Attachment G - FEIR Appendix A - EIR Comment Letters — Pacifica City Council, June 25, 2022 (part 2 of 10)

Hillside and Coastal Development
“…ensure that new development does not detract from the visual qualities of Pacifica’s hillsides and visually prominent ridgelines
Scenic and Visual Amenities of the Coastal Zone
Protect the City’s irreplaceable scenic and visual amenities in the Coastal Zone by protecting landforms, vegetation, special communities and important viewsheds.

Scenic Routes
• Views from Scenic Routes. Ensure that designated viewsheds from Highway 1 and Sharp Park Road are preserved and enhanced. These views are an essential part of Pacifica’s identity.

DEIR 3.9 Visual Resources
“Protect the City’s irreplaceable scenic and visual amenities.” ‘…protect important views from public areas…” “the scenic quality of ridgelines…” CD-G-7 Views from Scenic Routes - (repeats page 2-25)
CD-I-26 Roadway Design. Ensure that any proposed new roads or modifications to existing roads which traverse scenic areas minimize visual impacts to views from Scenic Routes.
>> Support the above statements by designating and showing Montara and San Pedro Mountains and foothills on the map as a designated viewshed from Pacifica State Beach, Aramai Point and Highway 1.

Conservation Element
>> ADD: Grassland/Prairie. Conserve and protect remnant grassland/prairie for its value as a carbon sink.

ES-I-21 Shopping Center Upgrades.
>>Support upgrading existing centers to include affordable housing.

Pacifica Historic Context
>> Change first paragraph: In 1769, an expedition led by Gaspar de Portola, governor of the Spanish territory covering California, followed an Ohlone trail over the Montara/San Pedro Mountain saddle (later the Old Coast Road) to San Pedro Valley where they camped. From the valley, scouts discovered San Francisco Bay from a atop Sweeney Ridge.

Historic Resources
Nationally and State-Listed Resources
>> Update for 2019 completion and opening of new Sanchez Adobe visitors’ center.

3.7 Biological Resources
Plant Communities
1990 and 1992 source reports are out-of-date.
>> Replace “Annual” Grasslands with “Grassland/Prairie” >> Include common native and special species plants
Coastal Bluff Scrub (p. 3.7-6)
>> ACKNOWLEDGE 30 YEARS OF DUNE RESTORATION AT Pacifica State Beach.

Non-native iceplant (Carpobrotus edulis) New Zealand spinach (Tetragonia tetragonioides) have been virtually eradicated and replaced with appropriate natives grown and planted by volunteers.

Abronia latifolium
Achillea millefolium
Agoseris apargioides var. apargioides
Ambrosia chamissonis
Armeria maritima ssp. californica
Artemisia californica
Artemisia douglasiana
Artemisia pycnocephala
Atriplex leucophylla
Baccharis pilularis ssp. pilularis
Calystegia soldanella
Camissoniopsis cheiranthifolia ssp.
cheiranthifolia
Castilleja wightii
Distichlis spicata
Dudleya farinosa / hybrids?
Elymus mollis ssp. Mollis
Ericameria ericoides
Erigeron glaucus
Eriogonum latifolium
Eriophyllum staechadifolium
Eryngium armatum
Eschscholzia californica var maritima
Fragaria chiloensis
Grindelia stricta var. platyphylla
Lupinus arboreus
Lupinus chamissonis
Oenothera elata ssp. hookeri
Poa douglasii
Polygonum paronychia
Spurgularia macrotheca
Symphiotrichum chilense
Tanacetum bipinnatum
p. 3.7-11
>> The brackish water marsh at the north end of Pacifica State Beach was severely impacted by the widening of State Highway 1 and now contains only willows where saltmarsh common yellowthroats can be heard.. p. 3.7-14 Beach/Intertidal
>>Add Snowy Plovers, Sanderlings, Willits, Whimbrels
>> ADD: Pacifica State Beach in the 1970s hosted nesting Western Snowy Plovers, a Federally listed threatened species. Since 2003 volunteers have regularly surveyed and monitored the plovers and have seen only wintering plovers in declining numbers. ESHA is required on the north half of the beach where plovers roost and feed.
p. 3.7-18
Environmentally Sensitive Habitat Areas (ESHA)
Environmentally Sensitive Habitat Areas (ESHA) are defined by the California Coastal Act[1] as “any area in which plant or animal life or their habitats are either rare or especially valuable because of their special nature or role in an ecosystem and which could be easily disturbed or degraded by human activities and developments” (California Public Resources Code Section 30107.5).

Figure 3.7-3 Potentially Sensitive and Critical Habitat Area (AND Figure 7-3 Potentially Sensitive Habitat Area)
>> ESHA is required on the north half of the beach where plovers roost and feed on amphipods and kelp flies.

Page 3 ends

>> ADD: Pacifica State Beach, in the 1970s hosted nesting Western Snowy Plovers, a Federally ESA designated threatened species and a State of California “species of special concern.” PSB is identified in the 2007 USWFS Pacific Coast Recovery Plan as Recovery Unit CA-48. Since 2003, volunteers have regularly monitored the plovers for USFWS surveys and have seen only wintering plovers whose numbers continue to decline. p. 3.7-32
>> ADD to Saltmarsh common yellowthroat: Also reported at small willow marsh at northern end of Pacifica State Beach and Lake Mathilde remnant east of Crespi Community Center.
p. 3.7-35
ADD: Western pond turtle (Actinemys marmorata). Ca species of special concern Observed basking at San Pedro Creek – (Margaret Goodale personal observation , spring, 2019) (ALSO reported from Laguna Salada) p. 3.7-39
>> With the completion of the tunnels, Hickman’s cinquefoil is no longer threatened by the Devil’s Slide Bypass highway project. Update. p. 3.7-53 Impact of the General Plan
ADD: Western Snowy Plover as a special status wildlife species and identify Pacifica State Beach as ESHA.
p. 3.7-56
CO-I-1 Creek Protection and Restoration
• “Enforcing restrictions on the planting of invasive species near creek areas; • Requiring minimum setbacks from the top of creek banks for development proposed adjacent to creeks, in keeping with City regulations and Best Management Practices.” >> Specify “restrictions” and “minimum seatbacks”
p 3.7-59
CO-I-37 Protection of … During Construction
>> ADD Western Pond Turtles
p. 3.7-6
>> ESTABLISH ROBUST Habitat Conservation Plans and Natural Community Conservation Plan
p. 3.7-61 (Impact of the General Plan)
“…and San Pedro Creek is very close to the San Pedro Site.” >> Clearly Identify and add DETAIL ABOUT THE ”SAN PEDRO SITE” CO-I-28 Protection of Environmentally Sensitive Habitat Area (ESHA). Protect all sensitive species with defined or potential habitat… CO-I-29 Verification of ESHA
>> Most endangered or threatened species have been listed due to habitat limitations from human encroachment. We CANNOT further limit their habitat. Remove the possibility of mitigation. Loss of habitat cannot be mitigated.
p. 3.7-64
CO-I-46 Shoreline Protection. Continue to prohibit new development requiring shoreline alterations.
>> Specify and clarify date of “existing structures” to be consistent with Coastal Act.

Thank you for your consideration,
Margaret Goodale
Naturalist and Educator, San Pedro Valley Park, Sanchez Historic Site, San Francisco's Randall Museum
Environmental Advocate
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Miscellaneous topics – Margaret Goodale
Wildfire danger
>>Please include the informative Figure 8-5 Fire Hazards and Public Safety Services document from the 2014 draft. The 2014 mapping is much more realistic and useful than simply showing fire danger stopping at the city boundary. Pacificans’ safety depends on accurate information.

Plan Pacifica DEIR - Public Review Draft - Interactive TOC - 2022-01-07.pdf

Page 2 ends

Scenic Routes
• Views from Scenic Routes. Ensure that designated viewsheds from Highway 1 and Sharp Park Road are preserved and enhanced. These views are an essential part of Pacifica’s identity.

DEIR 3.9 Visual Resources
“Protect the City’s irreplaceable scenic and visual amenities.” ‘…protect important views from public areas…” “the scenic quality of ridgelines…” CD-G-7 Views from Scenic Routes - (repeats page 2-25)
CD-I-26 Roadway Design. Ensure that any proposed new roads or modifications to existing roads which traverse scenic areas minimize visual impacts to views from Scenic Routes. >> Support the above statements by designating and showing Montara and San Pedro Mountains and foothills on the map as a designated viewshed from Pacifica State Beach, Aramai Point and Highway 1.

Conservation Element
>> ADD: Grassland/Prairie. Conserve and protect remnant grassland/prairie for its value as a carbon sink.

ES-I-21 Shopping Center Upgrades.
>>Support upgrading existing centers to include affordable housing.

Historic Resources
Nationally and State-Listed Resources
>> Update for 2019 completion and opening of new Sanchez Adobe visitors’ center.

Non-native iceplant (Carpobrotus edulis) New Zealand spinach (Tetragonia tetragonioides) have been virtually eradicated and replaced with appropriate natives grown and planted by volunteers.

Abronia latifolium
Achillea millefolium
Agoseris apargioides var. apargioides
Ambrosia chamissonis
Armeria maritima ssp. californica
Artemisia californica
Artemisia douglasiana
Artemisia pycnocephala
Atriplex leucophylla
Baccharis pilularis ssp. pilularis
Calystegia soldanella
Camissoniopsis cheiranthifolia ssp.
cheiranthifolia
Castilleja wightii
Distichlis spicata
Dudleya farinosa / hybrids?
Elymus mollis ssp. Mollis
Ericameria ericoides
Erigeron glaucus
Eriogonum latifolium
Eriophyllum staechadifolium
Eryngium armatum
Eschscholzia californica var maritima
Fragaria chiloensis
Grindelia stricta var. platyphylla
Lupinus arboreus
Lupinus chamissonis
Oenothera elata ssp. hookeri
Poa douglasii
Polygonum paronychia
Spurgularia macrotheca
Symphiotrichum chilense
Tanacetum bipinnatum
p. 3.7-11
>> The brackish water marsh at the north end of Pacifica State Beach was severely impacted by the widening of State Highway 1 and now contains only willows where saltmarsh common yellowthroats can be heard.. p. 3.7-14 Beach/Intertidal
>>Add Snowy Plovers, Sanderlings, Willits, Whimbrels
>> ADD: Pacifica State Beach in the 1970s hosted nesting Western Snowy Plovers, a Federally listed threatened species. Since 2003 volunteers have regularly surveyed and monitored the plovers and have seen only wintering plovers in declining numbers. ESHA is required on the north half of the beach where plovers roost and feed.
p. 3.7-18
Environmentally Sensitive Habitat Areas (ESHA)
Environmentally Sensitive Habitat Areas (ESHA) are defined by the California Coastal Act1 as “any area in which plant or animal life or their habitats are either rare or especially valuable because of their special nature or role 1 California Coastal Commission. California Coastal Act, Public Resources Code Division 20, 2009. in an ecosystem and which could be easily disturbed or degraded by human activities and developments” (California Public Resources Code Section 30107.5).

Page 3 ends

>> ADD: Pacifica State Beach, in the 1970s hosted nesting Western Snowy Plovers, a Federally ESA designated threatened species and a State of California “species of special concern.” PSB is identified in the 2007 USWFS Pacific Coast Recovery Plan as Recovery Unit CA-48. Since 2003, volunteers have regularly monitored the plovers for USFWS surveys and have seen only wintering plovers whose numbers continue to decline.
p. 3.7-32
>> ADD to Saltmarsh common yellowthroat: Also reported at small willow marsh at northern end of Pacifica State Beach and Lake Mathilde remnant east of Crespi Community Center.
p. 3.7-35
ADD: Western pond turtle (Actinemys marmorata). Ca species of special concern Observed basking at San Pedro Creek – (Margaret Goodale personal observation , spring, 2019) (ALSO reported from Laguna Salada)
p. 3.7-39
>> With the completion of the tunnels, Hickman’s cinquefoil is no longer threatened by the Devil’s Slide Bypass highway project. Update. p. 3.7-53 Impact of the General Plan
ADD: Western Snowy Plover as a special status wildlife species and identify Pacifica State Beach as ESHA.
p. 3.7-56
CO-I-1 Creek Protection and Restoration
• Enforcing restrictions on the planting of invasive species near creek areas; • Requiring minimum setbacks from the top of creek banks for development proposed adjacent to creeks, in keeping with City regulations and Best Management Practices. >> Specify “restrictions” and “minimum seatbacks”
p 3.7-59
CO-I-37 Protection of … During Construction
>> ADD Western Pond Turtles
p. 3.7-6
>> ESTABLISH ROBUST Habitat Conservation Plans and Natural Community Conservation Plan
p. 3.7-61 (Impact of the General Plan)
“…and San Pedro Creek is very close to the San Pedro Site.” >> Clearly Identify and add DETAIL ABOUT THE ”SAN PEDRO SITE” CO-I-28 Protection of Environmentally Sensitive Habitat Area (ESHA). Protect all sensitive species with defined or potential habitat…
CO-I-29 Verification of ESHA
>> Most endangered or threatened species have been listed due to habitat limitations from human encroachment. We CANNOT further limit their habitat.

Remove the possibility of mitigation. Loss of habitat cannot be mitigated. p. 3.7-64
CO-I-46 Shoreline Protection. Continue to prohibit new development requiring shoreline alterations.
>> Specify and clarify date of “existing structures” to be consistent with Coastal Act.

P 3.7-69
CO-I-11 Protect Water Quality through Best Management Practices Stormwater treatment systems must meet the numeric sizing criteria established in the NPDES Permit, and must be operated and maintained in compliance with the NPDES Permit.

From: Maria M. Martínez-Mont [
Sent: Friday, February 11, 2022 12:52 PM
To: Murdock, Christian [[email protected]]; Public Comment [[email protected]]
Subject: « comments on the DEIR and General Plan »
[CAUTION: External Email]
I've lived in Pacifica for the past 20 years and my family has lived here for over 40 years.

