2-percent annual chance floodplains. 251
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Table 11-4. FEMA Disaster Declarations for Flood Events in Alameda County FEMA
Declaration
Number
Event Date Event Type Location
DR-4683 December 27, 2022 – January 31,
2023
Severe Winter Storms, Flooding, Landslides,
and Mudslides
44 counties including Alameda County
DR-4308 February 1 – February 23, 2017 Severe Winter Storms, Flooding, Mudslides 43 counties including Alameda County DR-4305 January 18 – January 23, 2017 Severe Winter Storms, Flooding, Mudslides 23 counties including Alameda County DR-4301 January 3 – January 12, 2017 Severe Winter Storms, Flooding, Mudslides 34 counties including Alameda County DR-1646 March 29 – April 16, 2006 Severe Storms, Flooding, Landslides, and Mudslides
17 counties including Alameda County
DR-1628 December 17 – January 3, 2006 Severe Storms, Flooding, Mudslides, and Landslides
31 counties including Alameda County
DR-1155 December 28, 1996 – April 1,
1997
Severe Storms, Flooding, Mud and Landslides 48 counties including Alameda County DR-1046 February 13 – April 19, 1995 Severe Winter Storms, Flooding, Landslides, Mud Flows
57 counties including Alameda County
DR-1044 January 3 – February 10, 1995 Severe Winter Storms, Flooding, Landslides, Mud Flows
42 counties including Alameda County
DR-758 February 12-March 10, 1986 Severe Storms & Flooding 39 counties including Alameda County DR-677 January 21 – March 30, 1983 Coastal Storms, Floods, Slides & Tornadoes 40 counties including Alameda County DR-1203 February 2 – April 30, 1998 Severe Winter Storms and Flooding 41 counties including Alameda County DR-651 December 19, 1981 – January 8,
1983
Severe Storms, Flood, Mudslides & High Tide 10 counties including Alameda County DR-283 February 16, 1970 Severe Storms & Flooding 17 counties including Alameda County Source: (FEMA 2023)
Table 11-5. Flood Events in the Tri-Valley Planning Area Event Date Event Type
FEMA
Declaration
Number
Location Description
December 27,
2022 – January
31, 2023
Severe Winter
Storms,
Flooding,
Landslides, and
Mudslides
DR-4683 44 counties
including
Alameda County
A series of nine atmospheric river events brought heavy rain, snow, substantial flooding, landslides, and mudslides to much of the state of California. The San Francisco Bay area experienced its wettest three-week period in 161 years.

December 13,
2021
Flooding,
Heavy Rain
N/A Bay Area
including
Alameda County
A low-pressure system descended from the Gulf of Alaska southward along the entire Pacific Coast and tapped into sub-tropical moisture originating from the Central Pacific to drop heavy rain throughout the state. A flash flood watch was issued for the Santa Lucia Mountains and Dolan Burn Scar area, where up to 12 inches of rain fell.

November 9,
2021
Atmospheric
River
N/A Bay Area
including
Alameda County
A weak to moderate atmospheric river event impacted the Bay Area November 8 and 9, bringing moderate to locally heavy rain and gusty winds. Several reports of roadway flooding were received, along with some downed powerlines and trees.
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Event Date Event Type
FEMA
Declaration
Number
Location Description
October 24,
2021
Atmospheric
River
N/A Bay Area
including
Alameda County
An early season atmospheric river brought heavy rain, urban and small stream flooding, strong winds, and high surf to the region.

Several downed trees were reported, along with wind gusts of 40 to 50 mph at lower elevations with 60 to 80 mph winds in the hills. One station in Alameda County reported a wind gust of 92 mph.

March 10, 2021 Flooding,
Heavy Rain,
Heavy Wind,
Hail
N/A Bay Area
including
Alameda County
A cold upper low moved through the region in early March bringing widespread showers and isolated thunderstorms to the Greater Bay Area. This system caused roadway flooding, debris flows, lightning, and small hail. Snow was also reported on some of the area’s peaks throughout the region as snow levels dropped down to 2,000 feet. A mudslide occurred along the River Fire burn scar in Monterey County sending mud and debris into nearby homes.

January 28,
2021
Atmospheric
River
N/A Countywide An atmospheric river caused flooding and debris flows over area burn scars as well as 15 to 20 inches of rain in the Santa Lucia Mountains. Mudflows near the River Fire burn scar in Monterey County caused damage to homes, covered roadways, and trapped animals at local ranches. Debris flows near the Dolan Fire burn scar caused an entire section of Highway 1 near Rat Creek to collapse into the Pacific Ocean.

April 5, 2020 Heavy Rain,
Flooding, Hail
N/A Bay Area
including
Alameda County
(Castro Valley)
A low-pressure system off the coast of northern California brought a cold front through the Bay Area. This system produced heavy rainfall, creating minor roadway flooding as well as gusty winds and scattered thunderstorms with small hail. Wind gusts across the higher elevations were observed between 35 and 65 mph. Breezy surface winds also downed several trees across the area.

January 16,
2020
Heavy Rain,
Flooding,
Heavy Wind
N/A Bay Area
including
Alameda County
A potent cold front swept through the region, bringing widespread rain, gusty winds, low elevation snow, and thunderstorms. This system brought widespread roadway flooding, downed trees, small hail, and snow as low as 2,400 feet in elevation.

December 7,
2019
Heavy Rain,
Heavy Wind,
Flooding
N/A Bay Area
including
Alameda County
A cold front swept through the region bringing gusty southerly winds, heavy rain, and flooding. Winds brought down trees and power lines across the greater Bay Area, resulting in injuries to two people in San Francisco. Downed power lines also left over 1,000 people without power in the Santa Cruz Mountains as well as causing several additional power outages across San Francisco.

November 30,
2019
Heavy Rain,
Flooding
N/A Bay Area
including
Alameda County
A low-pressure system moving in from the Gulf of Alaska and drawing in moisture from the tropics combined to bring the first atmospheric river event of the winter season to the Greater Bay Area. This system brought widespread heavy rainfall, roadway flooding, and strong winds to the region. These winds caused downed trees and power outages across the area.

February 13,
2019
Atmospheric
River, Flooding,
Debris Flow,
Heavy Wind
N/A Tri-Valley Area
(Livermore)
An atmospheric river with an associated cold front moved through the region bringing widespread flooding and debris flows. Multiple mainstem rivers flooded prompting evacuations from local officials. A tree fell on a car causing one fatality and one serious injury on Highway 17 while another downed tree caused a serious multi-car traffic accident that resulted in another fatality and multiple injuries. 253
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Event Date Event Type
FEMA
Declaration
Number
Location Description
February 21,
2017
Atmospheric
River
DR-4308 Countywide Widespread rain caused flooding, debris flow, accidents, and overtopping of reservoir spillways. In Livermore and Pleasanton, there were multiple road closures including westbound 580, westbound Stanley Blvd, Happy Valley Road. Ten people were stranded by flash flood in Livermore along Collier Canyon Road.

February 9,
2017
Atmospheric
River
DR-4308 Countywide Strong wind and heavy rain produced road flooding and debris flows.

November
30,2014
Rain and wind N/A Tri-Valley area Rain and wind brought a few downed trees and minor urban flooding. Heavy rain produced flooding on Interstate 580 onramp in Dublin and two westbound lanes were flooded in Livermore.

October 13,
2009
Heavy Rain
and wind
N/A Northern and
Central CA
Heavy rain and wind downed numerous trees and power lines.

Heavy rain caused major flooding on Bernal Avenue at Valley Avenue
March 29 –
April 16, 2006
Severe Storms,
Flooding,
Landslides, and
Mudslides
DR-1646 Countywide Strong storms brought heavy rain to most of Alameda County causing landslides, eroding hillsides and cracked pavement.

Oversaturated earth also caused landslide and/or erosion problems to private properties, which spilled over onto public rights-of-way.

December 17,
2005 –
January 12,
2006
Winter Storms
(Severe
Storms, Flood,
Mudslides,
Landslides)
DR-1628 Bay Area
including
Alameda County
Storms were blamed for two deaths from falling trees, around 50 businesses were declared damaged, and three homes were nearly wiped out by mudslides. The event included severe storms, flooding, mudslides, and landslides. Estimated damage was over $100 million.

February 3,
1998
Flash Flood N/A Tri-Valley area A levee breach along Arroyo Mocha damage roads and property in Dublin and Livermore. Estimated damage was $100,000.

December 28,
1996 – April 1,
1997
Severe Storms,
Flooding, Mud
and Landslides
DR-1155 48 counties
including
Alameda County
300 square miles in northern California were flooded and over 12,000 people were evacuated. Levee breaks were reported across the Sacramento and San Joaquin Valleys. Over 23,000 homes, business, agricultural lands, bridges, and roads were damaged.

Eight deaths resulted from this event. Overall, the state had $1.8 billion in damage.

January 3 –
February 10,
1995; and
February 13 –
April 19, 1995
Severe Winter
Storms,
Flooding,
Landslides,
Mud Flows
DR-1044
and DR1046
42 counties
including
Alameda County
Winter storms, flooding and landslides impacted a large area of the state. Storms in the Sacramento River Basin resulted in small stream flooding due to drainage system failures. Over 100 stations recorded their greatest one-day rainfall in history. Overall, there were 38 deaths, damage to homes and over $1.7 billion in damage.

February 12 –
March 10, 1986
Severe Storms
& Flooding
DR-758 Bay Area
including
Alameda County
The event damaged over 12,000 homes, destroyed over 1,300 homes, and caused 13 deaths and 67 injuries in California. Damage totaled over $407.5 million.

January 21 –
March 30, 1983
Coastal
Storms, Floods,
Slides &
Tornadoes
DR-677 40 counties
including
Alameda County
The state had over $500 million in damage from this event due to heavy rains, high winds, flooding, and levee breaks.

February 10,
1970
Severe Storms
& Flooding
DR-283 Bay Area
including
Alameda County
Heavy winds, storms and flooding impacted the Bay Area, including Alameda County. Impacted areas had over $27 million in damage.

Sources: (NOAA NCEI 2022 , NOAA 2023); (Association of Bay Area Governments 2010); (California Governor's Office of Emergency Services 2018)
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Figure 11-1
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Figure 11-2. Area in the Flood Zone, by Jurisdiction and Flood Event All principal flooding sources are incorporated in the currently effective FIRMs. The FIRMs are the most detailed and consistent data source available for determining flood extent. The effective 2018 Flood Insurance Study was used in this risk assessment to map the extent and location of the flood hazard.

Repetitive Loss
A repetitive loss property is an NFIP-insured property that has experienced repeated flood damage. A repetitive loss area is the portion of a floodplain holding structures that FEMA has identified as repetitive loss properties.

Identifying repetitive loss areas helps to identify structures that are at risk but are not on FEMA’s list of repetitive loss structures. The CRS program requires participating communities to identify repetitive loss areas. Based on information provided by FEMA Region 9 as of 2022, there are no repetitive loss structures within the city limits of Dublin or Livermore, and only one, a residence, in Pleasanton. The Pleasanton residence was not a severe repetitive loss structure. There were no severe repetitive loss structures in the planning area.

11.2.5 Frequency
According to NOAA NCEI, Alameda County has experienced 129 flood and flash flood events since 1996.

Table 11-6 shows these statistics, as well as the annual average number of events and the percent chance of each flood hazard occurring in Alameda County in any given year.

Table 11-6. Probability of Future Occurrences of Flood Events Hazard Type
Number of Occurrences Between
1996 and November 2022*
Rate of
Occurrence
Recurrence Interval
(in years)
% Chance of Occurrence in
Any Given Year
Flash Flood 26 0.65 1.58 63.4%
Flood 103 2.56 0.40 251.2%
TOTAL 129 Over 100%
Source: (NOAA NCEI 2022 )
*This table also includes the atmospheric river flood event of December 2022 – January 2023. 1% Annual Chance Flood Zone, 313
1% Annual Chance Flood Zone, 868
1% Annual Chance Flood Zone, 691
1% Annual Chance Flood Zone, 1,871

0.2% Annual Chance Flood Zone, 863

0.2% Annual Chance Flood Zone, 2,054

0.2% Annual Chance Flood Zone, 3,104

0.2% Annual Chance Flood
Zone, 6,020
Dublin
Livermore
Pleasanton
Planning
Area
0 2,000 4,000 6,000 8,000
Area in the Flood Zone (acres)
256

11. Flood
11-13
Smaller floods may occur on a more frequent basis and be categorized under a different hazard event type, most typically severe weather or severe storms. It is estimated that the planning area will experience the direct and indirect impacts of flooding each year, including urban flooding and smaller floods in identified flood-prone areas. These events may induce secondary hazards such as erosion, infrastructure deterioration or failure, utility failures, power outages, water quality and supply concerns, and transportation delays, accidents and inconveniences.

11.2.6 Severity
The principal factors affecting flood damage are flood depth and velocity. The deeper and faster flood flows become, the more damage they can cause. Shallow flooding with high velocities can cause as much damage as deep flooding with slow velocity. This is especially true when a channel migrates over a broad floodplain, redirecting high velocity flows and transporting debris and sediment. Flood severity is often evaluated by examining peak flow; Table 11-7 lists peak flows used by FEMA to map the floodplains of the planning area.