Please do NOT ALLOW for the changes proposed on Sharp park. These will create more traffic and if you want affordable housing why not do it in places that are open like Fresno or up north past Eureka???? that part of the valley? Pacifica doesn't have the infrastructure to handle the traffic anymore, we are already on top of each other.

Plus we do not want the pollution and over population. You will kill the heart of Pacifica if you do this. We are a small town not crowded like the Peninsula or South Bay.

Thank you for your consideration.

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From: Lisa Villasenor - Volosing [
Sent: Tuesday, March 8, 2022 8:12 PM
To: Public Comment [[email protected]]; Murdock, Christian [[email protected]]
CC: Richard Harris [
Subject: 2022 Draft General Plan, and EIR Public Comment, SFPGA letter re Sharp Park Golf Course
Attachments: Villasenor Ltr to Pacifica Planning Dept_03082022.pdf [CAUTION: External Email]
Dear Pacifica Planning Department/Mr. Murdock,
See attached my letter in support of Mr. Richard Harris' letter concerning Sharp Park Golf Course as Pacifica Historic Site and Historic Resource
Thank you,
Lisa Villasenor-Volosing
--
Law Offices of Lisa A. Villasenor
Bus/Cell:

Email:

Of Counsel for
The Hassell Law Group
, SF, CA 94132
Ph:

Fax:

Email:

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March 8, 2022
Sent via e-mail: [email protected] and “[email protected]” Pacifica Planning Department
Attn: Christian Murdock, Deputy Director
Pacifica, CA 94044
Re: 2022 Draft General Plan, and Environmental Impact Report Public Comment San Francisco Public Golf Alliance Requests Revisions to the 2022 Draft General Plan and Environmental Impact Report, to Identify Sharp Park Golf Course as Pacifica Historic Site and Historic Resource Dear Pacifica Planning Department,
As a Pacifica resident since 2005 and long time lady golfer and supporter of the Sharp Park Golf Course and its historical clubhouse, I am expressing my support for and agreement with Mr. Richard Harris’ letter dated 3/7/22, regarding Sharp Park Golf Course is a historical site. I have reviewed Mr. Harris’ 3/7/22 letter on behalf of San Francisco Public Golf Alliance, and I agree with its analysis and its call for Sharp Park to be listed and designated a Pacifica historic site and historic resource.

Thank you,
Lisa Villasenor-Volosing
Pacifica, CA 94044
From: Remi Tan [
Sent: Saturday, February 26, 2022 4:39 PM
To: Murdock, Christian [[email protected]]; _City Council Group [[email protected]]; Woodhouse, Kevin [[email protected]]; Wehrmeister, Tina [[email protected]]; Public Comment [[email protected]]; Berman, Lauren [[email protected]]; Hauser, Samantha [[email protected]]; Nibbelin, John [[email protected]]; Leal, David [[email protected]]; Godwin, James [[email protected]]; Domurat, George [[email protected]]; Ferguson, Alex [[email protected]]; O'Connor, Bonny [[email protected]] Subject: 2022-01 Pacifica General Plan - Public Comment Draft - Comments - DEIR Housing [CAUTION: External Email]
Dear City Council and City Planning:

I was looking at the DEIR exec summary and the housing number is still to low at 900... The DEIR needs to be completely updated to reflect the higher RHNA numbers and the increased service retail that the new housing would support. Also the DIER needs to be updated to reflect the increased traffic, pollution, transit, and other environmental impacts would increase and need to be accounted for with the higher RHNA numbers.

Thank you and Best Regards,
Remi Tan, AIA, LEED AP BD+C
Architecture, Green/Sustainability Consulting, and Real Estate Investment Pacifica, CA
Virus-free. www.avast.com
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From: Remi Tan [
Sent: Saturday, January 8, 2022 11:48 AM
To: Murdock, Christian [[email protected]]; O'Connor, Bonny [[email protected]] Subject: 2022-01 Pacifica General Plan - Public Comment Draft - Comments - Housing [CAUTION: External Email]
Chris and Bonnie: I have the following comments on the draft public comment General Plan The planned housing quantity of 990 units by 2035 is inadequate and does not cover the job creation of 1,470 jobs by 2040 and is also short of the 1,892 RHNA required housing units to be built by 2031. (See excerpts from the Jan 2022 Public Comment Draft General Plan and the ABAG RHNA.) Also given that the majority of the jobs projected to be created are in the retail and service sectors (which is in line with the proposed increase in tourism), and these jobs are typically low paying, we need to add much more housing and most of this should be affordable housing.

Given the recent astronomical rise in Pacifica real estate values, Pacifica needs to increase housing quantities beyond the RHNA allocation to stabilize prices by increase supply to meet demand.. The City should work with other Bay Area cities and counties and ABAG to engage a study by an economist that would analyze job creation and population increase in the Bay Area and determine the amount of housing that needs to be built in Pacifica (and the Bay Area) not only to accommodate the new jobs within commutable distance and population growth but to stabilize rising prices by building enough housing so that demand and supply are equalized.

This new housing should be accounted for in the new General Plan and should be located near transit stops and shopping centers to reduce traffic, and not located on hillsides and toes of hills subject to landslide, in erosion vulnerable coastal edges, or in areas prone to flooding or high tide inundation to avoid loss of life and property due to more severe weather and sea level rise caused by global warming. This may require increase in density and height limits near the transit and shopping centers to accommodate the housing.

Given the dire rising cost situation with housing, and with all the effort and public input in the new General Plan and subsequent zoning updates, all housing projects as well as commercial projects should have asof-right zoning that minimizes additional public, planning commission and city council hearings and meetings to expedite the planning process and the city should coordinate with the Coastal Commission to make sure the General Plan and zoning is designed to make CC approval as of right too.

The city should have an expedited permit process in place and coordinate this expedited permit process with the Coastal Commission for housing locations in the Coastal Zone. Housing projects with high affordability should be top priority in permit expediting Please advise on next steps plans to take in incorporating increased housing and the above measures into the new General Plan.

Thank you and Best Regards,
Remi Tan, AIA, LEED AP BD+C
Architecture, Green/Sustainability Consulting, and Real Estate Investment Pacifica, CA 94044
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From: Clif Lawrence [
Sent: Sunday, January 30, 2022 5:23 PM
To: _City Council Group [[email protected]]; Ferguson, Alex [[email protected]]; Leal, David [[email protected]]; Domurat, George [[email protected]]; Godwin, James [[email protected]]; Nibbelin, John [[email protected]]; Berman, Lauren [[email protected]]; Hauser, Samantha [[email protected]]
CC: Clif Lawrence [ Woodhouse, Kevin [[email protected]]; Wehrmeister, Tina [[email protected]]; Murdock, Christian [[email protected]] Subject: A Tale of Two Documents : DGP & DEIR
[CAUTION: External Email]
A Tale of Two Documents
Dear City Council & Planning Commission
It is the public's role to Review and Comment.

A Passing grade for a General Plan and EIR....would
be "consistency"
BUT how do we establish consistency, if we cannot make
correlations?
Because the two documents are vastly different in their organization, correlations are extremely difficult, if not impossible.

This is not the mayor's fault. But she is in maybe the best position to right the ship.

FIRST...WE NEED MORE TIME
The 2015 FEIR references more than 80 days in that review period.
"What's the rush?"
Thank you for your attention.

Clifford Lawrence
West Fairmont
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From: Debra Etienne [
Sent: Monday, February 14, 2022 9:23 AM
To: Bier, Mary [[email protected]]; Bigstyck, Tygarjas [[email protected]]; Vaterlaus, Sue [[email protected]]; O'Neill, Mike [[email protected]]; Beckmeyer, Sue [[email protected]]
CC: Public Comment [[email protected]]; Murdock, Christian [[email protected]]
Subject: Accurate Fire Hazards Absent in DEIR and GP
[CAUTION: External Email]
Dear Council members and Mr. Murdock:

I am concerned about Wildland fires in our town. The EIR does not adequately address this risk.

In Figure 3.11-2 under the Fire Hazards and Public Safety Services Map, only one area is marked as Very High Fire danger and one very tiny spot is marked as a High fire danger area. Come on, folks! We all know Pacifica is covered in groves of Eucalyptus trees and pine trees. How in the world can you honestly say this map represents our town’s risk of Wildland fires? Under the Fire Hazards section, (page 639) the DIER states, “Pacifica has a substantial risk of woodland fires, with many areas of high and very high threat within the Planning Area.” Well, where are they? How can this statement be made without a map showing these areas throughout town? Additionally, this statement is contradicted later as shown below. Why don’t they contain the same information?
Further, under the Wildland Fires section, the document states, “As an urbanized community, wildfire hazard is minimal in most of Pacifica city limits. However, areas along the southwestern perimeter within the Sphere of Influence and in San Pedro Valley County Park are designated as Very High…..” It then follows up with, “ Land adjacent to these areas that is within city limits is low and very low density residential development.” Not true.

These statements do not accurately reflect the amount of potential danger we face with all of our trees. You all live here. Look around your backyards and hills. They are covered in Eucalyptus groves and many areas have Pine trees lining the properties and streets. Have you honestly driven around town and documented all the thick groves of trees surrounding our homes? How can we assess our fire danger when we haven’t accurately documented it? Why aren’t these areas considered in looking at potential fire dangers within our city limits:
• Oddstad Park where Spindrift Theatre is located off Crespi — huge groves • Hill behind Christian school on Seville Dr. — huge groves • Strip of forest behind Park Mall and below Alicante Drive. • Hill above/behind Ortega Elementary and downside of Banyan • Everglades drive going up the hill, huge grove on right, below Water tank accessed from Big Sur Dr.
• On hill above Terra Nova HS, long grove.
• Hill above Cabrillo Elementary and below water tanks off Fassler — lots of trees clustered there
• Corridor between Fassler and Rockaway Beach Ave.
• Hill above Lumber Yard on Hwy One
• South Hill behind Reina Del Mar and between Fassler
• Rifle Range Road has lots of pines lining it and there’s many trees in the Golf Course also
• Hill below Gypsy Hill Road and above Brighton Rd.
• Hill above Good Shepard School
• All the City’s "Green Belt” areas behind homes that contain many trees. (My elderly neighbor said our City sold trees for $.01 to residents to encourage planting in the early days.) Now all those trees are huge.

You get the idea. We are in big trouble if a wildfire breaks out here where the trees are so close to homes, business and schools. I can’t find an accurate map that show all these potential fire dangers, even after contacting Fire Safe San Mateo and writing North County Fire Authority.

Please, think this over and ask yourself if you or your family members are protected by this document. I think not. Please take the time to accurately reflect the Wildland fire hazards in our town before approving this document.

Thank you,
Debra Etienne
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From: Richard Grassetti [
Sent: Tuesday, March 8, 2022 3:51 PM
To: Public Comment [[email protected]]
CC: Cherie Chan [
Subject: Additional Attachment to my comment letter on Pacifica GP EIR Attachments: Attachment C GECo Letter.pdf
[CAUTION: External Email]
Hi- Attached find “Attachment C” to my letter sent earlier today. It was too large a file to be sent with the earlier letter. Please include it with our letter. thanks
Richard
Richard Grassetti
Grassetti Environmental Consulting
www.grassettienvironmental.com
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Attachment C: SEA LEVEL RISE AND FLOODING INFORMATION
Mr. Christian Murdoch Page 28
February 28, 2022
ATTACHMENT 2: CITY OF PACIFICA ZONING MAP, P. 31
Mr. Christian Murdoch Page 29
February 28, 2022
ATTACHMENT 3: PACIFIC INSTITUTE SEA LEVEL RISE MAP
Mr. Christian Murdoch Page 30
February 28, 2022
ATTACHMENT 4: STATE OF CALIFORNIA SEA LEVEL RISE GUIDANCE

DOCUMENT
Catalyzed by direction from Governor Brown in 2016, the update to the State of California Sea-Level Rise Guidance (Guidance) reflects advances in sea-level rise science and addresses the needs of state agencies and local governments as they incorporate sea-level rise into their planning, permitting, and investment decisions.

The updated Guidance provides: 1) a synthesis of the best available science on sealevel rise projections and rates for California; 2) a stepwise approach for state agencies and local governments to evaluate those projections and related hazard information in decision-making; and 3) preferred coastal adaptation approaches.

The update to the Guidance was developed by the California Ocean Protection Council (OPC), in coordination with the California Natural Resources Agency, the Governor’s Office of Planning and Research, and the California Energy Commission. This policy document relies on the scientific findings from a recently released report from the OPC’s Science Advisory Team entitled “Rising Seas in California: An Update on SeaLevel Rise,” which synthesized the current state of sea-level rise science, including advances in modeling and improved understanding of the processes that could drive extreme global sea-level rise as a result of ice loss from the Greenland and Antarctic ice sheets.

To ensure that the Guidance was understandable and useful for local and state decision-making, the update process included extensive public outreach, with interviews, listening sessions and public workshops. Close to 400 coastal stakeholders from city, county, and regional government entities, consulting groups, non-profits, state and federal agencies and tribal representatives provided input that helped shape the framework for the Guidance update and associated web resources (which will be available on the State’s Adaptation Clearinghouse and OPC’s website in early 2018).

Available at: https://www.opc.ca.gov/updating-californias-sea-level-rise-guidance/ Separate Attachment, Attachment 4.