Table 11-7. Summary of Peak Discharges within the Planning Area Peak Flow (cubic feet/second)
Source/Location
10-Percent Annual
Chance
2-Percent Annual
Chance
1-Percent Annual
Chance

0.2-Percent Annual
Chance

ARROYO DE LA LAGUNA
Downstream of Arroyo Del Valle 7,000 13,500 17,000 28,000 Downstream of Arroyo Mocho 6,000 12,000 15,000 25,000

ARROYO DEL VALLE
Upstream of Arroyo De La Laguna 1,860 4,150 7,000 9,080

ARROYO LAS POSITAS
Upstream of confluence with Arroyo Mocho’ 1,800 1,800 1,800 1,800 At Gage (USGS No. 11176145) 2,000 4,200 5,000 6,700

ARROYO MOCHO
Upstream of Arroyo De La Laguna 4,520 11,500 13,700 20,600 Upstream of Chabot Canal 4,450 11,450 13,600 20,300
Upstream of Tassajara Creek 5,300 10,300 12,400 16,700
Downstream of Arroyo Las Positas 5,200 10,200 12,300 16,500 At USGS Gage No. 11176000 2,100 3,800 4,500 5,900
Upstream of Arroyo 1,900 1,900 1,900 1,900
Las Positas Near Garden Circle 5,000 7,800 9,100a 11,900 Upstream of Tassajara Creek 5,100 7,900 9,200a 12,100

CHABOT CANAL
At confluence with Arroyo Mocho 730 1,260 1,560 2,430

COLLIER CANYON CREEK
Near North Canyon Parkway 470 990 1,200 1,600
Downstream of Tributary 470 990 1,200 1,600
Upstream of Tributary 390 810 980 1,300
COLLIER CANYON TRIBUTARY 180 410 500 680

HEWLETT CANAL
At confluence with Chabot Canal 186 331 400 614
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Peak Flow (cubic feet/second)
Source/Location
10-Percent Annual
Chance
2-Percent Annual
Chance
1-Percent Annual
Chance

0.2-Percent Annual
Chance
LINE B-2-1
At Interstate Highway 680 830 1,500 1,840 2,850
Upstream of Western Pacific RR 680 1,210 1,500 2,060
Upstream of confluence with Line B-2-3 230 420 520 800
LINE G-3
At confluence with Arroyo Mocho 540 970 1,190 1,800
LINE J (ZONE 6) (CANADA DEL ALISO)
At confluence with Line E (Zone 6)
(Laguna Creek)
160 380 550 1,000

PLEASANTON CANAL
At confluence with Arroyo Del La Laguna 280 480 580 850

TASSAJARA CREEK
At confluence with Arroyo Mocho 1,540 3,200 4,140 6,900 a. Base flood elevations in the improved reach of Arroyo Mocho between Santa Rita and El Charro Roads are based on peak flows of 12,400 cubic feet per second at Santa Rita Road and 12,300 cubic feet per second at Garden Circle. These flows do not reflect overbank losses. The design flow for this reach of Arroyo Mocho is 12,500 cubic feet per second.

Source: (FEMA 2018)

11.2.7 Warning Time
Potential warning time available to a community for response to a flooding threat depends on the time between the first measurable rainfall and the first occurrence of flooding. The time needed to recognize a flood threat reduces potential warning time for a community. Because of the sequential pattern of weather conditions needed to cause serious flooding, occurrence of a flood without warning is unusual. Warning times for floods can be between 24 and 48 hours. Flash flooding can be less predictable, but populations in potential hazard areas can be warned in advance of flash flooding danger.

The National Weather Service (NWS) issues watches and warnings when forecasts indicate rivers may approach bank-full levels. Flood extent or severity categories used by NWS include minor flooding, moderate flooding, and major flooding, based on property damage and public threat:
• Minor Flooding—Minimal or no property damage, but possibly some public threat or inconvenience. • Moderate Flooding—Some inundation of structures and roads near streams. Some necessary evacuations of people and/or transfer of property to higher elevations. • Major Flooding—Extensive inundation of structures and roads. Significant evacuations of people and/or transfer of property to higher elevations (National Weather Service 2009b).

When a watch is issued, the public should prepare for the possibility of a flood. When a warning is issued, the public is advised to stay tuned to a local radio station for further information and be prepared to take quick action if needed. A warning means a flood is imminent, generally within 12 hours, or is occurring. Local media broadcast NWS warnings.
258

11. Flood
11-15

11.3 EXPOSURE
A quantitative assessment of exposure to the flood hazard was conducted using the flood mapping shown in Figure 11-1 and the asset inventory developed for this plan. Results for the planning area are presented below.

11.3.1 Population
All populations living in mapped flood zones are exposed to the risk of flooding. Figure 11-3 shows the estimated population for each planning area city living in the 1-percent and 0.2-percent annual chance floodplains, compared to total city population. Figure 11-4 shows results for the entire planning area. Population served by DSRSD cannot be mapped to determine its exposure to the flood hazard.

Figure 11-3. Population Exposed to Flood and Total City Population, by Jurisdiction Figure 11-4. Total Planning Area Population Exposed to Flood 486
(0.7% of Total)
153
(0.2% of Total) 1,550
(2.0% of Total)
2,366
(3.2% of Total) 3,991
(4.6% of Total)
17,700
(22.8% of Total)
72,932
86,149
77,609
0 20,000
40,000
60,000
80,000
100,000
Dublin Livermore Pleasanton
Population
Exposed Population, 1% Annual Chance Flood
Exposed Population, 0.2% Annual Chance Flood
Total City Population
2,189
(0.9% of Total)
24,057
(10.2% of Total)
236,690
(100.0% of Total)
0 50,000
100,000
150,000
200,000
250,000
Exposed Population, 1% Annual Chance
Flood Zone
Exposed Population, 0.2% Annual Chance
Flood Zone
Total Planning Area Population
Population
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11.3.2 Property
The estimated value of planning area buildings within the 1- and 0.2-percent-annual-chance flood zones is shown in Figure 11-5 and Figure 11-6. Figure 11-7 shows the estimated exposed total value as a percentage of the total replacement value in each city and in the overall planning area. The numbers of structures in each flood zone, by occupancy class, are shown in Figure 11-8 and Figure 11-9.

Figure 11-5. Number and Exposed Value of Buildings in the 1% Annual Chance Flood Zone Figure 11-6. Number and Exposed Value of Buildings in the 0.2% Annual Chance Flood Zone $2,112,826 $303,050,715 $253,372,807
$532,117,413
0 $272,640,169 $225,654,467
$361,294,202
Total Exposed Value
$2,112,826
(1 Buildings)
Total Exposed Value
$575,690,883
(157 Buildings)
Total Exposed Value
$479,027,274
(132 Buildings)
(492 Buildings), Total
Exposed Value,
$893,411,615
$0
$2,000,000,000
$4,000,000,000
$6,000,000,000
$8,000,000,000
$10,000,000,000
DSRSD Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value
$8,451,304
$1,716,779,951
$1,147,204,599
$4,507,938,483
0 $1,352,616,869
$1,058,870,067
$3,596,111,231
Total Exposed Value
$8,451,304
(4 Buildings)
Total Exposed Value
$3,069,396,820
(2,366 Buildings)
Total Exposed Value
$2,206,074,665
(3,991 Buildings)
(17,700 Buildings), Total
Exposed Value,
$8,104,049,714
$0
$2,000,000,000
$4,000,000,000
$6,000,000,000
$8,000,000,000
$10,000,000,000
DSRSD Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value
260

11. Flood
11-17
Figure 11-7. Total Value in Flood Areas as Percent of Total Replacement Value, by Jurisdiction Figure 11-8. Structures in the 1% Annual Chance Flood Zone, by Jurisdiction and Occupancy Class

2.8%

15.0%

1.6%

7.4%

3.0%

27.6%

2.4%

16.8%
0% 20% 40% 60% 80% 100%
10% Annual-Chance
Flood
1% Annual-Chance
Flood

0.2% AnnualChance Flood
Exposed Value as % of Total City or Area Replacement Value Dublin
Livermore
Pleasanton
Planning Area Total
Residential, 97
Residential, 50
Residential, 435
Commercial, 55
Commercial, 53
Commercial, 56
Industrial, 0
Industrial, 0
Industrial, 0
Agriculture, 1
Agriculture, 0
Agriculture, 0
Religion, 2
Religion, 27
Religion, 0
Government, 2
Government, 2
Government, 1
Education, 0
Education, 0
Education, 0
Dublin
Livermore
Pleasanton
0 100 200 300 400 500
Number of Structures in the Flood Zone
CITIES
Residential, 582
Commercial, 164
Industrial, 0
Agriculture, 1
Religion, 29
Government, 5
Education, 0
0 100 200 300 400 500 600 700
Number of Structures in the Flood Zone

PLANNING AREA TOTAL
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Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements 11-18
Figure 11-9. Structures in the 0.2% Annual Chance Flood Zone, by Jurisdiction and Occupancy Class

11.3.3 Critical Facilities
Estimates of critical facilities in the 1- and 0.2-percent annual chance flood hazard areas are summarized in Figure 11-10 and Figure 11-11. Critical facilities exposed to the flood hazard represent the following percentages of all critical facilities in the planning area:
• 7 percent (77 facilities) of all critical facilities are in the 1 percent-annual-chance flood hazard area. • 23 percent (265 facilities) of all critical facilities are in the 0.2 percent-annual-chance flood hazard area.

11.3.4 Environment
Because floodplain management measures place restrictions on development in areas affected by flooding, floodplains often have a higher portion of area that is undeveloped open space or natural area. These undeveloped areas represent environment exposed to the flood hazard.

Residential, 472
Residential, 1,307
Residential, 4,967
Commercial, 212
Commercial, 148
Commercial, 342
Industrial, 5
Industrial, 33
Industrial, 5
Agriculture, 1
Agriculture, 0
Agriculture, 0
Religion, 3
Religion, 28
Religion, 5
Government, 16
Government, 5
Government, 2
Education, 12
Education, 1
Education, 54
Dublin
Livermore
Pleasanton
0 1,000 2,000 3,000 4,000 5,000 6,000
Number of Structures in the Flood Zone
CITIES
Residential, 6,746
Commercial, 702
Industrial, 43
Agriculture, 1
Religion, 36
Government, 23
Education, 67
0 2,000 4,000 6,000 8,000
Number of Structures in the Flood Zone

PLANNING AREA TOTAL
262

11. Flood
11-19
Figure 11-10. Critical Facilities in the 1-Percent Annual Chance Flood Zone, by Category and Jurisdiction Communications, 0
Communications, 1
Communications, 0
Communications, 0
Energy, 0
Energy, 0
Energy, 0
Energy, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 3
Food, Water, Shelter, 1
Hazardous Material, 2
Hazardous Material, 4
Hazardous Material, 3
Hazardous Material, 0
Health & Medical, 2
Health & Medical, 0
Health & Medical, 1
Health & Medical, 0
Safety & Security, 3
Safety & Security, 0
Safety & Security, 0
Safety & Security, 0
Transportation, 20
Transportation, 17
Transportation, 20
Transportation, 0
Dublin
Livermore
Pleasanton
DSRSD
0 10 20 30 40 50
Number of Critical Facilities in the Flood Zone

PLANNING PARTNERS
Communications, 1
Energy, 0
Food, Water, Shelter, 4
Hazardous Material, 9
Health & Medical, 3
Safety & Security, 3
Transportation, 57
0 20 40 60 80 100
Number of Critical Facilities in the Flood Zone

PLANNING AREA TOTAL
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Figure 11-11. Critical Facilities in the 0.2-Percent Annual Chance Flood Zone, by Category and Jurisdiction

11.4 VULNERABILITY
Many of the areas exposed to flooding may not experience serious flooding or flood damage. This section describes vulnerabilities in terms of population, property, critical facilities, and the environment.

Communications, 0
Communications, 1
Communications, 5
Communications, 0
Energy, 0
Energy, 0
Energy, 0
Energy, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 12
Food, Water, Shelter, 4
Hazardous Material, 4
Hazardous Material, 45
Hazardous Material, 73
Hazardous Material, 0
Health & Medical, 6
Health & Medical, 3
Health & Medical, 10
Health & Medical, 0
Safety & Security, 9
Safety & Security, 1
Safety & Security, 7
Safety & Security, 0
Transportation, 25
Transportation, 29
Transportation, 31
Transportation, 0
Dublin
Livermore
Pleasanton
DSRSD
0 20 40 60 80 100
Number of Critical Facilities in the Flood Zone

PLANNING PARTNERS
Communications, 6
Energy, 0
Food, Water, Shelter, 16
Hazardous Material, 122
Health & Medical, 19
Safety & Security, 17
Transportation, 85
0 50 100 150
Number of Critical Facilities in the Flood Zone

PLANNING AREA TOTAL
264

11. Flood
11-21

11.4.1 Population
Impacts on population in the planning area were estimated for the 1- and 2-percent annual chance flood events.

Estimates for each city and the total planning area are presented in Figure 11-12 and Figure 11-13. DSRSD does not have any responsibility for sheltering or evacuation of displaced people.