State of
California
Sea-Level
Rise Guidance

2018 UPDATE
Table of Contents

EXECUTIVE SUMMARY 3

INTRODUCTION 7

Purpose and Intended Use 8

Frequency of Future Updates 9

BEST AVAILABLE SCIENCE TO SUPPORT PLANNING FOR

SEA-LEVEL RISE IN CALIFORNIA

11 Rising Seas in California: An Update on Sea-Level Rise Science 11

Global Greenhouse Gas Emissions Scenarios 13

Advances in Sea-Level Rise Modeling 14

SEA-LEVEL RISE PROJECTIONS FOR CALIFORNIA 17

GUIDANCE ON HOW TO SELECT SEA-LEVEL RISE PROJECTIONS 21

RECOMMENDATIONS FOR SEA-LEVEL RISE PLANNING & ADAPTATION 28

SEA-LEVEL RISE PROJECTIONS FOR CALIFORNIA 34

CONCLUSION 37

GLOSSARY 39

APPENDICES

Appendix 1: Guidance Document Development 42

Appendix 2: Map of Tide Gauge Locations 44

Appendix 3: Sea-Level Rise Projections For All 12 Tide Gauges 45

Appendix 4: Risk Decision Framework 81

Appendix 5: Questions From The Policy Advisory Committee 82

Executive Summary

THE CLIMATE ACROSS CALIFORNIA
is changing, and the effects, such as rising average
temperatures, shrinking mountain snowpack, more
intense storms, and higher sea levels are expected to
continue and worsen in the coming decades. Sea-level
rise is caused by the thermal expansion of warming
ocean water and melting of land ice as the Earth
warms. It is one of the most obvious manifestations
of the trend of climate change and is an immediate
and real threat to lives, livelihoods, transportation,
economies, and the environment in California.

In April 2017, catalyzed by direction from Governor
Brown and the need to ensure that best available
science was informing sea-level rise planning
decisions in California, a Working Group of the
California Ocean Protection Council’s Science
Advisory Team (OPC-SAT) released a report, entitled
“Rising Seas in California: An Update on Sea-Level
Rise.” The Rising Seas Report was prepared and
peer-reviewed by some of the nation’s foremost
experts in coastal processes, climate and sea-level
rise science, observational and modeling science,
the science of extremes, and decision-making under
uncertainty. The report synthesized the current
state of sea-level rise science, including advances
in modeling and improved understanding of the
processes that could drive extreme global sea-level
rise as a result of ice loss from the Greenland and
Antarctic ice sheets. The report found that:
• Scientific understanding of sea-level rise is
advancing at a rapid pace.
• The direction of sea-level change is clear; sea
levels are rising.
• The rate of ice loss from the Greenland and
Antarctic ice sheets is increasing, and California
is particularly vulnerable to sea-level rise caused
by ice loss from West Antarctica.
• New scientific evidence has highlighted the
potential for extreme sea-level rise.
• Probabilities of specific sea-level increases can
inform decisions.
• Current policy decisions are shaping our coastal
future.
• Waiting for scientific certainty is neither a safe
nor prudent option.

The increased understanding of sea-level rise
projections and polar ice sheet loss warranted
an update to the State’s sea-level rise guidance
document to ensure decisions were based on the
best available science. Additionally, an increased
policy focus requiring state and local governments
to incorporate climate change into decision making
merited an update to address the needs of both state
and local audiences.

This updated document, the “State of California
Sea-Level Rise Guidance” (Guidance), provides a
bold, science-based methodology for state and
local governments to analyze and assess the risks
associated with sea-level rise, and to incorporate
sea-level rise into their planning, permitting, and
investment decisions. This Guidance provides:

1. A synthesis of the best available science on sealevel rise projections and rates for California;

2. A step-by-step approach for state agencies and
local governments to evaluate those projections
and related hazard information in decision
making; and

3. Preferred coastal adaptation approaches.

EXECUTIVE SUMMARY | 3

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
What Has Changed Since the
2013 Update to the Guidance?
New policy context and expanded audience
State agencies were the target audience for the
earlier versions of this Guidance, which was initially
developed in 2010 and updated in 2013. However,
over the past five years, there has been a multitude
of policy and legislative directives and mandates
focused on improving climate adaptation and
resiliency in California at both the state and local
level, including:
• Governor Brown’s Executive Order B-30-15
directing state agencies to factor climate change
into their planning and investment decisions;
• Senate Bill 379 (Jackson) requiring local
governments to incorporate climate adaptation and
resiliency strategies into their General Plans; and
• Senate Bill 246 (Wieckowski), which established
the Governor’s Office of Planning and Research’s
Integrated Climate Adaptation and Resiliency
Program to coordinate local and state climate
adaptation strategies.

With this increased policy direction and improved
understanding of possible impacts, the 2018
Guidance aims to respond to the needs for guidance
that can help cities, counties and the State prepare
for, and adapt to, sea-level rise.

Significant advances in the scientific
understanding of sea-level rise.
• Scenario-based versus probabilistic sea-level
rise projections. The 2013 version of the State’s
sea-level rise guidance provided scenariobased sea-level rise projections based on a 2012 National Research Council report; these
scenario-based projections were partially but
not fully tied to specific emissions scenarios
presented in the Intergovernmental Panel on
Climate Change’s Fourth Assessment Report and
do not include a likelihood of occurrence. Since
the 2013 Guidance, the scientific community
has made significant progress in producing
probabilistic projections of future sea level rise,
and the team of scientists advising the Ocean
Protection Council (OPC) on this Guidance
strongly recommended that decision-makers
use probabilistic projections to understand
and address potential sea-level rise impacts
and consequences. This updated Guidance
thus incorporates probabilistic sea-level rise
projections, which associate a likelihood of
occurrence (or probability) with sea-level rise
heights and rates, and are directly tied to a range
of emissions scenarios.
• H++ scenario. The probabilistic projections
may underestimate the likelihood of extreme
sea-level rise (resulting from loss of the West
Antarctic ice sheet), particularly under high
emissions scenarios. Therefore, the 2018 update
to the Guidance also includes an extreme
scenario called the H++ scenario. The probability
of this scenario is currently unknown, but its
consideration is important, particularly for highstakes, long-term decisions.

The science on sea-level rise will continue to evolve,
possibly significantly, in coming years. Continual
updates to our scientific understanding must be
expected as observations and models improve, and
as the environment continues to change. Planners
should remain cognizant of this evolving picture,
while at the same time beginning to plan today
under this uncertainty. This Guidance is based on the
recognition that it is no longer appropriate to assume
a static environment in planning and decision making
and that communities can nonetheless effectively
plan and take action in such changing conditions.

Extended stakeholder engagement in
Guidance development.

The 2018 update to the Guidance was developed by
OPC, in close coordination with a Policy Advisory
Committee with representation from the California
Natural Resources Agency, the Governor’s Office
of Planning and Research, and the California
Energy Commission. To improve coordination and
consistency in sea-level rise planning, OPC also
collaborated closely with state coastal management
agencies and other member agencies of the State’s
Coastal and Ocean Working Group of California’s
Climate Action Team (CO-CAT). In addition, OPC,
with assistance from the Ocean Science Trust
EXECUTIVE SUMMARY | 4

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
and engagement experts, solicited input from coastal stakeholders including local governments, regional agencies, federal agencies, coastal consultants, environmental groups, Tribes, and others to better understand the needs and concerns related to planning for sea-level rise and related risks across the state.

Sea-level rise risk analysis and decision framework.

This Guidance provides a step-wise approach to help decision makers assess risk by evaluating a range of sea-level rise projections and the impacts or consequences associated with these projections. Depending on the finite factors of a proposed project’s location and lifespan, decision makers can evaluate the potential impacts and adaptive capacity of the project across a spectrum of sea-level rise projections. This analysis will enable state agencies and local governments to incorporate the latest sea-level rise projections and related hazard information to consider in different types of decisions across California.

The following steps, outlined in the figure and in more detail below, provide a decision framework to evaluate the consequences and risk tolerance of various planning decisions. This framework should be used to guide selection of appropriate sealevel rise projections, and, if necessary, develop adaptation pathways that increase resiliency to sea-level rise and include contingency plans if projections are exceeded or prematurely reached:
>> STEP 1: Identify the nearest tide gauge.
>> STEP 2: Evaluate project lifespan.
>> STEP 3: For the nearest tide gauge and project lifespan, identify range of sea-level rise projections.
>> STEP 4: Evaluate potential impacts and adaptive capacity across a range of sea-level rise projections and emissions scenarios. >> STEP 5: Select sea-level rise projections based on risk tolerance and, if necessary, develop adapation pathways that increase resiliency to sea-level rise and include contingency plans if projections are exceeded.

EXECUTIVE SUMMARY | 5

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
Preferred Coastal Adaptation Planning
Approaches.

This Guidance expands the preferred coastal
adaptation planning approaches identified in OPC’s
previous guidance, incorporating existing law,
expressed policy preferences by the Governor and
Legislature, and the goal of fostering consistency
across coastal and ocean government agencies. The
following is a summary of the new recommendations:
• Adaptation strategies should prioritize
protection of vulnerable communities and
take into consideration social equity and
environmental justice.
• Coastal habitats and public access should be
protected and preserved.
• Adaptation strategies should consider the
unique characteristics, constraints and values of
water-dependent infrastructure, ports and Public
Trust uses.
• Acute increases in sea-level rise caused by
storm surges, El Niño events, king tides, or large
waves should be considered. These events could
produce significantly higher water levels than
sea-level rise alone and will likely be the drivers
of the strongest impacts to coastal communities,
ecosystems, and infrastructure.
• Cross-jurisdictional coordination and consistency
among permitting entities should be sought
in selecting sea-level rise projections. These
entities should also prioritize implementation
of consistent or complementary adaptation
strategies.
• Local conditions, including the diversity
of shoreline types, natural conditions, and
community characteristics, should be evaluated
to inform risk tolerance and adaptation decisions.
• Adaptive capacity should be built into project
design and planning.
• Risk assessment and adaptation planning efforts
should be conducted at community and regional
levels, when possible.

Mapping Tools.

This Guidance also describes and provides links to
a variety of geospatial and visualization tools to
assist decision makers in understanding the impacts
of sea-level rise. The document is accompanied by
a library and database of additional resources –
hosted on the State Adaptation Clearinghouse and
OPC’s website – to help visualize change, access
funding opportunities, gather policy and scientific
background related to specific jurisdictions, and
provide additional support to address a challenge
of this nature and magnitude. This library and
database will be released in mid-2018 when the State
Adaptation Clearinghouse is publicly launched.

How Often Will the State of
California Sea-Level Rise Guidance
be Updated?
Based on recommendations from OPC’s Scientific
Working Group, OPC anticipates updating the
Guidance periodically, and at a minimum of every five
years, to reflect the latest scientific understanding
of climate change sea-level rise in California. Rapid
advances in sea-level rise and climate science, and
subsequent release of relevant, peer-reviewed
studies from the Intergovernmental Panel on
Climate Change (IPCC), state and national climate
assessments, and equivalently recognized sources
may generate the need for more frequent updates.

By incorporating periodic updates at least every five
years, this Guidance attempts to establish a strong
foundation for sea-level rise planning and decision
making at both local, regional, and statewide scales
that can be perpetuated in future updates to sealevel rise projections.

In developing this Guidance, the State took
intentional action to engage users and decision
makers to ensure that the scientific information and
policy direction was understandable and useful for
sea-level rise planning and adaptation efforts. Going
forward, OPC will continue to prioritize opportunities
for co-production of future decision-support
products by scientists, practitioners, and policy and
decision makers to further improve the translation of
sea-level rise science into action.

EXECUTIVE SUMMARY | 6
Introduction
The climate across California is changing,
and the effects, such as rising average
temperatures, shrinking mountain
snowpack, more intense storms, and
higher sea levels are expected to continue
and worsen in the coming decades.

Sea-level rise, caused by the thermal
expansion of warming ocean and melting
of land ice as the Earth warms, is one
of the most obvious manifestations
of the trend of climate change and is
an immediate and real threat to lives,
livelihoods, transportation, economies,
and the environment in California.

The impacts of sea-level rise on California are
significant. The vast majority of California’s
population lives in coastal counties and will directly
experience the effects of sea-level rise on homes,
roads, public services, and infrastructure. More
frequent and chronic flooding and erosion are
inevitable. Inland populations are not immune. For
example, Sacramento-San Joaquin River Delta
communities can expect to see inundation, saltwater
intrusion, and transportation disruptions (for
people and goods); and even further from the San
Francisco Bay and California coast, communities
will experience the far-reaching ripple effects of
coastal changes on lives and livelihoods. California’s
ocean economy – including tourism, recreation
and marine transportation – is the nation’s largest,
valued at over $44 billion per year.1
This important
and lucrative sector will be directly disrupted by the
effects of sea-level rise.Many of the facilities and
much of the infrastructure that support California’s

1. Kildow, Judith, Colgan, Charles, and Johnston, Pat. “Coastal and Ocean Economic Summaries of the Coastal States - Update 2016” National Ocean Economics Program, Center for the Blue Economy, Middlebury Institute of International Studies at Monterey. 2016. http://centerfortheblueeconomy.org/2016-noep-report INTRODUCTION | 7

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
ocean economy, as well as the state’s many miles of
public beaches, lie within a few feet of the present
high-tide line and therefore are at risk from future
sea-level rise and coastal storm events as a result of
a changing climate.

Because the threats cascade beyond the immediate
coastline, a proper and coordinated response and
clear guidance about how to plan and prepare for
change is crucial. California has exhibited strong and
global leadership across both climate adaptation
and mitigation. This Guidance seeks to build upon
that leadership by providing a bold science-based
methodology for state and local governments to
analyze and assess the risks associated with sealevel rise. Catalyzed by direction from Governor Brown in 2016, this Guidance document reflects
advances in sea-level rise science and addresses the
needs of state agencies and local governments as
they incorporate sea-level rise into their planning,
permitting, and investment decisions.

State agencies were the target audience for
the earlier versions of this Guidance, which was
initially developed in 2010 and updated in 2013.

However, over the past five years, there has been
a multitude of policy and legislative directives and
mandates focused on improving climate adaptation
and resiliency in California at both the state and
local level, including: Governor Brown’s Executive
Order B- 30-15 directing state agencies to factor
climate change into their planning and investment
decisions; Senate Bill 379 (Jackson) requiring local
governments to incorporate climate adaptation and
resiliency strategies into their General Plans; and
Senate Bill 246 (Wieckowski), which established
the Governor’s Office of Planning and Research’s
Integrated Climate Adaptation and Resiliency
Program (ICARP) to coordinate local and state
climate adaptation strategies.2 Increased policy
direction and improved understanding of possible
impacts are driving the need for guidance that can
help cities, counties, and the State prepare for, and
adapt to, sea-level rise.

2. Executive Order B-30-15 (2015): https://www.gov.ca.gov/news.php?id=18938; SB 379 (Jackson), Land use: general plan: safety element: https://leginfo.legislature.ca.gov/faces/billTextClient.xhtml?bill_ id=201520160SB379; SB 264 (Wieckowski), Integrated Climate Adaptation and Resiliency Program: https:// leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201520160SB246 In parallel with California’s leadership across the
climate change policy landscape, advances in
scientific understanding warranted an update to the
Guidance to ensure decisions were based on the best
available science.3 These advances include improved
sea-level rise modeling (namely, improved methods
for estimating probabilities of local sea-level change) and better understanding of potential ice loss from
the Greenland and Antarctic ice sheets – and the
implications of this loss for both global average sealevel rise and sea-level rise off the West Coast of the United States.

The 2018 update to the Guidance was developed
by OPC, in coordination with the California Natural
Resources Agency, the Governor’s Office of
Planning and Research, and the California Energy
Commission. To ensure that the updated Guidance
was understandable and useful for local and state
decision making, the update process included
extensive public outreach, with interviews, listening
sessions and public workshops to solicit input from
local, regional, state and federal stakeholders. To
improve coordination and consistency in sea-level
rise planning, OPC also collaborated closely with
state coastal management agencies and other
member agencies of the State’s Coastal and Ocean
Working Group of California’s Climate Action Team
(CO-CAT). See Appendix 1 for a full summary on the
Guidance development.

Purpose and Intended Use
The purpose of this Guidance is to assist decision makers at state and local levels in planning for, and making
decisions about, sea-level rise and related coastal
hazards in light of the current state of the science.

This Guidance aims to:

1. Synthesize – at a high level – the key findings
of the science report solicited in preparation
for this Guidance update, thereby establishing
what constitutes “the best available science,”
and outlining sea level projections and rates for

3. The 2013 document incorporated the sea-level rise projections from the 2012 National Research Council report on sea-level rise along the West Coast titled: “Sea-Level Rise for the Coasts of California, Oregon, and Washington: Past, Present, and Future”: https://www.nap.edu/read/13389/chapter/1 INTRODUCTION | 8

STATE OF C ALIFORNIA SEA-LEVEL RISE GUIDANCE
California, for purposes of planning and decision
making by state and local governments;

2. Provide a step-by-step approach for state
agencies and local governments to incorporate
and adapt to the latest sea-level rise projections
and related hazard information in different types
of decisions across California; and

3. Articulate OPC’s preferred coastal adaptation
planning approaches in the context of existing
law, expressed policy preferences by the
Governor and the Legislature, and OPC’s goal
to foster consistency across coastal and ocean
government agencies.

This Guidance is consistent with OPC’s commitments
to use the best available science in the management of
ocean resources, to employ a precautionary approach
in the face of scientific uncertainty and the potential for significant harm, and to improve coordination
across government agencies in addressing the
complex challenges of climate change.4
This statewide policy document is necessarily a
high-level framework that allows state agencies,
local authorities and other users to incorporate the
essential principles and recommendations while
accommodating the diversity of processes and
decisions across agencies and authorities. It is not
a “how-to” guide but rather a guiding framework.

Thus, accompanying this policy Guidance is a library
and database of resources to help visualize change,
access funding opportunities, gather policy and
scientific background related to specific jurisdictions, and in general provide additional support to address
a challenge of this nature and magnitude. This
database and library of resources will be available
on the State Adaptation Clearinghouse5 in mid-2018,
as well as OPC’s website. It draws on an extensive
resource database developed pursuant to AB 2516,6
as well as additional resources compiled in response
to outreach conducted as part of the Guidance
update process.

Planning, permitting, and investment decisions
initiated after OPC’s adoption of the 2018 Guidance

4. http://www.opc.ca.gov/about/

5. https://www.opr.ca.gov/s_icarpclearinghouse.php

6. https://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201320140AB2516 should incorporate the updated analysis and
adaptation measures described below. Recognizing
the considerable time and resources necessary to
incorporate sea-level rise into planning processes,
planning or development projects currently
underway at the time of Guidance adoption should
complete those efforts while evaluating potential
adaptation pathways to prepare for projected
increases in sea-level rise contained herein. To the
extent possible, and where applicable, projects in the
scoping or early stages at the time of the Guidance
adoption should adjust sea-level rise projections
to incorporate the latest projections in order to
maximize a project’s lifetime and plan for a more
resilient coastline.

Frequency of Future Updates
Based on recommendations from OPC’s Scientific
Working Group, OPC anticipates updating the
Guidance periodically, and at a minimum of every five
years, to reflect the latest scientific understanding
of climate change driven sea-level rise in California.

Rapid advances in science and subsequent
release of relevant, peer-reviewed studies from
the Intergovernmental Panel on Climate Change
(IPCC), state and national climate assessments, and
equivalently recognized sources may generate the
need for more frequent updates. By incorporating
periodic updates at least every five years, this
Guidance attempts to establish a strong foundation
for sea-level rise planning and decision making
at both local, regional, and statewide scales that
can be perpetuated in future updates to sea-level
rise projections. Wherever possible, California is
integrating and aligning updates to the Guidance
with other State-mandated policy and assessment
efforts, such as the Governor’s Office of Planning and
Research’s (OPR) Integrated Climate Adaptation and
Resiliency Program, the recommendations and next
steps of the Safeguarding California Plan, California’s Fourth Climate Change Assessment, the ClimateSafe Infrastructure Working Group, and various guidance documents issued by the California Coastal
Commission and other regulatory agencies.

INTRODUCTION | 9

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
Guidance Implementation
This high-level Guidance was developed to help state and local governments analyze the risks associated with sea-level rise, and develop precautionary adaptation pathways and strategies that ensure community, regional, and statewide resilience in the face of rising seas. The updated projections and recommendations, which fit within a larger body of work assessing sea-level rise vulnerabilities and preparing for future conditions, may be incorporated by state agencies into planning and investment decisions. The Guidance may also be integrated into local government planning and adaptation efforts through statutory, regulatory, and policy mechanisms including, but not limited to: the Coastal Commission’s Local Coastal Programs, the San Francisco Bay Conservation and Development Commission’s permitting process, and General Plans updates that must include climate change adaptation and resiliency strategies pursuant to Senate Bill 379. OPC is committed to continued outreach and collaboration with stakeholders and agencies to ensure effective implementation of this Guidance.

Best Available Science to Support
Planning for Sea-Level Rise in California
Rising Seas In California: An Update
On Sea-Level Rise Science
In April 2017, at the request of OPC, a Working
Group of OPC’s Science Advisory Team (OPC-SAT)
released a report synthesizing the state of sealevel rise science entitled “Rising Seas in California:

An Update on Sea-Level Science” (Rising Seas
Report).7 The Rising Seas Report was prepared and
peer-reviewed by some of the nation’s foremost
experts in coastal processes, climate and sea-level
rise science, observational and modeling science,
the science of extremes, and decision-making
under uncertainty. The Rising Seas Report, which
provides the scientific foundation for this update
to the Guidance, included advances in sea-level
rise modeling and improved understanding of the

7. http://www.opc.ca.gov/webmaster/ftp/pdf/docs/rising-seas-in-california-an-update-on-sea-levelrise-science.pdf processes that could drive extreme global sealevel rise from ice loss from the Greenland and Antarctic ice sheets. This work, along with other
authoritative peer-reviewed science (as long as not
less precautionary than the foundation set forth by
the Rising Seas Report) serve as the best available
science on which to base future planning and
investing decisions in California.

Key findings from Rising Seas in California:

An Update on Sea-Level Rise Science
There are seven key findings from the Rising Seas
Report that provide a succinct summary statement
of the latest understanding of and advancements
in sea-level rise science. The report provides the
foundation for state and local governments to make
decisions associated with sea-level rise utilizing
timely, well-vetted scientific analysis. Its fundamental BEST AVAILABLE SCIENCE TO SUPPORT PLANNING FOR SEA-LEVEL RISE IN CALIFORNIA | 11

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
messages, which are relied on throughout this
Guidance, are as follows:

1. Scientific understanding of sea-level rise
is advancing at a rapid pace.

Projections of future sea-level rise, especially
under high emissions scenarios, have increased
substantially over the last few years, primarily
due to new and improved understanding of
mass loss from continental ice sheets. These
sea-level rise projections will continue to change
as scientific understanding increases and as the
impacts of local, state, national and global policy
choices become manifest. New processes that
allow for rapid incorporation of new scientific
data and results into policy will enable state and
local agencies to proactively prepare.

2. The direction of sea-level change is clear.

Coastal California is already experiencing the
early impacts of a rising sea level, including more
extensive coastal flooding during storms, periodic
tidal flooding, and increased coastal erosion.

3. The rate of ice loss from the Greenland and
Antarctic Ice Sheets is increasing.

These ice sheets will soon become the primary
contributor to global sea-level rise, overtaking
the contributions from ocean thermal expansion
and melting mountain glaciers and ice caps.

Ice loss from Antarctica, and especially from
West Antarctica, causes higher sea-level rise in
California than the global average: for example, if
the loss of West Antarctic ice were to cause global
sea-level to rise by 1 foot, the associated sea-level
rise in California would be about 1.25 feet.

4. New scientific evidence has highlighted the
potential for extreme sea-level rise.

If greenhouse gas emissions continue unabated,
key glaciological processes could cross
thresholds that lead to rapidly accelerating
and effectively irreversible ice loss. Aggressive
reductions in greenhouse gas emissions may
substantially reduce but do not eliminate the
risk to California of extreme sea-level rise from
Antarctic ice loss. Moreover, current observations
of Antarctic melt rates cannot rule out the
potential for extreme sea-level rise in the future,
because the processes that could drive extreme
Antarctic Ice Sheet retreat later in the century
are different from the processes driving loss now.

5. Probabilities of specific sea-level increases
can inform decisions.

A probabilistic approach to sea-level rise
projections, combined with a clear articulation of
the implications of uncertainty and the decision
support needs of affected stakeholders, is the
most appropriate approach for use in a policy
setting. This report employs the framework of
Kopp et al. 2014 to project sea-level rise for
three representative tide gauge locations along
the Pacific coastline: Crescent City in Northern
California, San Francisco in the Bay Area, and La
Jolla in Southern California. These projections
may underestimate the likelihood of extreme
sea-level rise, particularly under high-emissions
scenarios, so this report also includes an extreme
scenario called the H++ scenario. The probability
of this scenario is currently unknown, but its
consideration is important, particularly for highstakes, long-term decisions.

6. Current policy decisions are shaping our
coastal future.

Before 2050, differences in sea-level rise
projections under different emissions scenarios
are minor but they diverge significantly
past mid-century. After 2050, sea-level
rise projections increasingly depend on the
trajectory of greenhouse gas emissions. For
example, under the extreme H++ scenario rapid
ice sheet loss on Antarctica could drive rates of
sea-level rise in California above 50 mm/year (2
inches/year) by the end of the century, leading
to potential sea-level rise exceeding 10 feet.

This rate of sea-level rise would be about 30-40
times faster than the sea-level rise experienced
over the last century.

BEST AVAILABLE SCIENCE TO SUPPORT PLANNING FOR SEA-LEVEL RISE IN CALIFORNIA | 12

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE

7. Waiting for scientific certainty is neither
a safe nor prudent option.

High confidence in projections of sea-level
rise over the next three decades can inform
preparedness efforts, adaptation actions and
hazard mitigation undertaken today, and prevent
much greater losses than will occur if action
is not taken. Consideration of high and even
extreme sea levels in decisions with implications
past 2050 is needed to safeguard the people and
resources of coastal California.

Global Greenhouse
Gas Emissions Scenarios
The pace and severity of sea-level rise will depend
on several factors, including – most importantly –
the pace and scale of global greenhouse gas (GHG)
emissions and the success of subsequent reduction
measures over this century. During the past five years, the atmospheric greenhouse gas concentrations
have continued to increase. Since late 2015,
measurements of the atmospheric CO2 concentration
have consistently exceeded 400 parts per million
(PPM). Recent concentrations are approximately
45% higher than the pre-industrial level, and about

2.5% higher than in 2012. Increases in CO2 and other
greenhouse gases have resulted in the Earth’s climate
system absorbing more energy than it is emitting
back to space. More than 90% of this excess heat
is being captured by the global ocean, leading to a
subsequent increase in sea surface temperatures and
ocean heat content. Rising temperatures are melting
glaciers and ice sheets. Combined with the expansion
of seawater as it warms, these changes are causing
sea levels to rise.

For this Guidance, the emissions scenarios included
are the same as those used by the Intergovernmental
Panel on Climate Change’s Fifth Assessment Report
(IPCC Fifth Assessment) and are called Representative
Concentration Pathways or RCPs. There are four
RCPs, named for the associated radiative forcing level, in watts per square meter, in 2100: RCP 8.5, 6.0, 4.5
and 2.6. Each RCP represents a family of possible
underlying socioeconomic conditions, policy options
and technological considerations, spanning from a
low-end scenario (RCP 2.6) that requires significant
emissions reductions to a high-end, “business-asusual,” fossil-fuel-intensive emission scenario (RCP

8.5). For this Guidance, we focus on RCP 2.6 and RCP

8.5 to bound a range of potential sea level futures
based on GHG emissions trajectories.