Figure 11-12. Estimated Number of Displaced Persons Due to Flood Figure 11-13. Estimated Number of Persons Requiring Short-Term Shelter Due to Flood Vulnerable Populations
Socially vulnerable populations are susceptible to the flood hazard based on many factors, including their physical and financial ability to react or respond during a hazard event and the location and construction quality of their housing. Economically disadvantaged populations are likely to evaluate their risk and make decisions based on the major economic impact on their family and may not have funds to evacuate. 51 629
19 1,288
279
9,078
350
10,995
0 2,000 4,000 6,000 8,000 10,000 12,000
1% Annual Chance Flood

0.2% Annual Chance Flood
Number of Displaced Persons
Flood Event
Total Planning Area
Pleasanton
Livermore
Dublin
12 64
4 119
46 544
62 727
0 100 200 300 400 500 600 700 800
1% Annual
Chance Flood

0.2% Annual
Chance Flood
Number of Persons Requiring Short-Term Shelfter
Flood Event
Total Planning Area
Pleasanton
Livermore
Dublin
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The aftermath of flooding events presents numerous threats to public health and safety, including unsafe food, contaminated drinking and washing water and poor sanitation, mosquitoes and animals, mold and mildew, carbon monoxide poisoning, and mental stress and fatigue. These impacts pose a unique risk to the local at-risk senior and disabled populations in Dublin, Livermore, and Pleasanton and those served by DSRSD due to existing health conditions and the increased need for proper nutrition.

Since the homeless population is often transient, they may be at risk during a flood event resulting in their displacement. The ability to notify them in advance may be limited since they most likely do not have immediate access to technology, such as email, cell phone, notifications, and alerts. Their ability to relocate or access and shelter may also be limited due to lack of transportation.

11.4.2 Property
Impacted Buildings
Impacted structures are those with finished floor elevations below the flood event water surface elevation. These structures are the most likely to receive significant damage in a flood event. Figure 11-14 shows the estimated number of buildings in Dublin, Livermore, and Pleasanton impacted by the flood events evaluated for this risk assessment.

Figure 11-14. Estimated Number of Buildings Impacted by Flood Damage to Structures and Contents
Using historical flood insurance claim data, Hazus estimates the percentage of damage to structures and their contents by applying established damage functions to an inventory. For this analysis, local data on facilities was used instead of the default inventory data provided with Hazus. The analysis is summarized in Figure 11-15 through Figure 11-18 for the overall planning area and each planning area city. 1 4
77 241
71 376
274
2,607
422
3,224
0 500 1,000 1,500 2,000 2,500 3,000 3,500
1% Annual
Chance Flood

0.2% Annual
Chance Flood
Number of Displaced Persons
Number of Buildings Impacted by Flood
Total Planning Area
Pleasanton
Livermore
Dublin
DSRSD
266

11. Flood
11-23
Figure 11-15. Loss Estimates for Flood, Total Planning Area Figure 11-16. Loss Estimates for Flood, City of Dublin
Figure 11-17. Loss Estimates for Flood, City of Livermore $40,685,019
$581,494,199
$31,772,176
$989,076,266
Total Loss: $72,457,195
Total Loss: $1,570,570,465 (0.1% of Total Value)
$0 $2,000,000,000
1% Annual Chance
Flood

0.2% Annual Chance
Flood
Estimated Loss Value
Earthquake Scenario
Contents Loss
Building Loss
$5,689,950
$172,953,053
$6,612,196
$291,149,217
Total Loss: $12,302,145
Total Loss: $464,102,270 (0.1% of Total Value)
$0 $2,000,000,000
1% Annual Chance
Flood

0.2% Annual Chance
Flood
Estimated Loss Value
Earthquake Scenario
Contents Loss
Building Loss
$1,947,166
$126,594,107
$6,182,609
$371,963,836
Total Loss: $8,129,774 (0.02% of Total Value)
Total Loss: $498,557,943 (0.0% of Total Value)
$0 $2,000,000,000
1% Annual Chance
Flood

0.2% Annual Chance
Flood
Estimated Loss Value
Earthquake Scenario
Contents Loss
Building Loss
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Figure 11-18. Loss Estimates for Flood, City of Pleasanton Flood-Caused Debris
The Hazus analysis estimated the amount of flood-caused debris within the planning area generated by flooding, as summarized in Figure 11-19.

Figure 11-19. Estimated Flood-Caused Debris
$33,047,903
$281,947,038
$18,977,372
$325,963,213
Total Loss: $52,025,275
Total Loss: $607,910,252 (0.2% of Total Value)
$0 $2,000,000,000
1% Annual Chance
Flood

0.2% Annual Chance
Flood
Estimated Loss Value
Earthquake Scenario
Contents Loss
Building Loss
34 37,632
18 6,724
0 30,741
52 75,097
0 10,000 20,000 30,000 40,000 50,000 60,000 70,000 80,000 1% Annual Chance Flood

0.2% Annual Chance Flood
Debris from Structures (Tons)
Flood Event
Total Planning Area
Pleasanton
Livermore
Dublin
268

11. Flood
11-25

11.4.3 Critical Facilities
Hazus was used to estimate the number of critical facilities affected by flooding and the resulting percent of damage to the building and contents. The estimated number of affected critical facilities and damage as a percent of total value are shown in Figure 11-20 and Figure 11-21 for the evaluated flood events. For the 1 percentannual-chance-event, the average amount of damage to structures, measured as a percentage of total value, ranges from 0 to 9 percent of total value and average damage to contents ranges from 0 to 38 percent, depending on critical facility category.

Figure 11-20. Estimated Damage to Critical Facilities from 1% Annual Chance Flood Figure 11-21. Estimated Damage to Critical Facilities from 0.2% Annual Chance Flood 0.0 0.0 0.09.0 0.0 0.0 0.0 0.0 7.0 1.3 14.7 0.0 38.0

0.0 0 0 1
9 3 1
24 0
25 50
75 100
125
0 10
20 30
40 50
Communications Energy Food, Water,
Shelter
Hazardous
Materials
Health/Medical Safety/Security Transportation
Number of Facilities Affected
Average Damage as % of Total Value
% Damage to Structure % Damage to Contents Number of Facilities Affected

0.00.00.00.04.15.63.84.61.3 16.4

10.1 13.2

25.6 0.0
0 0
11 122
19 11
47 0
25 50
75 100
125
0 10
20 30
40 50
Communications Energy Food, Water,
Shelter
Hazardous
Materials
Health/Medical Safety/Security Transportation
Number of Facilities Affected
Average Damage as % of Total Value
% Damage to Structure % Damage to Contents Number of Facilities Affected 269
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Significant facilities predicted by Hazus to be affected by the 1 percent-annual-chance flood include the following:
• 1 primary education facilities
• 5 hazardous materials facilities
• 1 medical care facility
• 24 bridges

11.4.4 Environment
Flooding can impact the environment in negative ways. Migrating fish can wash into roads or over dikes into flooded fields, with no possibility of escape. Pollution from roads, such as oil, and hazardous materials can wash into rivers and streams. During floods, these can settle onto normally dry soils, polluting them for agricultural uses. Human development, such as bridge abutments, levees, or logjams from timber harvesting, can increase stream bank erosion, causing rivers and streams to migrate into non-natural courses.

Loss estimation platforms such as Hazus are not currently equipped to measure environmental impacts of flood hazards. The best gauge of vulnerability of the environment would be a review of damage from past flood events.

Loss data that segregates damage to the environment was not available at the time of this plan. Capturing this data from future events could be beneficial in measuring the vulnerability of the environment for future updates.

11.5 FUTURE TRENDS IN DEVELOPMENT
The planning partners are equipped to handle future growth within flood hazard areas. All three cities have general plans that address frequently flooded areas in their safety elements and have committed to linking their general plans to this hazard mitigation plan. This will create an opportunity for wise land use decisions as future growth impacts flood hazard areas. Additionally, the three cities participant in the NFIP and have adopted flood damage prevention ordinances in response to its requirements. They have committed to maintaining their good standing under the NFIP through actions identified in this plan.

11.6 SCENARIO
The primary water courses in the planning area have the potential to flood at irregular intervals, generally in response to a succession of intense winter rainstorms. Storm patterns of warm, moist air usually occur between early November and late March. A series of such weather events can cause severe flooding in the planning area.

The worst-case scenario is a series of storms that flood numerous drainage basins in a short time. This could overwhelm the response and floodplain management capability within the planning area. Major roads could be blocked, preventing critical access for many residents and critical functions. High in-channel flows could cause water courses to scour, possibly washing out roads and creating more isolation problems.

11.7 ISSUES
The planning team has identified the following flood-related issues relevant to the planning area:
• The accuracy of the existing flood hazard mapping produced by FEMA in reflecting the true flood risk within the planning area is questionable. This is most prevalent in areas protected by privately owned levees and levees not accredited by the FEMA mapping process. 270

11. Flood
11-27
• The extent of the flood-protection currently provided by flood control facilities (dams, dikes and levees) is not known due to the lack of an established national policy on flood protection standards. • Older levees are subject to failure or do not meet current building practices for flood protection. • The risk associated with the flood hazard overlaps the risk associated with other hazards such as earthquake, landslide and wildfire. This provides an opportunity to seek mitigation alternatives with multiple objectives that can reduce risk for multiple hazards. • More information is needed on flood risk to support the concept of risk-based analysis of capital projects. • There needs to be a sustained effort to gather historical damage data, such as high water marks on structures and damage reports, to measure the cost-effectiveness of future mitigation projects. • Ongoing flood hazard mitigation will require funding from multiple sources. • There needs to be a coordinated hazard mitigation effort between jurisdictions affected by flood hazards within and outside of the planning area.
• Floodplain residents need to continue to be educated about flood preparedness and the resources available during and after floods.
• The concept of residual risk should be considered in the design of future capital flood control projects and should be communicated with residents living in the floodplain. • The promotion of flood insurance as a means of protecting private property owners from the economic impacts of frequent flood events should continue.
• Existing floodplain-compatible uses such as agricultural and open space need to be maintained. There is constant pressure to convert these existing uses to more intense uses within the planning area during times of moderate to high growth.
271
272
12-1

12. LANDSLIDE

12.1 GENERAL BACKGROUND

12.1.1 Landslide Types
According to the USGS, the term landslide includes a wide range of ground movements. Landslides are commonly categorized by the type of initial ground failure, the material carried, or the nature of the movement.

They include the following:
• Block slides—Blocks of rock that slide along a slip plane as a unit down a slope. • Creep—A slow-moving landslide often only noticed through crooked trees and disturbed structures. • Debris avalanche—A debris flow that travels faster than about 10 miles per hour (mph). Speeds in excess of 20 mph are not uncommon, and speeds in excess of 100 mph, although rare, can occur. The slurry can travel miles from its source, growing as it descends, picking up trees, boulders, cars, and anything else in its path.
• Earth flows—Fine-grained sediments that flow downhill and typically form a fan structure. • Mudslides or Debris Flows—Rivers of rock, earth, organic matter and other soil materials saturated with water. They develop in the soil overlying bedrock on sloping surfaces when water rapidly accumulates in the ground, such as during heavy rainfall or rapid snowmelt. • Rock falls—Blocks of rock that fall away from a bedrock unit without a rotational component. • Rock topples—Blocks of rock that fall away from a bedrock unit with a rotational component. • Rotational slumps—Blocks of fine-grained sediment that rotate and move down slope. • Transitional slides—Sediments that move along a flat surface without a rotational component.

12.1.2 Landslide Risk Areas
Landslides are typically a function of soil type and steepness of slope. Soil type is a key indicator for landslide potential and is used by geologist and geotechnical engineers to determine soil stability for construction standards.

In general, landslide hazard areas are where the land has characteristics that contribute to the risk of the downhill movement of material, such as the following:
• A slope greater than 33 percent
• Post-wildfire areas
• A history of landslide activity or movement during the last 10,000 years 273
Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements 12-2
• Stream or wave activity, which has caused erosion, undercut a bank or cut into a bank to cause the surrounding land to be unstable
• The presence or potential for snow avalanches
• The presence of an alluvial fan, indicating vulnerability to the flow of debris or sediments • The presence of impermeable soils, such as silt or clay, mixed with granular soils, such as sand or gravel.

The best predictor of where slides might occur is the location of past movements. Past landslides can be recognized by their distinctive topographic shapes, which can remain in place for thousands of years. Most landslides recognizable in this fashion range from a few acres to several square miles. Most show no evidence of recent movement and are not currently active. A small proportion of them may become active in any given year, with movements concentrated within all or part of the landslide masses or around their edges. The recognition of ancient dormant landslide sites is important in the identification of areas susceptible to flows and slides because they can be reactivated by earthquakes or by exceptionally wet weather. Also, because they consist of broken materials and frequently involve disruption of groundwater flow, these dormant sites are vulnerable to construction-triggered sliding.

12.1.3 Landslide Causes
Landslides are caused by a combination of geological and climate conditions and the influence of urbanization.

They can be initiated by storms, earthquakes, fires, volcanic eruptions, or human modification of the land.

Vulnerable natural conditions are affected by human development and the infrastructure that supports it. In some cases, irrigation increases the landslide potential. The following factors can contribute to slide formation:
• Change in slope of the terrain
• Increased load on the land
• Shocks and vibrations
• Change in water content
• Groundwater movement
• Frost action
• Weathering of rocks
• Removing or changing the vegetation covering slopes.

While small landslides are frequently a result of human activity, the largest landslides are often naturally occurring phenomena with little or no human contribution.

12.1.4 Landslide Management
Landslides can create immediate, critical threats to public safety. They can move rapidly down slopes or through channels, and can strike with little or no warning. Effective landslide management should include the following elements:
• Continuing investigation to identify natural landslides, understand their mechanics, assess their risk to public health and welfare, and understand their role in ecological systems • Regulation of development in or near existing landslides or areas of natural instability through the cities’ codes and ordinances and Alameda County code.
• Preparation for emergency response to landslides to facilitate rapid, coordinated action among Alameda County, the planning area, and state and federal agencies, and to provide emergency assistance to affected or at-risk citizens
274

12. Landslide
12-3
• Evaluation of options including landslide stabilization or structure relocation where landslides are identified as a threat to critical public structures or infrastructure

12.1.5 Secondary Hazards
Mass movements are not generally known to result in secondary hazards. A landslide that blocks a river or stream does have the potential to cause flooding.

12.2 HAZARD PROFILE

12.2.1 Past Events
Landslides in the Bay Area typically occur either as a result of an earthquake or during heavy and sustained rainfall events. Urbanized areas, like the Cities of Dublin, Livermore and Pleasanton, and especially hilly areas of Alameda and Contra Costa County, have sustained damage from landslides caused by storms. Between January 1980 and May 2022, FEMA issued disaster (DR) declarations for the State of California for 11 landslide hazardrelated events that affected Alameda or Contra Costa County, classified as one or a combination of the following events: severe winter storms, flooding, debris flow, mud flows, landslides and mudslides, as listed in Table 12-1.

Table 12-1. FEMA Landslide Disaster Declarations in Alameda County FEMA Declaration Event Date Event Type Location
DR-4308 February 1 – February 23,
2017 Severe Winter Storms, Flooding, Mudslides 43 counties including Alameda and Contra Costa DR-4305 January 18 – January 23,
2017 Severe Winter Storms, Flooding, Mudslides 23 counties including Alameda and Contra Costa DR-4301 January 3 – January 12,
2017 Severe Winter Storms, Flooding, Mudslides 34 counties including Alameda and Contra Costa DR-1646 March 29 – April 16, 2006 Severe Storms, Flooding, Landslides, and Mudslides 17 counties including Alameda
DR-1628 December 17 – January 3,
2006
Severe Storms, Flooding, Mudslides, and
Landslides
31 counties including Alameda and
Contra Costa
DR-1155 December 28, 1996 – April
1, 1997
Severe Storms, Flooding, Mud and
Landslides
48 counties including Alameda and
Contra Costa
DR-1046 February 13 – April 19,
1995
Severe Winter Storms, Flooding, Landslides,
Mudslides
57 counties including Alameda and
Contra Costa
DR-1044 January 3 – February 10,
1995
Severe Winter Storms, Flooding, Landslides,
Mudslides
42 counties including Alameda and
Contra Costa
DR-979 January 5 – March 20,
1993
Severe Storms, Flooding, Mud and
Landslides
27 counties including Contra
Costa
DR-677 January 21 – March 30,
1983 Coastal Storms, Floods, Slides & Tornadoes 40 counties including Alameda and Contra Costa DR-651 December 19, 1981 –
January 8, 1983 Severe Storms, Flood, Mudslides & High Tide 10 counties including Alameda and Contra Costa Source: (FEMA 2022)
Little recorded information is available regarding previous landslide occurrences in the Cities of Dublin, Livermore, and Pleasanton. Table 12-2 lists known landslide events that have impacted the planning area between January 1980 and May 2022.
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Table 12-2. Landslide Events in the Tri-Valley Planning Area Event Date Event Type
FEMA
Declaration Location Description
February 13,
2019
Flooding and
Debris Flows
N/A Livermore Widespread flooding and debris flows prompted evacuations.

March 8, 2017 Landslide N/A Pleasanton The backyards of three homes along Foothill Road slid/eroded into Arroyo De La Laguna Creek in Pleasanton.

February 20,
2017
Slide DR-4308 Livermore Slide blocked at least one land east bound 84 just west of Vallecitos and Tesla Road closed from mudslide in Livermore.

January 19,
2017
Mudslides DR-4305 Tri-Valley area/
unincorporated
county
Mudslide debris covered Palomares Road, Tesla Road, Mines Road, and Old Altamont Pass Road.

November 2,
2015
Mudslide N/A Livermore/
unincorporated
county
Heavy rain caused mudslide on Patterson Pass Road, Tesla Road and Corral Hollow Road, east of Livermore
April 6-20,
2006
Heavy Rain
and Debris
Flows
DR-1646 Alameda
County
Heavy rains caused landslides, eroding hillsides and cracked pavement. Landslide or erosion problems on private properties spilled over onto county rights-of-way. Overall, the County had approximately $10 million in damage to county roadways.

December 17,
2005 –
January 12,
2006
Winter Storms DR-1628 Alameda
County
Severe storms brought flooding, mudslides, and landslides to most of Alameda County.

February 1995 Late Winter
Storms
(Severe Winter
Storms, Flood,
Landslide,
Mudflows)
DR-1046 Statewide All California counties except Del Norte were included in this declaration. In total, the state recorded 17 deaths; $190.6 million in public property damage, $122.4 million in individual damage, $46.9 million in business damage, $79 million in highway damage, and $651.6 million in agricultural damage; with 1,322 homes recording major damage, 267 listed as destroyed, and 2,299 recording minor damage.

Sources: (National Climatic Data Center 2022); (FEMA 2022); (Alameda County 2021)

12.2.2 Location
The California Geological Survey developed statewide mapping of landslide susceptibility classes based on regional rock strength and slope. The mapping assumed that landslide susceptibility is low on very low slopes in all rock materials and increases with slope and in weak rocks. The analysis factored in locations of past landslides. Figure 12-1 shows the planning area susceptibility classes—low, moderate, high, and very high/existing landslide. Most of the planning area has low susceptibility, though portions of all the cities’ boundaries have moderate to high susceptibility. Western Pleasanton has very high susceptibility.

12.2.3 Frequency
Landslides are often triggered by events such as earthquakes, heavy rain, floods, or wildfires, so landslide frequency is often related to the frequency of these other hazards. In the planning area, landslides typically occur during and after major storms, so the potential for landslides largely coincides with the potential for sequential severe storms that saturate steep, vulnerable soils. The probability of a landslide event occurring in the planning area in any given year is high. Table 12-1 lists 10 federal disaster declarations for landslides in Alameda County between 1981 and May 2022, an average of once every four years. Table 12-2 lists eight landslide events in the Tri-Valley planning area between 1995 and May 2022, which averages about one event every three or four years. 276
Figure 12-1
277
Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements 12-6

12.2.4 Severity
Landslides destroy property and infrastructure and can take human lives. Slope failures in the United States result in about 25 to 50 deaths per year and damage costing over $1 billion (U.S. Geological Survey n.d.). Landslides can pose a serious hazard to properties on or below hillsides. When landslides occur—in response to such changes as increased water content, earthquake shaking, addition of load, or removal of downslope support—they deform and tilt the ground surface. The result can be destruction of foundations, offset of roads, breaking of underground pipes, or overriding of downslope property and structures. In the planning area, landslides and mudslides have caused damage to homes, public facilities, roads, parks, and sewer lines in particular. Landslides can vary widely in extent, from a single rock tumbling down a hillside, to a major landslide or mudflow that covers several acres.

12.2.5 Warning Time
Mass movements can occur suddenly or slowly. The velocity of movement may range from a slow creep of inches per year to many feet per second, depending on slope angle, material and water content. Generally accepted warning signs for landslide activity include the following:
• Springs, seeps, or saturated ground in areas that have not typically been wet before • New cracks or unusual bulges in the ground, street pavements or sidewalks • Soil moving away from foundations
• Ancillary structures such as decks and patios tilting and/or moving relative to the main house • Tilting or cracking of concrete floors and foundations • Broken water lines and other underground utilities
• Leaning telephone poles, trees, retaining walls or fences • Offset fence lines
• Sunken or down-dropped roadbeds
• Rapid increase in creek water levels, possibly accompanied by increased turbidity (soil content) • Sudden decrease in creek water levels though rain is still falling or just recently stopped • Sticking doors and windows, and visible open spaces indicating frames out of plumb • A faint rumbling sound that increases in volume as the landslide nears • Unusual sounds, such as trees cracking or boulders knocking together.

Some methods used to monitor mass movements can provide an idea of the type of movement and the amount of time prior to failure. Assessing the geology, vegetation, and amount of predicted precipitation for an area can help in predictions of what areas are at risk during general time periods. Currently, there is no practical warning system for individual landslides.
278

12. Landslide
12-7

12.3 EXPOSURE

12.3.1 Population
Population exposure was estimated by calculating the number of buildings in each landslide susceptibility zone withing the planning area as a percent of total planning area buildings, and then applying this percentage to the estimated planning area population. Figure 12-2 shows the estimated population for each planning area city living in the moderate, high, and very high landslide susceptibility zones, compared to total city population. Figure 12-3 shows results for the entire planning area. Population served by DSRSD cannot be mapped to determine its exposure to the landslide hazard.

Figure 12-2. Population Exposed to Landslide Hazard and Total City Population, by Jurisdiction Figure 12-3. Total Planning Area Population Exposed to Landslide Hazard 15,113
(20.7% of Total)
2,486
(2.9% of Total)
5,181
(6.7% of Total)
19,834
(27.2% of Total)
2,568
(3.0% of Total)
9,447
(12.2% of Total)
195
(0.3% of Total) 0
(0.0% of Total) 1,204
(1.6% of Total)
72,932
86,149
77,609
0 20,000
40,000
60,000
80,000
100,000
Dublin Livermore Pleasanton
Population
Exposed Population, Moderate Landslide Susceptibility
Exposed Population, High Landslide Susceptibility
Exposed Population, Very High Landslide Susceptibility
Total City Population
22,780
(9.6% of Total)
31,849
(13.5% of Total)
1,400
(0.6% of Total)
236,690
0 50,000
100,000
150,000
200,000
250,000
Exposed Population, Moderate
Landslide Suscepitility
Exposed Population, High
Landslide Suscepitility
Exposed Population, Very High
Landslide Suscepitility
Total Planning Area Population
Population
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12.3.2 Property
The estimated value of planning area buildings within the moderate, high, and very high landslide susceptibility zones is shown in Figure 12-4 through Figure 12-6. Figure 12-7 shows the estimated exposed total value as a percentage of the total replacement value in each city and in the overall planning area. The numbers of structures in each susceptibility zone, by occupancy class, are shown in Figure 12-8 through Figure 12-10.

DSRSD does not have any exposure for this zone
Figure 12-4. Number and Exposed Value of Buildings in the Moderate Landslide Susceptibility Zone Figure 12-5. Number and Exposed Value of Buildings in the High Landslide Susceptibility Zone $1,571,676,713
$364,550,892
$651,480,256
$850,402,975
$212,773,376 $338,675,881
Total Exposed Value
$2,422,079,687
(3,085 Buildings)
Total Exposed Value
$577,324,268
(856 Buildings)
Total Exposed Value
$990,156,138
(1,466 Buildings)
$0
$500,000,000
$1,000,000,000
$1,500,000,000
$2,000,000,000
$2,500,000,000
Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value
$52,820,650
$2,489,713,410
$530,530,964
$1,631,778,279
0 $1,329,842,434
$378,884,651
Total Exposed Value $942,001,580
$52,820,650
(25 Buildings)
Total Exposed Value
$3,819,555,843
(4,040 Buildings)
Total Exposed Value
$909,415,615
(929 Buildings)
(2,776 Buildings), Total
Exposed Value,
$2,573,779,859
$0
$500,000,000
$1,000,000,000
$1,500,000,000
$2,000,000,000
$2,500,000,000
$3,000,000,000
$3,500,000,000
$4,000,000,000
$4,500,000,000
DSRSD Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value
280

12. Landslide
12-9
DSRSD does not have any exposure for this zone
Figure 12-6. Number and Exposed Value of Buildings in the Very High Landslide Susceptibility Zone Figure 12-7. Total Value in Landslide Susceptibility Zones as % of Total Replacement Value, by City $53,000,424 $0
$249,510,481 $31,751,112 $0 $130,888,166
Total Exposed Value
$84,751,536
(41 Buildings)
Total Exposed Value
$0
( Buildings)
Total Exposed Value
$380,398,647
(349 Buildings)
$0
$1,000,000,000
$2,000,000,000
$3,000,000,000
$4,000,000,000
Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value
0%

24.30%
0 11.8%

18.7%

0.4%

1.9%

3.1%

0.0%

3.4%

8.8%

1.3%

5.0%

9.2%

0.6%
0% 20% 40% 60% 80% 100%
Moderate Landslide
Susceptibility
High Landslide
Susceptibility
Very High Landslide
Susceptibility
Exposed Value as % of Total City or Area Replacement Value DSRSD
Dublin
Livermore
Pleasanton
Planning Area Total
281
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Figure 12-8. Structures in the Moderate Landslide Susceptibility Zone, by Jurisdiction and Occupancy Class Figure 12-9. Structures in the High Landslide Susceptibility Zone, by Jurisdiction and Occupancy Class Residential, 3,015
Residential, 814
Residential, 1,454
Commercial, 10
Commercial, 14
Commercial, 5
Industrial, 0
Industrial, 0
Industrial, 0
Agriculture, 0
Agriculture, 0
Agriculture, 0
Religion, 4
Religion, 1
Religion, 5
Government, 17
Government, 4
Government, 0
Education, 39
Education, 23
Education, 2
Dublin
Livermore
Pleasanton
0 1,000 2,000 3,000 4,000 5,000
Number of Structures in the Landslide Hazard Zone
CITIES
Residential, 5,283
Commercial, 29
Industrial, 0
Agriculture, 0
Religion, 10
Government, 21
Education, 64
0 2,000 4,000 6,000 8,000
Number of Structures in the Landslide Hazard Zone

PLANNING AREA TOTAL
Residential, 3,957
Residential, 841
Residential, 2,651
Commercial, 16
Commercial, 24
Commercial, 79
Industrial, 4
Industrial, 20
Industrial, 17
Agriculture, 5
Agriculture, 0
Agriculture, 0
Religion, 4
Religion, 0
Religion, 3
Government, 37
Government, 10
Government, 0
Education, 17
Education, 34
Education, 26
Dublin
Livermore
Pleasanton
0 1,000 2,000 3,000 4,000 5,000
Number of Structures in the Landslide Hazard Zone
CITIES
Residential, 7,449
Commercial, 119
Industrial, 41
Agriculture, 5
Religion, 7
Government, 47
Education, 77
0 2,000 4,000 6,000 8,000
Number of Structures in the Landslide Hazard Zone

PLANNING AREA TOTAL
282

12. Landslide
12-11
Figure 12-10. Structures in Very High Landslide Susceptibility Zone, by Jurisdiction and Occupancy Class

12.3.3 Critical Facilities
Estimates of critical facilities in the mapped landslide susceptibility zones are summarized in Figure 12-11. The total count of critical facilities in high or very high landslide susceptibility zones (98) represents 8 percent of the planning area total of 1,161.