RCP 8.5, often referred to as a “business-as-usual”
scenario, is consistent with a future where there
are few global efforts to limit or reduce emissions.

Under RCP 8.5, global CO2 emissions nearly double
between years 2015 and 2050. At the other end of
the spectrum, RCP 2.6 is an aggressive emissions
reduction scenario that assumes global greenhouse
gas emissions will be significantly curtailed. Under
this scenario, global CO2 emissions decline by about
70% between 2015 and 2050, to zero by 2080, and
below zero thereafter. Though more aggressive, RCP

2.6 most closely corresponds to the aspirational
goals of the United Nations Framework Convention
on Climate Change (UNFCCC) 2015 Paris Agreement,
which calls for limiting global mean warming to less
than 2°C and achieving net-zero greenhouse gas
emissions in the second half of this century.

We include RCP 8.5 as an upper bound for California’s
sea-level response projections because thus far, our
greenhouse gas emissions worldwide have continued
to follow the business-as-usual trajectory. Without
a significant and timely commitment to reducing
emissions across the globe, we will remain on this
dangerous trajectory. We include RCP 2.6 as a lower
bound because, although it will be challenging to
achieve, it is important that we align with California’s ambitious greenhouse gas reduction efforts. California
has established emission reduction targets through
efforts such as Assembly Bill 32 (Global Warming
Solutions Act of 2006, which requires California to
reduce its GHG emissions to 1990 levels by 2020),8
Senate Bill 32 (which codifies a 2030 emissions
reduction target of 40% below 1990 levels),9 and the
Under2 Coalition.10 Throughout this Guidance, we refer
to RCP 8.5 and RCP 2.6 as “high-emissions” and “lowemissions” scenarios, respectively.

8. http://www.leginfo.ca.gov/pub/05-06/bill/asm/ab_0001-0050/ab_32_bill_20060927_chaptered.pdf

9. https://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201520160SB32

10. Under2 Coalition: Subnational Global Climate Leadership Memorandum of Understanding:
http://under2mou.org/
BEST AVAILABLE SCIENCE TO SUPPORT PLANNING FOR SEA-LEVEL RISE IN CALIFORNIA | 13

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
Advances in Sea-Level Rise Modeling
The OPC Scientific Working Group extensively
analyzed different scientific approaches to
modeling sea-level rise. They ultimately concluded
that the best available approach today is the
comprehensive probability approach based on
Kopp et al. 2014, described below. Recognizing
that the comprehensive probability approach may
underestimate the likelihood of extreme sea-level
rise, particularly under high emission scenarios,
the Scientific Working Group also concluded
that the H++ extreme sea-level rise scenario in
the Fourth National Climate Assessment should
be considered as well. A brief description of the
scientific approaches is described in part here, and in significant detail in Rising Seas.

One approach, commonly referred to as scenariobased projections, focuses on providing scenarios that span a range of possible futures, without
assessing the relative likelihood or probability
of those scenarios. Another approach, called
probabilistic projections, focuses on estimating the
probability of different levels of future sea-level
change, either by estimating a central projection with
an associated range or by attempting to estimate
a comprehensive probability distribution that also
estimates the likelihood of extreme ‘tail’ outcomes.

Probabilistic projections provide estimates of
probability distributions of possible future sea-level
rise outcomes, whereas scenario-based projections
do not forecast future changes, but describe
plausible conditions that support decision making
under uncertainty.

DISCUSSION OF

PROBABILISTIC PROJECTIONS
Probabilistic projections of sealevel rise included in this Guidance, based on Kopp et al. 2014 and the
Rising Seas Report, represent the
best available science. However,
it is important to understand how
these projections are developed
and recognize that they serve as
a guide for decision makers to
understand current knowledge
rather than as precise predictions of
future conditions. As with all climate
change projections, methodologies
will continue to evolve over time as
scientific knowledge and modeling
capabilities improve.

Bayesian Probabilities:

Scientific statements about
the probability or likelihood of
different future pathways, such
as those made by probabilistic
sea-level rise projections or by
the Intergovernmental Panel on
Climate Change, are examples of
Bayesian probabilities. Bayesian
probabilities are based upon a
synthesis of multiple lines of evidence
and represent an assessment of
the strength of the observational,
modeling, and theoretical evidence
supporting different future outcomes.

Probabilistic projections differ from
frequentist probabilities, as described
below.

Frequentist Probabilities:

Frequentist probabilities are based
on the historical frequency of
occurrence, such as those commonly
seen in estimating disease rates or
determining flood risk. For example,
the 1% annual exceedance probability
flood (or the 100-year flood) is
a flood of a level that historically
occurred in about 1 in 100 years.

A Bayesian probabilistic framework
can support improved decision
making and easily integrate new
lines of scientific evidence but may
under- or overestimate sea-level rise
contributions beyond 2050 and could
lead to confusion if decision makers
are unclear about the difference
between Bayesian and frequentist
probabilities.11 Nonetheless,
probabilistic projections represent
consensus on the best available
science for sea-level rise projections
through 2150. With continued
advances in sea-level rise science,
it is expected that probabilistic
projections will change in the future.

However, the evolving nature of sealevel rise projections does not merit taking a ‘wait and see’ approach.

Acting now is critical to safeguard the
people and resources of California.

11. D. Behar, R.Kopp, R. DeConto, C. Weaver, K. White, K. May, R.

Bindschadler. Planning for Sea Level Rise: An AGU Talk in the Form of a Co-Production Experiment Exploring Recent Science. December 2017. https://www.wucaonline.org/assets/pdf/pubs-aguconsensus-statement.pdf BEST AVAILABLE SCIENCE TO SUPPORT PLANNING FOR SEA-LEVEL RISE IN CALIFORNIA | 14

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
Importantly, the scenario-based and probabilistic
approaches differ in how they represent the
dependence of future sea-level change on specific
greenhouse gas emission scenarios (RCPs).

Scenario-based projections are often informed by
greenhouse gas emissions scenarios but may not be
tied to specific RCPs and do not include a measure
of likelihood of occurrence. In contrast, probabilistic projections estimate probability distributions
regarding sea-level rise under the various RCPs. It is
important to note that probabilistic projections do
not provide actual probabilities of occurrence of sealevel rise but provide probabilities that the ensemble of climate models used to estimate contributions
of sea-level rise (from processes such as thermal
expansion, glacier and ice sheet mass balance,
and oceanographic conditions, among others) will
predict a certain amount of sea-level rise. As climate
science continues to evolve and models are updated
in the future, the probability distribution of model
results - and the associated probabilities - are also
likely to change.

The 2013 OPC Guidance was based on scenariobased sea-level rise projections from the 2012 National Research Council report, which produced
a set of three scenarios (low, central, and high),
with greater weight given to the central scenario.

Subsequently, in 2013, the IPCC Fifth Assessment
Report adopted a probabilistic approach and
produced estimates of the likely range of global sealevel rise under different emission scenarios, where ‘likely’ covers the central 66% of the probability
distribution (i.e., the sea levels that fall within the range created by the value that is 17% likely to occur
and the value that is 83% likely to occur). The IPCC
Fifth Assessment Report did not estimate sea-level
rise outside these central 66% probability ranges or
produce local projections for California.11
The IPCC Fifth Assessment served as a starting point
for further probabilistic modeling and represented
a shift away from scenario-based approaches.

However, the absence of local projections and the
failure to account for estimated probabilities outside
the 66% range led Kopp et al. 2014 to synthesize

12. See Rising Seas Report, page 19
BEST AVAILABLE SCIENCE TO SUPPORT PLANNING FOR SEA-LEVEL RISE IN CALIFORNIA | 15

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
several lines of evidence to estimate comprehensive
probability distributions for global mean sea level
and local relative sea level changes under different
emissions scenarios. In this approach, outputs from
process-based models are combined with estimates
of contributions from the polar ice sheets derived
from an expert elicitation process.13
After considering a range of approaches, the OPC
SAT Scientific Working Group concluded in the Rising
Seas Report that the comprehensive probabilistic
approach employed by Kopp et al. 2014 was most
appropriate for use in a policy setting in California.

Consequently, for projections of sea-level rise other
than that associated with the West Antarctic ice melt
scenario, this Guidance adopts the comprehensive
probabilistic approach. Similar modeling methods
and frameworks have been utilized in other states
and regions, including New York City14, New
Jersey15, Oregon16, regional groups in Washington
State17, and Boston18. It is important to note that
the comprehensive probabilistic approach may
underestimate the likelihood of extreme sea-level
rise in the second half of this century and beyond,
particularly under high-emissions scenarios.19

To address the potential for extreme sea-level rise
as a result of ice loss from the West Antarctic Ice
Sheet, this Guidance adopts the scientific approach
in the Rising Seas Report by incorporating an
extreme scenario—without an assigned probability—
that is based on more recent understanding of
Antarctic marine ice instability. Ice loss from the
West Antarctic Ice Sheet has the potential to be
a key contributor to sea-level rise in California
in the coming decades. The OPC-SAT Scientific
Working Group concluded that the H++ extreme
sea-level rise scenario developed by Sweet et al.
2017 for the Fourth National Climate Assessment
should be considered alongside the Kopp et al.

13. See Rising Seas Report, page 20

14. https://www.nyclimatescience.org/catalog/doc?DocId=vitroIndividual:http://www.nyclimatescience. org/individual/n8040

15. http://njadapt.rutgers.edu/docman-lister/conference-materials/167-njcaa-stap-final-october-2016/file

16. http://www.occri.net/media/1042/ocar3_final_125_web.pdf

17. http://docs.wixstatic.com/ugd/a3bdcc_1c4b6b33caf54836a2cac641b7ebe53b.pdf

18. https://www.boston.gov/sites/default/files/03_climate_ready_boston_digital_ climateprojectionconsensus.pdf

19. See Rising Seas Report, page 22
2014 comprehensive probability distributions for
the RCPs. Sweet et al. 2017 maintained a scenariobased approach, but drew upon the Kopp et al. 2014 framework to localize projections and to discuss the
likelihood of scenarios under different emissions
pathways. Sweet et al. 2017 also developed an
“extreme” scenario, leading to 8.2 feet of global mean
sea-level rise in 2100 that is based on considerations
derived from recent ice-sheet observations and new
model simulations from Deconto and Pollard 201620
and also other attempts in the literature to estimate
‘maximum physically plausible’ sea-level rise.

Including consideration of this rapidly developing
science is critical given the important role of the
Antarctic Ice Sheet in both local and global sealevel rise projections. However, at this point, it is difficult to estimate the probability that the H++
scenario will occur, and when the world may shift
to the H++ trajectory. Although sea-level rise is not
following the H++ scenario at this moment, this
scenario cannot be excluded for the second half
of this century given the potential for non-linear
acceleration of sea-level rise driven by positive
feedbacks of ice-sheet dynamics and the significant
consequences to California’s coastline.

The approach to sea-level rise projections for the
Guidance update is slightly more conservative than
California’s Fourth Climate Assessment, which
is currently underway and due out in fall 2018.

California’s Fourth Climate Assessment directly
adopted the Antarctic projections of Deconto
and Pollard 2016, replacing in full the Antarctic
projections of Kopp et al., 2014. For the purposes
of use in policy guidance, the authors of the Rising
Seas Report chose to include the H++ projections
as a stand-alone scenario rather than incorporating
ice sheet dynamics associated with this extreme into
the model ensemble used to generate probabilistic
projections. Because of the high level of uncertainty
associated with physical processes that would trigger
the H++ scenario and the emerging nature of the
science, the authors felt the stand-alone scenario
application was more appropriate for planning and
permitting decisions at this time.

20. http://www.nature.com/nature/journal/v531/n7596/full/nature17145.html?foxtrotcallback=true BEST AVAILABLE SCIENCE TO SUPPORT PLANNING FOR SEA-LEVEL RISE IN CALIFORNIA | 16

Sea-Level Rise Projections for California

THE RISING SEAS REPORT PRESENTED
a range of sea-level rise projections for a subset
of the active tide gauges in California based on
emission trajectories, acknowledging that projected
sea-level rise has a significant range of variation
as a result of uncertainty in future greenhouse gas
emissions and their geophysical effects, such as
the rate of land ice melt. Below are tables that build
on those included in the Rising Seas Report for
projections over different time frames and emission
scenarios at the San Francisco tide gauge. The same
details included for the San Francisco tide gauge
below can also be found for all 12 active tide gauges
along the California coast21 in Appendix 3.

The baseline for the sea-level rise projections
presented in the Rising Seas Report and this
Guidance is the year 200022. Projections begin at
2030, consistent with the 2013 Guidance; however,
the maximum planning horizon has been extended
to 2150 to support precautionary planning and
decision making for projects with longer lifespans.

21. Active tide gauges locations include: Crescent City, North Spit (Eureka), Arena Cove, Point Reyes, San Francisco, Monterey, Port San Luis, Santa Barbara, Santa Monica, Los Angeles, San Diego and La Jolla; see Appendix 2 for map.

22. The year 2000 baseline is based on the average relative sea-level rise from 1991-2009.

How much sea-level rise will
California experience over
this century?
The following table provides probabilistic
projections for the height of sea-level rise over
various timescales for RCP 2.6 (low emissions) and
RCP 8.5 (high emissions), along with the extreme
H++ scenario (which is a single scenario and not
a probabilistic projection). These numbers do not
include impacts of El Niño, storms or other acute
additions to sea-level rise. As discussed in more
detail below, before 2050, differences in sealevel rise projections under different emissions scenarios are minor, and currently the world is
on the RCP 8.5 emission trajectory. However,
beyond 2050, different emissions pathways will
result in significantly different levels of sea-level
rise. Therefore, this Guidance includes projections
only for a high greenhouse gas emissions scenario
through 2050, and includes projections for both
high and low emissions scenarios from 2050
through 2150.