12.3.4 Environment
All natural areas within the high susceptibility zones for landslide are considered to be exposed to the hazard.

Residential, 39
Residential, 0
Residential, 338
Commercial, 0
Commercial, 0
Commercial, 9
Industrial, 0
Industrial, 0
Industrial, 2
Agriculture, 2
Agriculture, 0
Agriculture, 0
Religion, 0
Religion, 0
Religion, 0
Government, 0
Government, 0
Government, 0
Education, 0
Education, 0
Education, 0
Dublin
Livermore
Pleasanton
0 100 200 300 400
Number of Structures in the Landslide Hazard Zone
CITIES
Residential, 377
Commercial, 9
Industrial, 2
Agriculture, 2
Religion, 0
Government, 0
Education, 0
0 100 200 300 400
Number of Structures in the Landslide Hazard Zone

PLANNING AREA TOTAL
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Tri-Valley Local Hazard Mitigation Plan; Volume 1—Planning-Area-Wide Elements 12-12
Figure 12-11. Critical Facilities in the High or Very High Landslide Susceptibility Zone

12.4 VULNERABILITY
Vulnerability estimates for the landslide hazard are described qualitatively. No loss estimation of these facilities was performed because damage functions have not been established for the landslide hazard.

12.4.1 Population
According to the CDC, health threats from landslides include the following (CDC 2018):
• Trauma caused by rapidly moving water and debris
• Broken electrical, water, gas and sewage lines that can lead to injury or illness • Disrupted roadways that can endanger motorists and disrupt transport and access to health care Communications, 0
Communications, 0
Communications, 1
Communications, 0
Energy, 0
Energy, 0
Energy, 1
Energy, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 26
Food, Water, Shelter, 25
Hazardous Material, 0
Hazardous Material, 1
Hazardous Material, 13
Hazardous Material, 0
Health & Medical, 0
Health & Medical, 0
Health & Medical, 3
Health & Medical, 0
Safety & Security, 2
Safety & Security, 1
Safety & Security, 2
Safety & Security, 0
Transportation, 11
Transportation, 4
Transportation, 8
Transportation, 0
Dublin
Livermore
Pleasanton
DSRSD
0 10 20 30 40
Number of Critical Facilities in the Flood Zone

PLANNING PARTNERS
Communications, 1
Energy, 1
Food, Water, Shelter, 51
Hazardous Material, 14
Health & Medical, 3
Safety & Security, 5
Transportation, 23
0 20 40 60 80
Number of Critical Facilities in the Flood Zone

PLANNING AREA TOTAL
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12-13
Landslide events can hinder evacuation routes, prevent the delivery of necessary goods to vulnerable populations in the Tri-Valley planning area, and delay emergency and medical responses to the area. Local vulnerable populations, such as the senior community, schools, individuals without vehicles, and individuals with disabilities within the cities of Dublin, Livermore, and Pleasanton and those served by DSRSD, may also have a difficult time evacuating the affected area in time due to their circumstances. A landslide might also impact access to senior centers, the veteran center in Livermore, schools, and disadvantaged community centers.

12.4.2 Property
Figure 12-12 shows estimates of potential loss representing 10 percent, 30 percent, and 50 percent of the assessed value of structures exposed to the landslide hazard (for the moderate, high, and very high susceptibility zones combined). These estimates allow emergency managers to assess a range of economic impacts based on an estimate of the percent of damage to the general building stock. Damage in excess of 50 percent is considered to be substantial by most building codes and typically requires total reconstruction of the structure.

Figure 12-12. Loss Estimates for Landslide

12.4.3 Critical Facilities
There are 98 critical facilities exposed to the high or very high landslide susceptibility zone. No loss estimates were developed as a result of the lack of established damage functions for the landslide hazard.

DSRSD, $5,282,065
DSRSD, $15,846,195
DSRSD, $26,410,325
DSRSD, $52,820,650
Dublin, $632,638,707
Dublin, $1,897,916,120
Dublin, $3,163,193,533
Dublin, $6,326,387,067
Livermore, $148,673,988
Livermore, $446,021,965
Livermore, $743,369,941
Livermore, $1,486,739,883
Pleasanton, $394,433,464
Pleasanton, $1,183,300,393
Pleasanton, $1,972,167,322
Pleasanton, $3,944,334,644
$0 $2,000,000,000 $4,000,000,000 $6,000,000,000 $8,000,000,000 $10,000,000,000 $12,000,000,000 Loss = 10% of
Exposed Value
Loss = 30% of
Exposed Value
Loss = 50% of
Exposed Value
Exposed Value
Loss Value
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12.4.4 Environment
Environmental problems as a result of landslides can be numerous. Vegetation and wildlife habitats may be damaged or destroyed. Soil and sediment runoff accumulate downslope, potentially blocking waterways and roadways and impairing the quality of streams and other water bodies. Landslides that fall into streams may significantly impact fish and wildlife habitat, as well as affecting water quality. Hillsides that provide wildlife habitat can be lost for prolonged periods of time due to landslides.

12.5 FUTURE TRENDS IN DEVELOPMENT
The planning partners are equipped to handle future growth within landslide hazard areas. Landslide risk areas are addressed in the safety elements of local general plans. All three cities have committed to linking their general plans to this hazard mitigation plan. This will create an opportunity for wise land use decisions as future growth impacts landslide hazard areas.

Additionally, the State of California has adopted the International Building Code by reference in its California Building Standards Code. The Code includes provisions for geotechnical analyses in steep slope areas that have soil types considered susceptible to landslide hazards. These provisions assure that new construction is built to standards that reduce the vulnerability to landslide risk.

12.6 SCENARIO
Major landslides in the planning area occur as a result of soil conditions that have been affected by severe storms, groundwater or human development. The worst-case scenario for landslide hazards in the planning area would generally correspond to a severe storm that had heavy rain and caused flooding. Landslides are most likely during late winter when the water table is high. After heavy rains from November to December, soils become saturated with water. As water seeps downward through upper soils that may consist of permeable sands and gravels and accumulates on impermeable silt, it will cause weakness and destabilization in the slope. A short intense storm could cause saturated soil to move, resulting in landslides. As rains continue, the groundwater table rises, adding to the weakening of the slope. Gravity, poor drainage, a rising groundwater table and poor soil exacerbate hazardous conditions.

Landslides are becoming more of a concern as development moves outside of city centers into less-developed areas. It is probable that private and public property, including infrastructure, will be affected. Mass movements could affect bridges that pass over landslide-prone ravines and knock out rail service through the planning area.

Road obstructions caused by mass movements would create isolation problems for residents and businesses in sparsely developed areas. Property owners exposed to steep slopes may suffer damage to property or structures.

Landslides carrying vegetation such as shrubs and trees may cause a break in utility lines, cutting off power and communication access to residents.

12.7 ISSUES
Important issues associated with landslides in the planning area include the following:
• There are existing homes in landslide risk areas throughout the planning area. The degree of vulnerability of these structures depends on the codes and standards the structures were constructed to. Information to this level of detail is not currently available.
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• Future development could lead to more homes in landslide risk areas. • Mapping and assessment of landslide hazards are constantly evolving. As new data and science become available, assessments of landslide risk should be reevaluated. • The impact of climate change on landslides is uncertain. If climate change impacts atmospheric conditions, then exposure to landslide risks is likely to increase. • The risk associated with the landslide hazard overlaps the risk associated with other hazards such as earthquake, flood and wildfire. This provides an opportunity to seek mitigation alternatives with multiple objectives that can reduce risk for multiple hazards.
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13. SEVERE WEATHER

13.1 GENERAL BACKGROUND
Severe weather refers to any dangerous meteorological phenomena with the potential to cause damage, serious social disruption, or loss of human life. Severe weather conditions with the greatest potential to impact the planning area are described in the following sections. Flooding and landslides associated with severe weather are discussed as separate hazards in Chapters 11 and 12. In this risk assessment, the “severe weather” hazard refers in aggregate to the various weather conditions profiled—severe storms, extreme heat, damaging winds and space weather. These conditions are treated as a single hazard for the following reasons:
• Each condition has impacted the planning area, with similar frequencies of occurrence, based on weather records.
• Each condition impacts the entire planning area, with no clearly mapped or defined extent. Without a mapped or defined extent, quantitative, geospatial analysis to assess exposure or vulnerability is not available.

Therefore, the risk assessment for severe weather is qualitative and is based on the aggregate exposure and vulnerability to all weather conditions.

13.1.1 Severe Storms
Severe storm conditions in the planning area include heavy rain (atmospheric rivers and thunderstorms), lightning and hail. Heavy rain refers to events where the amount of rain exceeds normal levels. The amount of precipitation needed to qualify as heavy rain varies with location and season. Heavy rain is distinct from climate change analyses on increasing precipitation. It does not mean that the total amount of precipitation at a location has increased, just that the rain is occurring in a more intense event. More frequent heavy rain events, however, can serve as indicators of changing precipitation levels. Heavy rain is most frequently measured by tracking the frequency of events, analyzing the mean return period, and measuring the amount of precipitation in a certain period (most typically inches of rain within a 24-hour period) (Environmental Protection Agency 2021).

Thunderstorms
NOAA classifies a thunderstorm as a storm with lightning and thunder produced by cumulonimbus clouds, usually producing gusty winds, heavy rain, and sometimes hail. Thunderstorms are usually short in duration (seldom more than two hours). They have three stages:
• The developing stage is marked by a cumulus cloud that is being pushed upward by a rising column of air (updraft). The cumulus cloud soon looks like a tower. There is little to no rain during this stage but occasional lightning. The developing stage lasts about 10 minutes. 289
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• In the mature stage, the updraft continues to feed the storm, precipitation begins to fall, and a downdraft begins (a column of air pushing downward). When the downdraft and rain-cooled air spread out along the ground, they form a line of gusty winds. The mature stage is the most likely time for hail, heavy rain, frequent lightning, strong winds, and tornadoes.
• Eventually, a large amount of precipitation is produced and the updraft is overcome by the downdraft, beginning the dissipating stage. At the ground, the gusty winds move out a long distance from the storm and cut off the warm moist air that was feeding the thunderstorm.

According to the American Meteorological Society Glossary of Meteorology, thunderstorms are reported as light, medium, or heavy according to the following characteristics:
• Nature of the lightning and thunder
• Type and intensity of the precipitation
• Speed and gustiness of the wind
• Appearance of the clouds
• Effect on surface temperature.

A thunderstorm is classified as “severe” when it contains one or more of the following: hail with a diameter of three-quarter inch or greater, winds gusting in excess of 50 knots (57.5 mph), or tornado.

Atmospheric Rivers
An atmospheric river is a common weather pattern that brings southwest winds and heavy rain to California.

Atmospheric rivers are long, narrow regions in the atmosphere that transport water vapor carried away from the tropics. These columns of vapor move with the weather, carrying large amounts of water vapor and strong winds.

When they make landfall, they often release the water vapor in the form of heavy rain or snow.

Lightning
Lightning is an electrical discharge that results from the buildup of positive and negative charges within a thunderstorm. When the buildup becomes strong enough, lightning appears as a “bolt.” This flash of light usually occurs within the clouds or between the clouds and the ground. A bolt of lightning reaches temperatures approaching 50,000ºF instantaneously. The rapid heating and cooling of air near the lightning causes thunder.

Lightning is a major threat during a thunderstorm. In the United States, between 1989 and 2018, lightning killed an average of 43 people per year (National Weather Service 2019).

Hail
Hail occurs when updrafts in thunderstorms carry raindrops upward into extremely cold areas of the atmosphere where they freeze into ice. Super-cooled water may accumulate on frozen particles near the back-side of a storm as they are pushed forward across and above the updraft by the prevailing winds near the top of the storm.

Eventually, the hailstones encounter downdraft air and fall to the ground. Hailstones can begin to melt and then re-freeze together, forming large and very irregularly shaped hail. 290

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13.1.2 Extreme Heat
Extreme heat is defined as temperatures that hover 10 ºF or more above the average high temperatures for a region for several days or weeks. Extreme heat events can lead to an increase in heat-related illnesses and deaths, cause drought, and impact water supplies. Heat waves do not strike victims immediately, but their cumulative effects slowly cause harm to vulnerable populations. Older adults, children, and sick or overweight individuals are at greater risk from extreme heat. Such events do not typically impact buildings; however, losses may be associated with the urban heat island effect and overheating of heating, ventilation, and air conditioning systems.

Extreme heat is the primary weather-related cause of death in the United States. Excessive heat claims over 100 lives each year in this country. In a 30-year record of weather fatalities across the nation (1990-2019), excessive heat claimed more lives each year than floods, lightning, tornadoes, and hurricanes (Erdman 2022).

According to the California Climate Adaptation Strategy, heat waves have claimed more lives in California than all other declared disaster events combined. Despite this history, in a span of 60 years, only four heat emergencies (August 14, 2020; September 2, 2020; June 16, 2021; July 9, 2021) were proclaimed in California at the state level and none were proclaimed at a federal level.

The heat index is what the temperature feels like to the human body when relative humidity is combined with the air temperature. When the body gets too hot, it begins to perspire or sweat to cool itself off. If the perspiration is not able to evaporate, the body cannot regulate its temperature. When atmospheric moisture content (humidity) is high, the rate of evaporation from the body decreases, and the body feels warmer. Figure 13-1 shows the heat index used by the National Weather Service (National Weather Service n.d.).

Figure 13-1. National Weather Service Heat Index
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13.1.3 Damaging Winds
Straight-Line Winds
Straight-line wind is a general term used to describe winds that have no rotation (i.e., are not tornadoes).

Damaging straight-line winds are those that exceed 50 to 60 mph. The Beaufort wind chart (Table 13-1) provides terminology and a description of potential impacts at different levels.

Table 13-1. Beaufort Wind Chart
Beaufort
Number
Range
(mph) Terminology Description
0 0 Calm Calm. Smoke rises vertically.
1 1-3 Light air Wind motion visible in smoke.
2 4-7 Light breeze Wind felt on exposed skin. Leaves rustle. 3 8-12 Gentle breeze Leaves and smaller twigs in constant motion. 4 13-18 Moderate breeze Dust and loose paper are raised. Small branches begin to move. 5 19-24 Fresh breeze Smaller trees sway
6 25-31 Strong breeze Large branches in motion. Whistling heard in overhead wires. Umbrella use is difficult. 7 32-38 Near gale Whole trees in motion. Some difficulty when walking into the wind. 8 39-46 Gale Twigs broken from trees. Cars veer on road. 9 47-54 Sever gale Light structure damage.
10 55-63 Storm Trees uprooted. Considerable structural damage. 11 64-73 Violent storm Widespread structural damage.
12 74-95 Hurricane Considerable and widespread damage to structures.

Source: (NWS n.d.)
Public Safety Power Shutoff Events
High winds can uproot trees, blow branches onto power lines or create sparks if power lines contact one another.

When this occurs in combination with extreme heat and low humidity that dry out vegetation, it poses increased risks of wildfire. In 2012, the California Public Utilities Commission ruled that California Public Utilities Code gives electric utilities authority to shut off electric power to protect public safety by reducing the potential to ignite wildfires (California Public Utilities Commission 2021). Such shutoffs are referred to as public safety power shutoff events. Given the long, connected nature of power supply systems, a shutoff event targeted to a small at-risk area can affect a larger area outside the risk zone. The duration of a shutoff is tied directly to the severe weather that triggers it; the shutoff typically ends within 24 hours after the severe weather has passed (Pacific Gas & Electric 2022).

13.1.4 Space Weather
Space weather refers to variations in the space environment between the sun and earth. It includes phenomena that impact systems and technologies in orbit and on earth. Space weather can occur anywhere from the surface of the sun to the surface of the earth. As a space weather storm leaves the sun, it passes through the sun’s corona and into the solar wind. When it reaches earth, it energizes earth’s magnetosphere and accelerates electrons and protons down to earth’s magnetic field lines where they collide with the atmosphere and ionosphere, particularly at high latitudes. Each component of space weather impacts a different technology. Figure 13-2 illustrates several types of space weather phenomena.
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Figure 13-2. Space Weather Phenomena
A solar flare occurs when magnetic energy that has built up in the solar atmosphere is suddenly released. The flare ejects clouds of electrons, ions, and atoms through the corona of the sun into space. These clouds typically reach earth a day or two after the event. Solar flares last from minutes to hours. Radiation is emitted across virtually the entire electromagnetic spectrum, from radio waves at the long wavelength end, through optical emission to X-rays and gamma rays at the short wavelength end ( (National Aeronautics and Space Administration 2016)). Solar flares only impact the earth when they occur on the side of the sun that faces the earth (National Aeronautics and Space Administration 2016a). If the energy from a solar flare reaches the earth, it has the potential to affect global positioning system (GPS) signals, television and radio transmissions, and telecommunications.

13.1.5 Secondary Hazards
The most significant secondary hazards associated with severe weather are floods and landslides. Heavy rain can overwhelm natural and man-made drainage systems, causing overflow and property destruction. Landslides occur when the soil on slopes becomes oversaturated and fails.

13.2 HAZARD PROFILE

13.2.1 Past Events
Sources that provide historical information regarding previous occurrences and losses associated with severe weather events in Alameda County and the planning area include FEMA, NWS, and NOAA NCEI. Between 1970 and March 2022, Alameda County was included in 12 FEMA disaster declarations for severe storms, severe 293
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winter storms, mudslides, landslides and flooding. Impacts on the planning area were not identified in the sources reviewed.

According to NOAA NCEI, between 1996 and March 2022, no extreme heat nor tornado events were recorded in Alameda County. Three hail events occurred in the county, but not in the Tri-Valley planning area. Alameda County recorded 30 high wind events in this timeframe with wind magnitude ranging between 44 knots and 96 knots, 39 strong wind events with wind magnitude between 30 knots and 48 knots, and five thunderstorm wind events. Table 13-2 lists known severe weather events that impacted the planning area between 1970 and April 2017, along with solar flare events that occurred in North America.

Table 13-2. Severe Weather Events in the Tri-Valley Planning Area Event Date Event Type
FEMA
Declaration Location Description
October 24,
2021
Atmospheric
River, Flood,
Heavy Rain
N/A Alameda County An atmospheric river system brought heavy rain, urban and small stream flooding, strong winds, and high surf to the region. Area streams rose rapidly. Multiple flood advisories and warnings were issued. Several downed trees were reported, along with wind gusts of 40 to 50 mph at lower elevations and 60 to 80 mph in the hills.

One station in Alameda County reported a wind gust of 92 mph.

February 20,
2017
Atmospheric
River, Heavy
Rain, Flash Flood
N/A Alameda County An atmospheric river brought heavy rain, causing widespread flooding, debris flows, accidents, and overtopping of reservoir spillways. SR 84 completely closed in both directions due to Alameda Creek flooding between Mission in Fremont to Main Street in Sunol
February 7,
2017
Atmospheric
River
DR- 4308 Alameda
County, planning
area, Bay Area
An atmospheric river produced widespread roadway flooding, debris flows, strong winds, and overtopping of reservoir spillways in the Bay Area. Pleasanton recorded 2.45 inches of rain on Feb. 20.

January 20,
2017
Atmospheric
River
DR- 4305 Alameda
County, planning
area, Bay Area
January 10,
2017
Atmospheric
River
DR- 4301 Alameda
County, planning
area, Bay Area
An atmospheric river produced widespread roadway flooding, debris flows, and strong winds in the Bay Area. Pleasanton recorded

2.15 inches of rain on Jan 10.

December 10
– 11, 2014
Heavy Rains and
High Winds
N/A Alameda
County, planning
area, and Bay
Area
An atmospheric river brought heavy rains and gusty winds to the Bay Area for several days. Rainfall of 1.5 to 2 inches an hour was reported. A flash flood warning was issued for Dublin, Livermore and Pleasanton. Wind gusts were recorded up to 83 mph. Rainfall totals ranged from 5.78 to 7.24 inches. Power outages occurred across the Bay Area. Total rainfall in Pleasanton was 3.27 inches.

December
2006
Geomagnetic
Storms and Solar
Flares
N/A United States This event disabled GPS signal acquisition over the United States.

April 6-20,
2006
Heavy Rain and
Debris Flows
DR-1646 Alameda County
and planning
area
Storms brought heavy rain causing landslides, eroding hillsides and cracked pavement. Landslides or erosion on private properties spilled over onto county rights-of-way. Overall, the County had approximately $10 million in damage to county roadways.

December 17,
2005 –
January 12,
2006
Winter Storms
(Severe Storms,
Flood, Mudslides,
Landslides)
DR-1628 Alameda
County, planning
area, Bay Area
Damage estimates for the region were over $100 million. Storms were blamed for two deaths from falling trees, around 50 businesses declared damage, and three homes were nearly wiped out by mudslides.
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Event Date Event Type
FEMA
Declaration Location Description
October 2003 Space Weather
(“Halloween
Storms of 2003”)
N/A Parts of the
Europe and the
United States
Solar flares impacted satellite-based systems and communications.

A one-hour-long power outage resulted in Sweden. Aurorae were observed as far south as Texas.

December 28,
1996 – April 1,
1997
Severe Storms,
Flooding, Mud
and Landslides
DR-1155 48 counties
including
Alameda County
Over 12,000 people were evacuated in northern California. Levee breaks were reported across the Sacramento and San Joaquin Valleys. Over 23,000 homes and business, agricultural lands, bridges, and roads were damaged. The event caused eight deaths and $1.8 billion in damage.

March 13,
1989
Space Weather
Storm
N/A Quebec, Canada A space weather storm disrupted the hydroelectric power grid in Quebec, Canada. This system-wide outage lasted for 9 hours and left 6 million people without power.

February 12 –
March 10,
1986
Severe Storms &
Flooding
DR-758 Bay Area
including
Alameda County
This event damaged over 12,000 homes, destroyed over 1,300 homes, and caused 13 deaths and 67 injuries in California. Damage totaled over $407.5 million.

January 3 – 5,
1982
Landslides,
Floods, and
Marine Effects
DR-651 Bay Area
including
Alameda County
A major storm caused widespread and catastrophic landslide damage throughout the Bay Area, resulting in numerous deaths and over $60 million in direct costs. In Alameda County, damage was concentrated in Oakland, Piedmont, and Berkeley. The County had approximately $3.5 million in damage.

February 10,
1970
Severe Storms &
Flooding
DR-283 Bay Area
including
Alameda County
Heavy winds, storms and flooding impacted the Bay Area, including Alameda County. Impacted areas had over $27 million in damage.

Source: FEMA, 2017b; NOAA NCEI, 2022

13.2.2 Location
All severe weather conditions profiled in this chapter have the potential to happen anywhere in the planning area.

No location mapping is currently available.

13.2.3 Frequency
The planning area can expect to experience exposure to and adverse impacts from severe weather events almost annually.

13.2.4 Severity
The most common problems associated with the severe weather conditions profiled in this assessment are immobility and loss of utilities. Fatalities are uncommon, but can occur. Roads may become impassable due to flooding, downed trees, or a landslide. Power lines may be downed due to high winds, and services such as water or phone may not be able to operate without power. Lightning can cause severe damage and injury. Physical damage to homes and facilities can be caused by wind or flooding.

Atmospheric rivers or heavy precipitation can have significant impacts, including crop damage, soil erosion, and increased risk of flood. These events can drop up to 12 inches of rain over a few days and cause widespread flooding and disruption to road and air travel. Stormwater runoff from heavy rains can also impair water quality by washing pollutants into water bodies. Thunderstorms carry the same risks as heavy precipitation events, and depending on the type of storm, they can also result in tornados, lightning, and heavy winds, increasing risk of injury and property damage (Keller and Blodgett 2008).
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Lightning severity is typically associated with both property damage and life safety (injuries and fatalities). The number of reported injuries from lightning is likely to be low, but planning area infrastructure losses can be up to thousands of dollars each year. Lightning also is associated with wildfire ignitions in the planning area.

An indicator of the potential severity of extreme heat is the number of heat advisories issued for the planning area by the National Weather Service. Figure 13-3 shows the annual number of heat advisories in Alameda and Contra Costa Counties since 2006.

Source: (Times Record News 2023)
Figure 13-3. Annual Number of Heat Advisories in Alameda and Contra Costa Counties Since 2006 Windstorms can be a frequent problem in the planning area and have been known to cause damage to utilities.

Strong, hot, dry offshore winds locally known as “diablo winds” can be particularly dangerous. These winds can occur at any time of year, but are especially dangerous in summer and fall when vegetation is at its driest. The wind speed given in wind warnings issued by the NWS is for a one-minute average; gusts may be 25 to 30 percent higher. The FEMA Winds Zones of the United States map (Figure 13-4) indicates the strength of windstorms in the United States and the general location of the most wind activity, based on 40 years of tornado data and 100 years of hurricane data collected by FEMA. The planning area, along with most of the Western United States, is in Wind Zone I, where wind speeds can reach up to 130 mph.

Solar flares can lead to long-term power grid outages. Moderate solar storms have affected transformers as they are not very resilient to long electromagnetic pulses (Global Resilience Network 2016). Recent events impacting the United States have disrupted the power grid, shut down satellites and air traffic precision navigation, and disabled GPS signals. Power outages induced by space weather can be life-threatening to those dependent on electricity for life support.
0 5
10 15
20 25
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 296

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Source: (National Institutes of Standards and Technology 2011) Figure 13-4. Wind Zones in the United States

13.2.5 Warning Time
Meteorologists can often predict the likelihood of a severe weather event. This can give several days of warning time. However, meteorologists cannot predict the exact time of onset or severity of the storm. Some storms may come on more quickly and have only a few hours of warning time. The San Francisco Bay Area Weather Forecast Office of the NWS monitors weather stations and issues watches and warnings when appropriate to alert government agencies and the public of possible or impending weather events. The watches and warnings are broadcast over NOAA weather radio and are forwarded to the local media for retransmission using the Emergency Alert System.