SEA-LEVEL RISE PROJECTIONS FOR CALIFORNIA | 17

TABLE 1: Projected Sea-Level Rise (in feet) for San Francisco Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

Probabilistic Projections (in feet) (based on Kopp et al. 2014) MEDIAN LIKELY RANGE 1-IN-20 CHANCE 1-IN-200 CHANCE
50% probability
sea-level rise meets
or exceeds…
66% probability
sea-level rise
is between…
5% probability
sea-level rise meets
or exceeds…

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.4 0.3 - 0.5 0.6 0.8 1.0
2040 0.6 0.5 - 0.8 1.0 1.3 1.8
2050 0.9 0.6 - 1.1 1.4 1.9 2.7
Low emissions 2060 1.0 0.6 - 1.3 1.6 2.4
High emissions 2060 1.1 0.8 - 1.5 1.8 2.6 3.9
Low emissions 2070 1.1 0.8 - 1.5 1.9 3.1
High emissions 2070 1.4 1.0 - 1.9 2.4 3.5 5.2
Low emissions 2080 1.3 0.9 - 1.8 2.3 3.9
High emissions 2080 1.7 1.2 - 2.4 3.0 4.5 6.6
Low emissions 2090 1.4 1.0 - 2.1 2.8 4.7
High emissions 2090 2.1 1.4 - 2.9 3.6 5.6 8.3
Low emissions 2100 1.6 1.0 - 2.4 3.2 5.7
High emissions 2100 2.5 1.6 - 3.4 4.4 6.9 10.2
Low emissions 2110* 1.7 1.2 - 2.5 3.4 6.3
High emissions 2110* 2.6 1.9 - 3.5 4.5 7.3 11.9
Low emissions 2120 1.9 1.2 - 2.8 3.9 7.4
High emissions 2120 3 2.2 - 4.1 5.2 8.6 14.2
Low emissions 2130 2.1 1.3 - 3.1 4.4 8.5
High emissions 2130 3.3 2.4 - 4.6 6.0 10.0 16.6
Low emissions 2140 2.2 1.3 - 3.4 4.9 9.7
High emissions 2140 3.7 2.6 - 5.2 6.8 11.4 19.1
Low emissions 2150 2.4 1.3 - 3.8 5.5 11.0
High emissions 2150 4.1 2.8 - 5.8 5.7 13.0 21.9

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
*Most of the available climate model experiments do not extend beyond 2100. The resulting reduction in model availability causes a small dip in projections between 2100 and 2110, as well as a shift in uncertainty estimates (see Kopp et al. 2014). Use of 2110 projections should be done with caution and with acknowledgement of increased uncertainty around these projections.

SEA-LEVEL RISE PROJECTIONS FOR CALIFORNIA | 18

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
When is sea-level rise going to exceed a particular
height in California?
In addition to understanding the potential range of sea-level rise projections as presented in the table above, it may be helpful for decision makers to understand when a particular level is projected to occur. The following table provides information on the likelihood that sea-level rise will meet or exceed a specific height over various timescales. However, the H++ scenario is not included in this table.

Again, this information is presented for a high-emissions scenario through 2050 and both low- and high-emissions scenarios post-2050. It is important to note that episodic events, such as king tides, storms, El Niños, and waves may cause acute increases in sea level heights sooner than is shown in Table 2 below.

TABLE 2: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in San Francisco
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

SAN FRANCISCO - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030 0.1%
2040 3.3%
2050 31% 0.4%
2060 65% 3% 0.2% 0.1%
2070 84% 13% 1.2% 0.2% 0.1%
2080 93% 34% 5% 0.9% 0.3% 0.1% 0.1%
2090 96% 55% 14% 3% 0.9% 0.3% 0.2% 0.1% 0.1%
2100 96% 70% 28% 8% 3% 1% 0.5% 0.3% 0.2% 0.1%
2150 100% 96% 79% 52% 28% 15% 8% 4% 3% 2%
SAN FRANCISCO - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 43% 1.4% 0.2%
2070 62% 4% 0.6% 0.2% 0%
2080 74% 11% 2% 0.4% 0.2% 0.1%
2090 80% 20% 3% 1.0% 0.4% 0.2% 0.1% 0.1%
2100 84% 31% 7% 2% 0.8% 0.4% 0.2% 0.1% 0.1%
2150 93% 62% 31% 14% 7% 4% 2% 2% 1% 1%
SEA-LEVEL RISE PROJECTIONS FOR CALIFORNIA | 19

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
What will the rate of sea-level rise be in California?
The rate at which sea levels will rise can help inform the planning and implementation timelines of state and local adaptation efforts. Rates of sea-level rise are also important to consider when evaluating the ability of natural and restored coastal habitats to adapt to rising seas. In some cases, sea-level rise may exceed the rate at which habitats, such as coastal wetlands, can accrete sediment, migrate inland or to adjacent neighboring low-lying areas, resulting in flooding and loss and destruction of these important ecological systems. Understanding the speed at which sea level is rising can provide context for planning decisions and establish thresholds for action to better protect habitats and their ecological and resiliency benefits. The information in the table listed below is presented for a high-emissions scenario through 2050 and both low- and high-emissions scenarios post-2050.

TABLE 3: Projected Average Rate of Sea-Level Rise (mm/year) for San Francisco
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column). Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

Probabilistic Projections (mm/yr) (based on Kopp et al. 2014) MEDIAN LIKELY RANGE 1-IN-20 CHANCE 1-IN-200 CHANCE
50% probability
sea-level rise meets
or exceeds…
66% probability
sea-level rise
is between…
5% probability
sea-level rise meets
or exceeds…

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030-2050 6.7 4.5 - 9.3 12 17 26
Low emissions 2060-2080 5.3 3.1 - 8.2 12 22
High emissions 2060-2080 9.5 6.4 - 13 17 28 42
Low emissions 2080-2100 5.2 2.3 - 9.1 14 28
High emissions 2080-2100 11 6.0 - 16 22 37 55
SEA-LEVEL RISE PROJECTIONS FOR CALIFORNIA | 20

Guidance on How to Select Sea-Level Rise Projections

SELECT SEA-LEVEL RISE PROJECTIONS

BY TAKING A STEP-WISE APPROACH

AND CONSIDERING A SUITE OF
FACTORS AND CONDITIONS.

This Guidance summarizes the best available sealevel rise science, which includes probabilistic projections, an extreme scenario, and a recognition
that these projections may change in the future.

Although sea-level projections may change in the
future, when used as part of the risk management
process outlined in this Guidance, they provide
vital information for adaptation actions and hazard
mitigation undertaken today. Decisions about
which sea-level rise projections to select - and the
necessary adaptation pathways and contingency
plans to ensure resilience - will be based on factors
including location, lifespan of the given project or
asset, sea-level rise exposure and associated impacts,
adaptive capacity, and risk tolerance/aversion.

An adaptation pathway is a planning approach
addressing the uncertainty and challenges of climate
change decision-making. It enables consideration of
multiple possible futures, and allows analysis of the
robustness and flexibility of various options across
those multiple futures.23
Adaptive capacity is the ability of a system or
community to evolve in response to, or cope with
the impacts of sea-level rise.24 Assets or natural
resources with high adaptive capacity will likely have
greater flexibility and potential to withstand rising
sea levels. Adaptive capacity may be inherent to the
asset, or can be improved through forward-looking
planning or design (for example, including sufficient
physical space to allow for buffering effects or inland

23. South West Climate Change Portal: Catchment Planning - Using Adaptation Pathway:
http://www.swclimatechange.com.au/cb_pages/adaptation_pathways.php

24. Willows RI, RK Connell (eds.). 2003. Climate Adaptation: Risk, Uncertainty and Decisionmaking. UKCIP Technical Report. Oxford: UKCIP. 154 pp. http://www.ukcip.org.uk/wordpress/wp-content/PDFs/UKCIP-Riskframework.pdf GUIDANCE ON HOW TO SELECT SEA-LEVEL RISE PROJECTIONS | 21

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
migration of habitats, or designing a structure that
can be easily relocated). Adaptive capacity is also
a function of the innate characteristics of a system;
e.g., a community that is chronically under-resourced
may develop effective adaptation strategies but
will likely still be at a disadvantage compared to
communities with more resources for advanced
planning and implementation.

Risk tolerance is the level of comfort associated with
the consequences of sea-level rise and associated
hazards in project planning and design.25 Risk
aversion is the strong inclination to avoid taking
risks in the face of uncertainty. State and local
governments should consider the risks associated
with various sea-level rise projections and determine
their tolerance for, or aversion to, those risks
Assessing risk requires evaluation of two dimensions:
1) uncertainty, which can be analyzed and assessed
using a range of sea-level rise projections, and
2) impacts or consequences, which may require
a combination of quantitative and qualitative
assessments. The step-wise approach we provide
guides decision makers through both dimensions
of the risk analysis. Depending on the finite factors
of location and project lifespan, decision makers
will evaluate the potential impacts and adaptive
capacity of the project across a spectrum of sealevel rise projections. This analysis will enable the decision maker to select the appropriate projection
for the particular project while building in adaptation pathways and contingency plans should that
projection be exceeded. These steps complement
other State guidance documents that provide a step
wise approach to the analysis needed to incorporate
sea-level rise into planning and decision making, such
as the California Coastal Commission’s Sea Level Rise
Policy Guidance26 and Draft Residential Adaptation
Policy Guidance.27

25. Parris A, P Bromirski, V Burkett, D Cayan, M Culver, J Hall, R Horton, K Knuuti, R Moss, J Obeysekera, A Sallenger, J Weiss. 2012. Global Sea-level rise Scenarios for the US National Climate Assessment. NOAA Tech Memo OAR CPO-1. 37 pp. http://scenarios.globalchange.gov/sites/default/files/NOAA_SLR_r3_0.pdf

26. https://documents.coastal.ca.gov/assets/slr/guidance/August2015/0_Full_Adopted_Sea_Level_Rise_ Policy_Guidance.pdf

27. https://documents.coastal.ca.gov/reports/2017/8/w6h/w6h-8-2017-exhibits.pdf#page=2 GUIDANCE ON HOW TO SELECT SEA-LEVEL RISE PROJECTIONS | 22

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
The following steps, outlined in the figure and in more detail below, provide a decision framework to evaluate the consequences and risk tolerance of various planning decisions, and should be used to guide selection of appropriate sea-level rise projections, and, if necessary, develop adaptation pathways that increase resiliency to sea-level rise and include contingency plans if projections are exceeded:
>> STEP 1: Identify the nearest tide gauge.
>> STEP 2: Evaluate project lifespan.
>> STEP 3: For the nearest tide gauge and project lifespan, identify range of sea-level rise projections.
>> STEP 4: Evaluate potential impacts and adaptive capacity across a range of sea-level rise projections and emissions scenarios. >> STEP 5: Select sea-level rise projections based on risk tolerance and, if necessary, develop adapation pathways that increase resiliency to sea-level rise and include contingency plans if projections are exceeded.

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
>> STEP 1: Identify the nearest tide gauge.

Sea levels and rates of sea-level rise will vary
along the California coast due to variable land
elevations resulting from factors such as tectonic
activity and subsidence. This difference between
the height of the sea surface and the height of the
land is called relative sea level, and the National
Oceanic and Atmospheric Administration (NOAA)
provides a summary of the trends in the measured
relative sea level at 12 active tide gauges (water
level recorders) in California that have been
operating for at least 39 years and up to 162
years.28,29 For localized sea-level rise projections,
relative trends in sea level from changes in land
elevation should be factored into the analysis.

Therefore, of the 12 tide gauges across California,
start by identifying the tide gauge nearest to the
project location, in Appendix 2. This step will orient
the user to the appropriate projection table. If
the project is located in an area between two tide
gauges, refer to Appendix 2 to determine which
tide gauge is closest to your location. If the project
is nearly equidistant between two tide gauges, it
is appropriate to interpolate between or average
the two tide gauges. The 12 active tide gauges
along the California coast cannot account for
specific local variation across the entire shoreline
of the state; however, data driven projections using
information from these tide gauges provides the
most scientifically rigorous approach to estimating
localized sea-level rise projections. If additional
scientific data is available, it may be evaluated and
considered in local planning decisions.

28. https://tidesandcurrents.noaa.gov/water_level_info.html

29. See Rising Seas Report, Box 2, page 23
>> STEP 2: Evaluate project lifespan.

Prior to 2050, differences in sea-level rise
projections under different emissions scenarios
are minor. This is because near-term sea-level
rise has been locked in by past greenhouse gas
emissions and the slow response times of the ocean
and land ice to warming. The long-lived nature of
most greenhouse gases means that their impacts
on the environment are felt and experienced long
after being emitted. Comparatively, after 2050,
sea-level rise projections increasingly depend on
the pathway of future greenhouse gas emissions.

Therefore, this Guidance only includes sea-level rise
projections based on a high scenario of greenhouse
gas emissions (RCP 8.5; “high emissions”) through
2050, and includes projections for both the RCP

2.6 “low-emissions” scenario as well as the RCP

8.5, “high-emissions” scenario after 2050 through
2150. The Guidance also includes an extreme sealevel rise scenario, the H++ scenario, which is not tied to a specific emissions trajectory but should
be considered for projects with a lifespan beyond
2050 that have a low tolerance for risk, such as
large power plants, major airports and roads,
wastewater treatment plants, and hazardous waste
and toxic storage sites. The H++ scenario may also
be relevant to communities considering regional
or general plans, climate action plans, local hazard
mitigation plans, regional transportation plans,
and other planning efforts, due to the interrelated
nature of critical infrastructure, homes, businesses,
etc. Determining project lifespan will guide whether
to evaluate sea-level rise projections for the highemissions scenario only (in the case of projects with a lifespan that ends before 2050) or across
the range of high- and low-emissions scenarios for
projects with a lifespan beyond 2050.

GUIDANCE ON HOW TO SELECT SEA-LEVEL RISE PROJECTIONS | 24

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE

JUSTIFICATION FOR RECOMMENDED

LOW, MEDIUM-HIGH AND EXTREME

RISK AVERSION PROJECTIONS
This guidance document will inform a breadth of
planning and adaptation decisions at both the
state and local level. As such, it provides highlevel guidance on the appropriate range of sealevel rise projections to be considered in project planning and design, while providing enough
flexibility to allow for local priorities and tradeoffs to determine final decisions. To ensure that consideration of sea-level rise is precautionary
enough to safeguard the people and resources
of California and that sufficient adaptation
pathways and contingency plans are developed,
we recommend that decisions evaluate a range
of projections based on low, medium-high and
extreme levels of risk aversion:

Projection for decisions with low risk aversion:

Use the upper value of the “likely range” for the
appropriate timeframe. This recommendation
is fairly risk tolerant, as it represents an
approximately 17% chance of being overtopped,
and as such, provides an appropriate projection
for adaptive, lower consequence decisions (e.g.
unpaved coastal trail) but will not adequately
address high impact, low probability events.

Additionally, it is important to note that the
probabilistic projections may underestimate the
likelihood of extreme sea-level rise, particularly
under high-emissions scenarios.

Projection for decisions with medium – high
risk aversion: Use the 1-in-200 chance for the
appropriate timeframe. The likelihood that sealevel rise will meet or exceed this value is low, providing a precautionary projection that can be
used for less adaptive, more vulnerable projects
or populations that will experience medium to
high consequences as a result of underestimating
sea-level rise (e.g. coastal housing development).

Again, this value may underestimate the potential
for extreme sea-level rise.

Projection for decisions with extreme
risk aversion: Use the H++ scenario for the
appropriate timeframe. For high consequence
projects with a design life beyond 2050 that
have little to no adaptive capacity, would be
irreversibly destroyed or significantly costly
to relocate/repair, or would have considerable
public health, public safety, or environmental
impacts should this level of sea-level rise occur,
the H++ extreme scenario should be included in
planning and adaptation strategies (e.g. coastal
power plant). Although estimating the likelihood
of the H++ scenario is not possible at this time
(due to advancing science and the uncertainty
of future emissions trajectory), the extreme sealevel rise projection is physically plausible and will provide an understanding of the implications
of a worst-case scenario.
>> STEP 3: For the nearest tide gauge and project
lifespan, identify range of sea -level rise projections.

Considering a range of different sea-level rise projections allows decision makers to evaluate the vulnerability of people, natural resources and infrastructure under various future flooding conditions, as well as their level of comfort with overor underestimating sea-level rise. Because future projections of sea-level rise along California’s coastline are uncertain (due to uncertainty associated with modeling and the trajectory of global emissions), it is critical to consider a range of projections to understand the consequences of various decisions, determine the tolerance for risk associated with those decisions, and to inform adaptation strategies necessary to prepare for change in the face of uncertainty. We recommend using a set of projections appropriate for low, medium-high and extreme levels of risk aversion to evaluate a spectrum of potential impacts, consequences and responses. (See adjacent call-out box for justification on the recommended projections.)
For the low risk aversion sea-level rise projection, use the upper end in the “likely range” as shown in Table 1 above or in Appendix 3.

For the medium-high risk aversion sea-level rise projection, use the 1-in-200 chance projection. For highly vulnerable or critical assets that have a lifespan beyond 2050 and would result in significant consequences if damaged, the H++ scenario (extreme risk aversion projection) should also be included in planning analyses. For example, for a project in San Francisco with a lifespan to 2050 under a high-emissions scenario (RCP 8.5), the recommended range of projections from Table 1 are:

Low risk aversion projection: 1.1 feet
Medium-high risk aversion projection: 1.9 feet
Extreme risk aversion projection: 2.7 feet
For projects with a lifespan beyond 2050, the range of low, medium-high and extreme risk aversion projections should be evaluated across the range of high and low emissions scenarios (RCP 8.5 and RCP 2.6, respectively). For example, for a project with a lifespan to 2100, the recommended range of projections from Table 1 are:

Low risk aversion projection: 2.4 - 3.4 feet
Medium-high risk aversion projection: 5.7- 6.9 feet
Extreme risk aversion projection: 10.2 feet
GUIDANCE ON HOW TO SELECT SEA-LEVEL RISE PROJECTIONS | 25

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
>> STEP 4: Evaluate potential impacts and adaptive capacity across a range of sea -level rise projections and emissions scenarios.

After the appropriate low, medium-high, and extreme risk aversion projections have been identified based on location and timespan, the next step is to conduct a vulnerability assessment to evaluate the potential impacts of sea-level rise on the project and the project’s adaptive capacity. This can be done using the sealevel rise mapping tools discussed later in this Guidance. In analyzing impacts and adaptive capacity, consider the following questions for each identified sea-level rise projection, which mirror components outlined in OPR’s risk management approach of the Governor’s Office of Planning and Research’s “Planning and Investing for a Resilient California: A Guidebook for State Agencies30”:

Consequence of potential impacts: If sea-level rise is not addressed adequately, will the consequences of the project on equity, environment, economy and governance (both to the development itself and to the surrounding environment and community) be minimal, moderate, or catastrophic?
What is at stake: Will vulnerable communities, coastal habitats, or critical infrastructure be significantly impacted?
Adaptive capacity: Can people, natural systems, and infrastructure readily respond or adapt to rising sea levels?
Economic impacts: Will failure to adequately plan for sea-level rise create significant economic burden now or in the future?
Evaluating these factors will help decision makers understand the vulnerabilities of people, assets and the natural environment under a range of sea-level rise possibilities and determine their tolerance for the risks associated with the consequences of over- or underestimating sea-level rise. This approach aligns with ongoing efforts throughout the state to complete vulnerability assessments, including the California Coastal Commission’s Statewide Sea Level Rise Vulnerability Synthesis.31 OPC recognizes that that the social, economic and environmental impacts of sea-level rise at different levels of exposure may be difficult to quantify and qualify, and ultimate decisions will require a balance of tradeoffs and priorities that may not be consistent across communities or jurisdictions.

30. https://opr.ca.gov/planning/icarp/resilient-ca.html

31. https://documents.coastal.ca.gov/assets/climate/slr/vulnerability/FINAL_Statewide_Report.pdf GUIDANCE ON HOW TO SELECT SEA-LEVEL RISE PROJECTIONS | 26 >> STEP 1: Identity the nearest tide gauge.
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-

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
>> STEP 5: Select sea-level rise projections
based on risk tolerance and, if necessary,
develop adapation pathways that increase
resiliency to sea-level rise and include
contingency plans if projections are exceeded.

OPC recommends utilizing a decision framework
to assist in evaluating tradeoffs and determining
the appropriate sea-level rise projections for the
condition and characteristics of the shoreline
being evaluated. The decision framework in
Appendix 4 builds on the work of OPR in response
to Governor Brown’s Executive Order B-30-15,
as well as the U.S. Climate Resilience Toolkit’s
guidance.32 In general, decision makers may have
a higher tolerance for risk (or lower risk aversion)
when considering projects with a shorter lifespan,
minimal consequences, flexibility to adapt, or low
economic burden as a result of sea-level rise. In this
decision context, it may be appropriate to select
low sea-level rise projections across the range
of RCP 2.6 and 8.5. However, for longer lasting
projects with less adaptive capacity and medium
to high consequences should sea-level rise be
underestimated, we suggest that decision makers
take the more precautionary, more risk-averse
approach of using the medium-high sea-level rise
projections across the range of emissions scenarios.

We further recommend incorporating the H++
scenario in planning and adaptation strategies
for projects that could result in threats to public
health and safety, natural resources and critical
infrastructure, should extreme sea-level rise occur.

In addition to selecting sea-level rise projections,
coastal communities should consider phasing in
short and long-term adaptation strategies over time
when planning for sea-level rise. This concept of
adaptation pathways considers the challenges of
planning for uncertain timing and extent of rising
sea levels while providing a structure for sequencing
adaptation measures using the time horizon of
projected hazards from a changing climate. The
adaptation pathway approach links the choice of

32. https://toolkit.climate.gov/topics/coastal/sea-level-rise near-term adaptation actions with identification of
pre-determined threshold events. Observation of
such threshold events would trigger subsequent
actions in the planning or implementation stages of
adaptation strategies. Often an adaptation pathway
includes low-regret, near-term actions that preserve
future options to adjust if necessary. Observable
events that might trigger new phases of adaptation
might include the extent of flooding, frequency of
damage, or the extent of economic development
along the coast. These triggers should reflect a
community’s risk tolerance, local conditions, and
adaptation vision.

Communities should look for signs that some
adaptation options have run their course and
plan adaptation pathways to transition actions as
needed. Analyzing a worst-case “high” projection
for the planning horizon of the project provides a
conservative upper bound for planning pathways
based on current information. Following this
approach, which is used in other recent sea-level
rise guidance documents33,34 and cited in more
recent policy writing,35,36 a community or project
might consider an adaptive plan, which includes
contingency responses if climate hazards occurs
more quickly than expected. The adaptive plan need
not choose between future options now, but would
include steps to keep future options open. For
instance, the plan could include identifying a future
inland site and zoning the land so that it would
be available in the future if needed. This triggerbased adaptation planning is discussed further in Recommendation 7 below.

33. Coastal Hazards and Climate Change. Guidance for Local Government. New Zealand Government, Ministry for the Environment. http://www.mfe.govt.nz/publications/climate-change/coastal-hazards-andclimate-change-guidance-local-government

34. California Coastal Commission Draft Residential Adaptation Policy Guidance. July 2017. https:// documents.coastal.ca.gov/reports/2017/8/w6h/w6h-8-2017-exhibits.pdf#page=2

35. Haasnoot, M., J. Kwakkel, W. Walker, J. Maat. Dynamic adaptive policy pathways: A method for crafting robust decisions for a deeply uncertain world. Global Environmental Change. 2013. 485-498. https://documents.coastal.ca.gov/assets/slr/guidance/August2015/0_Full_Adopted_Sea_Level_Rise_ Policy_Guidance.pdf

36. Center for Ocean Solutions. Coastal Adaptation Policy Brief. December 2017. http:// centerforoceansolutions.org/sites/default/files/Triggers%20WEB.pdf GUIDANCE ON HOW TO SELECT SEA-LEVEL RISE PROJECTIONS | 27 Recommendations for Sea-Level Rise
Planning and Adaptation
The step-wise approach above
provides guidance on how to select
sea-level rise projections by evaluating
risk and vulnerability. The following
recommendations provide guidance
on preferred sea-level rise planning
and adaptation approaches, with an
understanding that the diversity of
communities, uses, and natural resources
along California’s coastline, as well as
planning for new development versus
existing structures, may merit different
approaches to building resilience.

1. Adaptation planning and strategies should
prioritize social equity, environmental justice and
the needs of vulnerable communities.

Communities of color, low-income communities,
and Native Nations have been, and will continue
to be, disproportionately overburdened by
pollution and climate change. Sea-level rise will
add to those burdens. Impacts such as increased
flooding, damage to homes and roads, disruption
to public transportation, elevated exposure to toxic
materials, and destruction of coastal sacred places
and cultural sites will unduly affect vulnerable
communities. These impacts can manifest as
complete community displacement, loss of places
of ancient and contemporary cultural and historic
significance, loss of personal property, worsened
health, reduced or lost wages, and loss of free or
affordable public access to the coast. Vulnerable
communities may lack financial or other resources
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STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
to plan for sea-level rise as well as the ability to
adequately respond to impacts once they occur.

Sea-level rise planning that prioritizes social equity, environmental justice and protection of the lives
and property of vulnerable communities should
include early public engagement of those who will
be directly or indirectly affected by rising sea levels, a focused characterization of impacts on exposed
populations and communities dependent on critical
assets threatened by sea-level rise, and identification of specific adaptation strategies to minimize or
mitigate these impacts. Engaging communities
that face existing inequalities already (or will face
unequal distribution of sea-level rise impacts) early
in the planning process will ensure that vulnerability
assessments and adaptation strategies accurately
reflect their risk, needs and priorities. State and
local governments should also prioritize technical
support and funding opportunities for planning
and adaptation efforts of vulnerable and Native
communities. Incorporating social equity and
environmental justice in sea-level rise planning and
adaptation strategies should:
• Address environmental contamination risks
for coastal communities adjacent to industry
or toxic sites. Coastal environmental justice
communities tend to have fewer beachfront
homes at risk of inundation, but are often
separated from the coast by strips of industrial
facilities, ports and military installations.

Sea-level rise threatens job sites for local
residents, risks spreading contamination
from cleanup sites, and can damage critical
energy, transportation or other infrastructure.

Prioritizing cleanup of sites threatened by sealevel rise can prevent toxic contamination from spreading into nearby communities.
• Preserve access to and along the beach.

Protecting natural coastlines preserves
affordable outdoor recreation access for
communities that often lack parks or other
sources of green space and face existing
health disparities. While many coastal cities in
California include expensive beachfront homes,
the coast is used regularly for recreation by
thousands of working class residents who are
visiting or live nearby. Sea-level rise planning
and adaptation strategies should protect public
access to and along the beach to maximize free
or affordable use of the coast for the benefit of
all Californians.
• Prevent displacement by ensuring that
investments in coastal resilience protect local
jobs and housing costs. In climate adaptation
policies, it is important to understand the
economic ties between vulnerable communities
and polluting industries along their coasts,
and how to build environmentally healthy
and economically vibrant communities.

Deindustrialization of coastal areas and
restoration of natural coastal habitats can result
in major environmental benefits, but also job
losses and rent increases for the very same
communities who are intended to be protected
by these natural buffers. Coastal resilience
investments should provide economic benefits
for adjacent working-class communities,
including anti-displacement housing policies
and local jobs programs.
• Address economic impacts on agriculture.