Space weather prediction in the United States is provided primarily by the Space Weather Prediction Center and the U.S. Air Force’s Weather Agency. The Space Weather Prediction Center draws on a variety of data sources, both space- and ground-based, to provide forecasts, watches, warnings, alerts, and summaries to civilian and commercial users.

13.3 EXPOSURE AND VULNERABILITY
A lack of clearly defined extent mapping for the severe weather conditions profiled in this chapter prevents a detailed analysis of exposure and vulnerability. However, it can be assumed that the entire planning area is exposed to some extent to all severe weather conditions profiled. Certain areas are more exposed due to geographic location and local weather patterns.
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13.3.1 Population
All people in the planning area are exposed to some degree to the severe weather hazard. The most common problems associated with severe weather events are immobility and loss of utilities. Vulnerable populations are the elderly, low income or linguistically isolated populations, people with life-threatening illnesses, and residents living in areas that are isolated from major roads. Power outages can be life threatening to those dependent on electricity for life support, making the local at-risk senior community and individuals with disabilities in the cities of Dublin, Livermore, and Pleasanton and those served by DSRSD especially vulnerable. These populations face isolation and exposure during severe weather events and could suffer more secondary effects of the hazard. Those experiencing homelessness who lack adequate shelter may be directly exposed to severe weather, leading to the destruction of temporary shelter, heat stroke, hypothermia, or illness from this exposure.

Populations living at higher elevations with large stands of trees or power lines may be more susceptible to wind damage and black out. The most common impacts of specific weather event types on people are as follows:
• Severe Storms—Nationally, lightning is one of the leading causes of weather-related fatalities, though lightning strikes are less common in the west than in other areas of the country. The majority of injuries and deaths associated with lightning occur when people are outdoors; however, almost one-third of lightning-related injuries occur indoors. Males are five times more likely than females to be struck by lightning and people between the ages of 15 and 34 account for 41 percent of all lightning strike victims. • Damaging Winds—Debris carried by extreme winds and trees felled by gusty conditions can contribute directly to loss of life as well as increase the vulnerability of people by damaging buildings where people take shelter. Utility lines brought down by winds have been known to cause fires and create the possibility of lethal electric shock.
• Extreme Heat—Individuals with physical or mobility constraints, cognitive impairments, economic constraints, or social isolation are typically at greater risk to the adverse effects of extreme heat. Some medical conditions, such as heat stroke, are directly attributable to extreme heat, while others may be exacerbated by it, resulting in medical emergencies.
• Space Weather —The sun’s activities cause extreme space weather events that can affect the City’s population, mainly by power black-out events

13.3.2 Property
Most of the buildings within the census tracts that define the planning area are residential. Older structures were built without the influence of a structural building code that would mitigate the severe weather conditions profiled in this assessment. All of these buildings are considered to be exposed to the severe weather hazard, but structures in poor condition or in particularly vulnerable locations (located on hilltops or exposed open areas) may risk the most damage. The frequency and degree of damage will depend on specific locations.

Loss estimations for the severe weather hazard are not based on damage functions, because no such damage functions have been generated. Instead, loss estimates were developed representing 10 percent, 30 percent, and 50 percent of the assessed value of exposed structures. Figure 13-5 lists the loss estimates. These estimates allow emergency managers to select a range of potential economic impact based on an assessment of the percent of damage to the general building stock. Damage in excess of 50 percent is considered to be substantial by most building codes and typically requires total reconstruction of the structure. 298

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Figure 13-5. Loss Estimates for Severe Weather

13.3.3 Critical Facilities
All critical facilities are vulnerable during severe weather events, especially those that lack backup power generation capabilities. When facilities supplying power to planning area land line telephone systems are frequently disrupted, significant issues arise with communication in the planning area. In addition, some facilities are particularly vulnerable to specific types of severe weather events:
• Thunderstorms—Facilities and transportation systems are vulnerable to disruption from secondary hazards such as flooding or landslides.
• Damaging Winds—Facilities near trees or power lines that are likely to fall are vulnerable. Roads and other transportation infrastructure could be blocked by downed trees or other debris. • Extreme Heat— Extreme heat is generally not a threat to damage critical facilities or infrastructure. • Space Weather— Extreme space weather events can degrade or damage critical infrastructures, which may result in direct or cascading failures across key services such as electric power, communications, water supply, healthcare, and transportation (National Science & Technology Council 2019).

13.3.4 Environment
The environment is highly exposed to severe weather events. Natural habitats such as streams and trees are exposed to the elements during a severe storm and risk major damage and destruction. Prolonged rains can saturate soils and lead to slope failure. Flooding events caused by severe weather can produce river channel migration or damage riparian habitat.

DSRSD, $1,462,900
DSRSD, $4,388,700
DSRSD, $7,314,500
DSRSD, $14,629,000
Dublin, $2,045,467,529
Dublin, $6,136,402,587
Dublin, $10,227,337,644
Dublin, $20,454,675,289
Livermore, $2,979,889,648
Livermore, $8,939,668,945
Livermore, $14,899,448,241
Livermore, $29,798,896,482
Pleasanton, $2,934,923,624
Pleasanton, $8,804,770,872
Pleasanton, $14,674,618,120
Pleasanton, $29,349,236,239
$0 $10,000,000,000 $20,000,000,000 $30,000,000,000 $40,000,000,000 Loss = 10% of
Total
Replacement
Value
Loss = 30% of
Total
Replacement
Value
Loss = 50% of
Total
Replacement
Value
Total
Replacement
Value
Loss Value
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13.4 FUTURE TRENDS IN DEVELOPMENT
All future development will be affected by severe storms. The ability to withstand impacts lies in sound land use practices and consistent enforcement of codes and regulations for new construction. The planning partners have adopted the International Building Code in response to California mandates. This code is equipped to deal with the impacts of severe weather events. Land use policies identified in general plans within the planning area also address many of the secondary impacts (flood and landslide) of the severe weather hazard. With these tools, the planning partners are well equipped to deal with future growth and the associated impacts of severe weather.

13.5 SCENARIO
Severe weather impacts can be significant, particularly when secondary hazards occur. A worst-case event would involve prolonged high winds during a winter storm caused by an atmospheric river event. Such an event would have both short-term and longer-term effects. Initially, schools and roads would be closed due to power outages caused by high winds and downed tree obstructions. Prolonged rain could produce flooding, overtopped culverts with ponded water on roads. Flooding and debris could further obstruct roads and bridges, further isolating residents.

13.6 ISSUES
Important issues associated with a severe weather in the planning area include the following:
• Older building stock in the planning area is built to low code standards. These structures could be highly vulnerable to severe weather events such as windstorms. • The cities may need to open cooling centers during extreme heat events. • Redundancy of power supply and communications equipment must be evaluated. • The capacity for backup power generation is limited.
• Dead or dying trees as a result of drought conditions are more susceptible to falling during severe storm events.
• Public education on dealing with the impacts of severe weather needs to continue to be provided so that citizens can be better informed and prepared for severe weather events. • Debris management (downed trees, etc.) must be addressed, because debris can impact the severity of severe weather events, requires coordination efforts, and may require additional funding. • The effects of climate change may result in an increase of heavy rain or more atmospheric storm events, and will likely lead to increased temperatures and changes in overall precipitation amounts. 300
14-1

14. WILDFIRE

14.1 GENERAL BACKGROUND
A wildfire is any uncontrolled fire occurring on undeveloped land that requires fire suppression. Wildfires can be ignited by lightning or by human activity such as smoking, campfires, equipment use, and arson. The potential for such fires is primarily influenced by the following factors:
• Fuel—Fuel may include living and dead vegetation on the ground, along the surface as brush and small trees, and above the ground in tree canopies. Lighter fuels such as grasses, leaves, and needles quickly expel moisture and burn rapidly, while heavier fuels such as tree branches, logs and trunks take longer to warm and ignite. Trees killed or defoliated by forest insects and diseases are more susceptible to wildfire. • Weather—Relevant weather conditions include temperature, relative humidity, wind speed and direction, cloud cover, precipitation amount and duration, and the stability of the atmosphere. Conditions are favorable for severe wildfires when the temperature is high, relative humidity is low, wind speed is increasing and coming from the east (inland), and there has been little or no precipitation. These conditions occur more frequently inland where temperatures are higher and fog is less prevalent. • Terrain—Topography includes slope and elevation. The topography of a region influences the amount and moisture of fuel; the impact of weather conditions such as temperature and wind; potential barriers to fire spread, such as highways and lakes; and elevation and slope of landforms (fire spreads more easily uphill than downhill).

14.1.1 Wildfire Hazard Mapping
Fire Hazard Severity Zones
The California Department of Forestry and Fire Protection (CAL FIRE) has modeled and mapped wildfire hazard zones using a computer model that designates moderate, high or very high fire hazard severity zones (FHSZ).

CAL FIRE classifies these zones based on how a fire would behave in a given area and the probability of flames and embers threatening buildings. Each area gets a score for flame length, embers, and the likelihood of the area burning. Scores of smaller areas are then averaged over larger zones that encompass them.

CAL FIRE’s maps these zones using a model that derives fire frequency from 50 years of fire data. The model considers the frequency of fire weather, ignition patterns, and expected rate-of spread. It accounts for flying ember production, which is the principal driver of the wildfire hazard in densely developed areas. A related concern in built-out areas is the relative density of vegetative fuels that can serve as sites for new spot fires and spread fire between structures. The model refines the zones to characterize fire exposure mechanisms that cause ignitions to structures.
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14.1.2 Wildfire Protection Responsibility in California Hundreds of local, state, and federal agencies have responsibility for wildfire protection in California. Often, two organizations share responsibility on the same parcel of land—one for wildfire protection, and the other for structural or “improvement” fire protection. To address wildfire jurisdictional responsibilities, the California state legislature adopted legislation establishing the following responsibility areas:
• Federal Responsibility Areas (FRAs)—FRAs are fire-prone wildland areas owned or managed by a federal agency (e.g., Forest Service, National Park Service, Bureau of Land Management, Fish and Wildlife Service, Department of Defense). Primary financial and rule-making jurisdictional authority rests with the federal land agency. In many instances, FRAs are interspersed with private land ownership or leases. Fire protection for developed private property is usually not the responsibility of the federal land management agency; structural protection responsibility is that of a local government agency. • State Responsibility Areas (SRAs)—SRAs are lands where CAL FIRE has legal and financial responsibility for wildfire protection and administers fire hazard classifications and building standard regulations. SRAs are defined as lands that meet the following criteria:
➢ Are county unincorporated areas
➢ Are not federally owned
➢ Have wildland vegetation cover rather than agricultural or ornamental plants ➢ Have watershed or range/forage value
➢ Have housing densities not exceeding three units per acre.

Where SRAs contain built environment or development, the responsibility for fire protection of those improvements (non-wildland) is that of a local government agency. • Local Responsibility Areas (LRAs)—LRAs include land in cities, cultivated agriculture lands, nonflammable areas in unincorporated areas, and lands that do not meet the criteria for SRA or FRA. LRA fire protection is typically provided by city fire departments, fire protection districts, and counties, or by CAL FIRE under contract to local governments. The Cities of Dublin, Livermore and Pleasanton are located in incorporated LRAs. LRAs may include flammable vegetation and areas where the financial and jurisdictional responsibility for improvement and wildfire protection is that of a local government agency.

State law requires local governments to update their general plan safety elements to recognize SRAs and “Very High” FHSZs. The safety element must include information and policies on unreasonable risk from fire. The state encourages integration among jurisdictions to enhance mitigation and prevention efforts.

14.1.3 Secondary Hazards
Secondary effects of wildfires can in some cases cause more damage than the fire itself. Wildfires strip slopes of vegetation, exposing them to greater amounts of runoff. This in turn can weaken soils and cause failures on slopes. Major landslides can occur several years after a wildfire. Most wildfires burn hot and for long durations that can bake soils, especially those high in clay content, thus increasing the imperviousness of the ground. This increases the runoff generated by storm events, thus increasing the chance of flooding.

14.2 HAZARD PROFILE

14.2.1 Local Climate Conditions Related to Wildfire
The planning area has a Mediterranean-like climate with no summer rains and potential high winds. Non-native and invasive weedy vegetation has replaced more fire resistant and ecologically stable native species in many 302

14. Wildfire
14-3
places. In addition, highly flammable homes are located in high fire hazard zones. “Red flag” weather in the planning area features strong, hot, dry offshore winds known as “diablo winds.” These winds carry extremely dry air at high velocity and can push a fire down or up a slope quickly. They can occur at any time of year but are especially dangerous in the driest months of summer and fall.

14.2.2 Past Events
Between 1954 and May 2022, Alameda County was included in two FEMA major disaster (DR) fire management assistance declarations (DR-919 Oakland Hills Fire in 1991 and DR-295 Buckingham Norfolk Fire in 1970) but neither of these affected the planning area. With drought conditions in recent years, wildfires have occurred near the planning area, though none have caused sufficient damage to trigger a state or federal disaster declaration.

Table 14-1 lists wildfires of over 10 acres recorded near the planning area in recent years (CAL FIRE 2023).

Table 14-1. Recent Fires Affecting Planning Area (Burning More Than 10 Acres) Start Date
Date
Contained
Acres
Burned Location
07/16/20 07/19/20 253 Near Tesla Road and McLaughlin Road, southeast of Livermore. 07/04/20 07/05/20 108 Near Sheridan Road, south of Sunol (which is just south of Pleasanton). 10/24/19 10/27/19 35 Near Mines Rd and Del Valle Rd, southeast of Livermore. 10/08/19 10/08/19 12 Near SR 84 and Little Valley Road in Sunol, south of Pleasanton. 09/02/19 09/02/19 11 Near Mines Road in Livermore.
08/31/19 08/31/19 19 Near eastbound 580 and North Flynn Road, east of Livermore. 08/21/19 08/21/19 139 Near Patterson Pass and Midway Road, east of Livermore. 08/09/19 08/12/19 240 Near Central Pkwy and Croak Rd, 4 miles east of Dublin. 06/21/19 06/24/19 30 Near Grant Line Rd and Mountain House Rd, east of Livermore. 11/14/18 01/04/19 20 Near Vallecitos Road and Little Valley, south of Livermore. 07/08/18 01/04/19 640 Near I-580 and Grantline Rd, east of Livermore. 07/25/18 01/04/19 34 Near Patterson Pass Road and Midway Rd, east of Livermore. 05/14/18 01/04/19 12 Near Grant Line Road and I-580, east of Livermore. 10/17/17 01/09/18 116 Near Fallon Road 3 miles East of Dublin. 08/22/17 01/09/18 200 Near Range Road and Cromwell Avenue, Camp Parks Dublin, National Guard Reserve Forces Training Center.
06/25/16 06/26/16 211 In the Altamont Pass, 10 miles east of Livermore. 08/19/15 08/22/15 2,700 Off Tesla Road near Corral Hollow between Livermore and Tracy. This fire took four days to contain with 18 fire personnel and five fire engines.
06/25/15 06/25/15 53 Near Tesla Road, southeast of Livermore. 10/04/13 10/04/13 150 Along Highland Road near Livermore. 07/06/13 07/06/13 38 Near Fallon Road and Camino Tassajara near Dublin. 06/08/13 06/08/13 240 Near Vasco Road and North Vasco Road, north of Livermore.

14.2.3 Location
Figure 14-1 shows the FHSZ mapping for the planning area. 303
Figure 14-1
304

14. Wildfire
14-5

14.2.1 Frequency
Wildfire frequency can be assessed through review of the percent of a given area that has been burned in previous wildfire events. Based on CAL FIRE records of fires, about 3 percent of the mapped wildfire risk zones in Alameda County burned in the 138-year period from 1878 to 2016 (see Table 14-2).

Table 14-2. Record of Fire in Alameda County
Area Burned, 1878 – 2016
FHSZ Category Total Area in Zone (acres) Acres Percent of Total Area Moderate 10,564 115 1.09%
High 9,455 498 5.26%
Very High 472 0 0.00%
Source: CAL FIRE, 2016

14.2.2 Severity
The largest wildfire in the Bay Area, and one of the worst wildfires in the United States, occurred in 1991 in the Oakland Hills of Alameda County. The fire resulted in $1.7 billion in losses and received a FEMA disaster declaration. The fire spread across 1,520 acres, destroyed 3,354 homes and 456 apartments, injured 150 people and took the lives of 25 people (Alameda County 2021). There are no recorded incidents of loss of life from wildfires in the planning area.

Potential losses from wildfire include human life, structures and other improvements, and natural resources. There are no recorded incidents of loss of life from wildfires within the planning area. Given the immediate response times to reported fires, the likelihood of injuries and casualties is minimal.

Smoke and air pollution from wildfires can be a health hazard, especially for children, the elderly and those with respiratory and cardiovascular diseases. First responders are exposed to dangers from the initial incident and aftereffects from smoke inhalation and heat stroke. Public health impacts associated with wildfire include difficulty in breathing, odor, and reduction in visibility.

14.2.3 Warning Time
Wildfires are often caused by humans, intentionally or accidentally. There is no way to predict when one might break out. Since fireworks often cause brush fires, extra diligence is warranted around the Fourth of July when the use of fireworks is highest. Dry seasons and droughts are factors that greatly increase fire likelihood. Dry lightning may trigger wildfires. Severe weather can be predicted, so special attention can be paid during weather events that may include lightning. Reliable National Weather Service lightning warnings are available on average 24 to 48 hours prior to a significant electrical storm
If a fire does break out and spread rapidly, residents may need to evacuate within days or hours. Once a fire has started, fire alerting is reasonably rapid in most cases. The rapid spread of cellular and two-way radio communications in recent years has further contributed to a significant improvement in warning time. .
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14.3 EXPOSURE

14.3.1 Population
Population exposed to the wildfire hazard was estimated using the structure count of buildings in each mapped FHSZ and multiplying by the estimated average population per household. Figure 14-2 shows the estimated population for each planning area city living in the moderate, high, and very high FHSZs, compared to total city population. Figure 14-3 shows results for the entire planning area. Population served by DSRSD cannot be mapped to determine its exposure to the wildfire hazard.

Figure 14-2. Population Exposed to Wildfire Hazard and Total City Population, by Jurisdiction Figure 14-3. Total Planning Area Population Exposed to Wildfire Hazard 14,692
(20.1% of Total)
843
(1.0% of Total)
242
(0.3% of Total)
30 (0.0% of Total)
3 (0.0% of Total) 239
0 (0.3% of Total)
(0.0% of Total) 0
(0.0% of Total) 2,216
(2.9% of Total)
72,932
86,149
77,609
0 20,000
40,000
60,000
80,000
100,000
Dublin Livermore Pleasanton
Population
Exposed Population, Moderate FHSZ
Exposed Population, High FHSZ
Exposed Population, Very High FHSZ
Total City Population
15,777
(6.7% of Total) 272
(0.1% of Total)
2,216
(0.9% of Total)
236,690
0 50,000
100,000
150,000
200,000
250,000
Exposed Population, Moderate
FHSZ
Exposed Population, High
FHSZ
Exposed Population, Very High
FHSZ
Total Planning Area Population
Population
306

14. Wildfire
14-7

14.3.2 Property
The estimated value of planning area buildings within the moderate, high, and very high FHSZs is shown in Figure 14-4 through Figure 14-6. Figure 14-7 shows the estimated exposed total value as a percentage of the total replacement value in each city and in the overall planning area. The numbers of structures in each FHSZ, by occupancy class, are shown in Figure 14-8 through Figure 14-10.

Figure 14-4. Number and Exposed Value of Buildings in the Moderate FHSZ Figure 14-5. Number and Exposed Value of Buildings in the High FHSZ $0
$1,435,470,257
$164,887,580 $56,268,823
$0
$745,075,606
$121,540,389 $36,298,468
Total Exposed Value
$0
(0 Buildings)
Total Exposed Value
$2,180,545,864
(2,961 Buildings)
Total Exposed Value
$286,427,970
(305 Buildings)
(77 Buildings), Total
Exposed Value,
$92,567,291
$0
$1,000,000,000
$2,000,000,000
$3,000,000,000
$4,000,000,000
$5,000,000,000
DSRSD Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value
$5,994,000
$3,010,029
$12,094,330
$41,633,433
0 $1,505,014
$17,835,563
$21,623,464 Total Exposed Value
$599,400
(1 Buildings)
Total Exposed Value
$4,515,043
(6 Buildings)
Total Exposed Value
$29,929,893
(4 Buildings)
(69 Buildings), Total
Exposed Value,
$63,256,897
$0
$10,000,000
$20,000,000
$30,000,000
$40,000,000
$50,000,000
$60,000,000
$70,000,000
DSRSD Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value
307
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Figure 14-6. Number and Exposed Value of Buildings in the Very High FHSZ Figure 14-7. Total Value in FHSZs as Percent of Total Replacement Value, by Jurisdiction $0 $0 $0
$362,400,688
$0 $0 $0
Total Exposed Value $181,896,098
$0
(0 Buildings)
Total Exposed Value
$0
(0 Buildings)
Total Exposed Value
$0
(0 Buildings)
(626 Buildings), Total
Exposed Value,
$544,296,786
$0
$200,000,000
$400,000,000
$600,000,000
$800,000,000
$1,000,000,000
DSRSD Dublin Livermore Pleasanton
Exposed Value
Exposed Structure Value
Exposed Contents Value
DSRSD, 0%
DSRSD, 3%
DSRSD, 0%
Dublin, 10.7%
Dublin, 0.0%
Dublin, 0.0%
Livermore, 1.0%
Livermore, 0.1%
Livermore, 0.0%
Pleasanton, 0.3%
Pleasanton, 0.2%
Pleasanton, 1.9%
0% 20% 40% 60% 80% 100%
Moderate FHSZ
High FHSZ
Very High FHSZ
Exposed Value as % of Total City or Area Replacement Value 308

14. Wildfire
14-9
Figure 14-8. Structures in the Moderate FHSZ, by Jurisdiction and Occupancy Class Figure 14-9. Structures in the High FHSZ, by Jurisdiction and Occupancy Class Residential, 2,931
Residential, 276
Residential, 68
Commercial, 1
Commercial, 5
Commercial, 9
Industrial, 8
Industrial, 0
Industrial, 0
Agriculture, 6
Agriculture, 0
Agriculture, 0
Religion, 0
Religion, 0
Religion, 0
Government, 1
Government, 0
Government, 0
Education, 14
Education, 24
Education, 0
Dublin
Livermore
Pleasanton
0 500 1,000 1,500 2,000 2,500 3,000 3,500
Number of Structures in the FHSZ
CITIES
Residential, 3,275
Commercial, 15
Industrial, 8
Agriculture, 6
Religion, 0
Government, 1
Education, 38
0 500 1,000 1,500 2,000 2,500 3,000 3,500
Number of Structures in the FHSZ

PLANNING AREA TOTAL
Residential, 6
Residential, 1
Residential, 67
Commercial, 0
Commercial, 0
Commercial, 2
Industrial, 0
Industrial, 0
Industrial, 0
Agriculture, 0
Agriculture, 0
Agriculture, 0
Religion, 0
Religion, 0
Religion, 0
Government, 0
Government, 0
Government, 0
Education, 0
Education, 3
Education, 0
Dublin
Livermore
Pleasanton
0 20 40 60 80
Number of Structures in the FHSZ
CITIES
Residential, 74
Commercial, 2
Industrial, 0
Agriculture, 0
Religion, 0
Government, 0
Education, 3
0 20 40 60 80
Number of Structures in the FHSZ

PLANNING AREA TOTAL
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Figure 14-10. Structures in the Very High FHSZ, by Jurisdiction and Occupancy Class

14.3.3 Critical Facilities
Estimates of critical facilities in each FHSZ are summarized in Figure 14-11. The total count of critical facilities in high or very high fire hazard severity zones (11) represents 1 percent of the planning area total of 1,161.

14.3.4 Environment
All natural resources and habitats in mapped FHSZs are exposed to the risk of wildfire.

14.4 VULNERABILITY
Structures, above-ground infrastructure, critical facilities and natural environments are all vulnerable to the wildfire hazard. There is currently no validated damage function available to support wildfire mitigation planning.

Except as discussed in this section, vulnerable populations, property, infrastructure and environment are assumed to be the same as described in the section on exposure.

Residential, 0
Residential, 0
Residential, 622
Commercial, 0
Commercial, 0
Commercial, 3
Industrial, 0
Industrial, 0
Industrial, 0
Agriculture, 0
Agriculture, 0
Agriculture, 0
Religion, 0
Religion, 0
Religion, 0
Government, 0
Government, 0
Government, 1
Education, 0
Education, 0
Education, 0
Dublin
Livermore
Pleasanton
0 200 400 600 800
Number of Structures in the FHSZ
CITIES
Residential, 622
Commercial, 3
Industrial, 0
Agriculture, 0
Religion, 0
Government, 1
Education, 0
0 100 200 300 400 500 600 700
Number of Structures in the FHSZ

PLANNING AREA TOTAL
310

14. Wildfire
14-11
Figure 14-11. Critical Facilities in the High or Very High FHSZ

14.4.1 Population
Many communities and populations are especially vulnerable to wildfires, including low-income communities, migrant populations, populations whose primary language is not English, indigenous populations, communities of older adults, and those with respiratory and other health concerns. The local senior community and individuals within the cities of Dublin, Livermore, and Pleasanton and those served by DSRSD are especially vulnerable to respiratory issues in the event of reduced air quality following wildfire. Members of immigrant communities may be concerned about impacts to their immigration status and not seek help. The homeless population may also be affected with their exposure to smoke or airborne particulates, especially if no shelter or evacuation center has been open.

When a wildfire impacts an area with high rents where multiple families live in one structure, it may be difficult for those not listed on the lease to prove that they were affected by the fire; this could result in a lack of access to services. Additionally, fires quickly increase housing prices and rent prices, further displacing people already affected by the fire. Homelessness may increase as a result of wildfire events.

Communications, 0
Communications, 0
Communications, 0
Communications, 0
Energy, 0
Energy, 0
Energy, 0
Energy, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 0
Food, Water, Shelter, 10
Food, Water, Shelter, 1
Hazardous Material, 0
Hazardous Material, 0
Hazardous Material, 0
Hazardous Material, 0
Health & Medical, 0
Health & Medical, 0
Health & Medical, 0
Health & Medical, 0
Safety & Security, 0
Safety & Security, 0
Safety & Security, 0
Safety & Security, 0
Transportation, 0
Transportation, 0
Transportation, 0
Transportation, 0
Dublin
Livermore
Pleasanton
DSRSD
0 5 10 15 20
Number of Critical Facilities in the Hazard Zone