California has major agricultural regions
along the Central Coast - such as the Oxnard
Plain, Santa Maria Valley and Salinas Valley
where tens of thousands of farmworkers are
employed in the fields and whose livelihoods
are threatened by seawater intrusion into
groundwater aquifers. Focused monitoring of
seawater intrusion in coastal agricultural areas,
restoration of coastal wetlands buffers, and
effective groundwater management to prevent
excessive pumping and restore groundwater
could help prevent major long-term economic
damage to agriculture and farmworkers.
• Address emergency services and response
to natural disasters. Low-income, immigrant
communities and other vulnerable populations
are often left behind in access to information
and resources in the chaos of disaster response.

Proactive, deliberate planning in partnership
with marginalized communities can prevent
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STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
this type of systemic failure in the event
of a flooding disaster. Emergency services
agencies should be prepared to translate
print and online communications and create a
more comprehensive vulnerable communities
emergency response plan through stakeholder
engagement. Known information about future
flooding risks should be made easily available
in all commonly-spoken local languages and in
visual form.
• Evaluate the social and economic implications
of various adaptation strategies. Planning and
investment decisions that will increase risk to
vulnerable communities should be avoided, and
actions to bolster resilience and social equity
should be prioritized.

2. Adaptation strategies should prioritize
protection of coastal habitats and public access.
• Implement natural solutions for shoreline
protection, including managed retreat.

Strategies to protect shoreline development
from sea-level rise impacts should prioritize the
use of natural infrastructure where feasible or
appropriate and minimize shoreline armoring
and flood barriers. While hard structures or gray
solutions provide temporary protection against
the threat of sea-level rise, they disrupt natural
shoreline processes, accelerate long-term
erosion, may increase wave and storm run-up,
and can prevent coastal habitats from migrating
inland, causing loss of beaches and other
critical habitats that provide ecosystem benefits
for both wildlife and people; therefore, they
should only be used in appropriate locations
and situations. There is a breadth of resources
available to guide the implementation of natural
solutions including a recently released report,
“Case Studies of Natural Shoreline Infrastructure
in Coastal California”37 as part of California’s
Fourth Climate Change Assessment.

Natural shoreline infrastructure means utilizing
the natural function of ecological systems or
processes to reduce vulnerability to specific

37. http://scc.ca.gov/files/2017/11/tnc_Natural-Shoreline-Case-Study_hi.pdf environmental hazards and increase resilience of
the shoreline in order to perpetuate or restore
its ecosystem services.38 Natural infrastructure
includes preservation or restoration of dunes,
wetlands and other coastal habitats and
leverages natural processes to reduce risk to
human lives, property and infrastructure by
providing a buffer against storm surge and
increased wave action, thus reducing shoreline
impacts and coastal erosion. These solutions
have been shown in many cases to be low
maintenance, cost-effective and adaptive to
changing conditions. Additionally, natural
infrastructure provides multiple benefits beyond
flood protection including public access, habitat
for wildlife and improved water quality, thereby
building resilience while improving overall
ecological function of coastal systems.

In addition to prioritizing natural infrastructure,
managed retreat should be considered as a
possible adaptation strategy to address rising
sea levels. Managed retreat refers to varying
approaches to managing coastal hazard risk
by structure relocation and/or abandonment
of land.39 These strategies can result in a
landward redevelopment pattern and a managed
realignment of development along the coast so
that natural erosion and other coastal processes,
including beach formation and creation, can
continue. Managed retreat allows shorelines
to migrate inland naturally, rather than using
seawalls, flood barriers, or rock revetments to
anchor them in a specific location. This strategy
may involve removal or relocation of residential,
commercial, or industrial development and
restoration of natural areas to enhance
ecosystem services, make sound infrastructure
investments, and provide additional protection
and safety against flooding through buffering
effects, as described above.

38. Newkirk, S, S. Veloz, M. Hayden, W. Heady, K. Leo, J. Judge, R. Battalio, T. Cheng, T. Ursell, and M. Small. (The Nature Conservancy and Point Blue Conservation Science). 2018. Toward Natural Infrastructure to Manage Shoreline Change in California. California’s Fourth Climate Change Assessment, California Natural Resources Agency. Publication number: CNRA-CCC4A-2018-3B. Expected release August 2018.

39. Hino, M., Field, C.B. and Mach, K.J., 2017. Managed retreat as a response to natural hazard risk. Nature Climate Change. https://www.nature.com/articles/nclimate3252.

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STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
Managed retreat will also provide added
protection for wetlands, marshes and other
important coastal habitats that will face
inundation or erosion if restricted from moving
landward by existing development or shoreline
armoring. Decision makers should prioritize
conservation, restoration and land acquisition
of properties that can provide needed open
space to accommodate inland migration in order
to preserve the natural function of wetlands and
other coastal ecosystems.

Restoration of wetlands and other coastal
habitats should remain a priority in California
even in the face of rising seas; even if presentday restored wetlands transition to subtidal habitat sometime in the future, there will still be
continued ecosystem benefits for wildlife and
people over the long term. In addition, wetland
restoration and other adaptation strategies that
provide greenhouse gas reduction benefits by
storing and sequestering carbon should
be prioritized.
• Preserve public access, including beaches
and coastal parks, while protecting natural
resources. Public access along California’s
coast is already being affected by sea-level rise,
coastal flooding, and erosion. Coastal trails,
public beaches, park infrastructure, and other
state and public assets that are of high value
to Californians will increasingly be under threat
from higher sea levels, intensified wave action,
and accelerated coastal erosion.

Decision makers, including state and local
agencies that manage state- or locally-owned
coastal assets, should assess the vulnerability
of public access and prioritize its protection for
the invaluable benefits it provides to residents
and visitors. Every effort should be made to
ensure that protection of public access or
park infrastructure does not degrade coastal
habitats. Beaches backed by development or
shoreline armoring will not be able to migrate
inland as sea levels rise, resulting in permanent
inundation over time and loss of public access.

Consideration should be given to allowing
for natural shoreline retreat and relocation
of public access and park infrastructure to
preserve beach access and protect wetlands,
dunes and other coastal habitats. Using natural
infrastructure to safeguard public access
facilities, parks, and trails or planning ahead to
relocate these resources will help ensure that
both public access and coastal habitats are
preserved for the long-term.

3. Adaptation strategies should consider the
unique characteristics, constraints and values of
existing water-dependent infrastructure, ports and
Public Trust uses.

Existing water-dependent infrastructure and ports
support Public Trust uses vital to the State (such
as commerce, navigation, fisheries, and recreation)
and have unique characteristics and constraints for
adaptation to sea-level rise. They are often located
in densely developed coastal areas where managed
retreat, natural infrastructure solutions, and other
space-dependent strategies may not be feasible.

Planners should continue to collaborate regionally
and with the State to develop adaptation strategies
for water-dependent infrastructure that will be
protected in place, as well as address strategies
to adapt existing infrastructure into the future.

Existing shoreline protective structures may need
to be repaired and retrofitted to adapt to rising
sea levels. Negative impacts to other Public Trust
values, including coastal habitats and public access,
should be minimized in all existing and future use
of shoreline protective structures. Innovative and
resilient design alternatives to conventional grey
infrastructure should be explored when retrofitting
existing protective structures or contemplating
future protective structures.

4. Consider episodic increases in sea-level rise
caused by storms and other extreme events.

Future sea-level rise projections presented in
this Guidance do not include acute increases in
water level associated with El Niño events, king
tides, storm surges or large waves. Alone or in
combination, these events will produce significantly
higher water levels than sea-level rise alone, and
will likely be the drivers of the strongest impacts
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STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
to coastal ecosystems, development and public
access over the next several decades. Water levels
reached during these large, acute events have
already caused significant damage along California’s
coast. For example, a strong El Niño combined with
a series of storms during high-tide events caused
more than $200 million in damage (in 2010 dollars)
to the California coast during the winter of 1982

83. Additionally, in areas where rivers meet the
ocean, the combined effects of sea-level rise, storm
conditions and higher riverine water levels could
further exacerbate flooding conditions in these
locations.

Furthermore, climate change may result in
increased frequency or intensity of coastal storms
and extreme events, posing even greater risks
for California’s coastline from flooding, erosion
and wave damage. To adequately protect coastal
communities, infrastructure and natural resources,
decision makers should consider extreme
oceanographic conditions in conjunction with
sea-level rise over the expected life of a project.

A range of existing mapping tools is available to
help evaluate storm-related coastal flooding, sealevel rise and shoreline change and to evaluate impacts and change into the future; these mapping
tools are described in detail below. In addition to
these tools, the San Francisco Bay Conservation and
Development Commission’s (BCDC) Adapting to
Rising Tides (ART) Program has developed robust
and locally-relevant for the San Francisco Bay to
understand current and future flood risk.40 It is
important to note that current Federal Emergency
Management Agency (FEMA) flood maps are based
on existing shoreline characteristics and wave and
storm climatology at the time of the flood study and
historic storm data; therefore, these maps will not
reflect flood hazards based on anticipated future
sea levels or increased storms associated with
climate change.41

40. www.adaptingtorisingtides.org

41. https://www.fema.gov/coastal-frequently-asked-questions#How is FEMA accounting for sea level rise and climate change on the FIRMs? Does sea level rise/climate change affect the FIRMs?

5. Coordinate and collaborate with local, state
and federal agencies when selecting sea-level rise
projections; where feasible, use consistent sealevel rise projections across multi-agency planning and regulatory decisions.

Project planning and design along the coast often
requires approval by multiple agencies across
local, regional, state and federal levels. To increase
efficiency and standardize risk evaluation, efforts
led by or under the regulatory authority of multiple
agencies should use the same sea-level rise
projections to achieve consistency across specific
projects and regions. Cross-jurisdictional decisions
should also prioritize implementation of consistent
or complementary adaptation strategies.

6. Consider local conditions to inform
decision making.

Local circumstances and associated sea-level rise
impacts should be assessed to inform adaptation
decisions that will protect communities and the
environment. The interplay between sea-level rise and
conditions such as contaminated soil, groundwater,
or stormwater systems as well as beach and cliff
erosion can vary significantly along the coast and
should be evaluated at a local level. The diversity
of shoreline types, natural conditions, community
characteristics, services, assets, land ownership, and
local priorities may warrant different approaches to
planning and adaptation, particularly when making
decisions for new development versus maintenance
or replacement of existing assets necessary for public
health and safety. Adaptation pathways with a phased
approach can invoke the precautionary principle
while maintaining protection of community wellbeing, the environment, and critical assets.

7. Include adaptive capacity in design
and planning.

Uncertainty around the magnitude and timing of
future sea-level rise, coupled with the potential
impacts of rising seas on California’s coastline,
warrant a proactive approach that builds adaptive
capacity into project design and planning. Projects
or resources that can more easily adapt to sea-level
rise will experience fewer consequences and will be
RECOMMENDATIONS FOR SEA-LEVEL RISE PLANNING AND ADAPTATION | 32

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
more resilient against risks associated with sea-level
rise and other coastal climate-related impacts.

If designing a project to accommodate high or
extreme sea-level rise is not critical in the near term, but the likelihood of impacts is expected to increase
with rising sea level, adaptive capacity should be
built into project design or planning using triggers
and phased adaptation measures or adaptation
pathways, as described in Step 5 above. Triggers
are predetermined thresholds that, when crossed,
prompt implementation of identified adaptation
measures. For example, one trigger mechanism
could require that, when sea-level rise reaches a
certain level, identified adaptive measures must be
taken. Alternatively, the occurrence of a specific
impact such as the flooding of a highway could
act as a trigger. An increase in the frequency of a
specific sea-level rise-associated impact, such as the
flooding of a coastal trail ten times in a year rather
than a historically traditional three times a year, also could be a trigger.

Adaptation measures may include, but are not
limited to, removal of threatened structures
(including identification of parties responsible for
removal) or relocation of public access. Triggerbased adaptation planning may also include the following approaches: 1) a no-regrets response,
involving prohibition or restriction of development in
the most vulnerable areas; 2) a tempered response,
involving restriction or changing conditions for
redevelopment after an event; and 3) a proactive
response, involving investigation of opportunities
to relocate vulnerable communities, critical
infrastructure or coastal habitats.

Providing adaptive capacity for higher sea-level
rise will allow projects to be designed for a more
moderate level of sea-level rise but planned with
enough flexibility that adaptation measures to
minimize impacts can be implemented if the amount
of sea-level rise is higher than anticipated in the
original design. In other words, projects should be
scoped (planned and designed) with the potential
to be updated or changed if lower-probability,
higher-impact sea level rise projections come to
occur. Design and planning efforts that include
a trigger-based adaptation pathways approach
should include a monitoring component to ensure
timely implementation of adaptation or contingency
measures once impact or risk thresholds are crossed.

8. Assessment of risk and adaptation planning
should be conducted at community and regional
levels, when possible.

Sea-level rise planning decisions made for one
municipality, or even one landowner, have the
potential to impact the resiliency of nearby
properties and coastal habitats. A jurisdiction that
chooses to implement natural infrastructure may
lose some of the benefits and protection from
this adaptation strategy if an adjacent community
decides to construct a seawall. Decision makers
should identify opportunities to coordinate
regional adaptation planning efforts by: conducting
regional vulnerability assessments to evaluate
common risks; leveraging technical and financial
resources; and implementing consistent regional
adaptation strategies. BCDC’s ART Program and
the San Diego Regional Climate Collaborative42
are examples of regional planning efforts that can
serve as models for other regional planning efforts
throughout the state.

42. https://www.sdclimatecollaborative.org
RECOMMENDATIONS FOR SEA-LEVEL RISE PLANNING AND ADAPTATION | 33 Tools Available to Visualize

Sea-Level Rise Spatially

THERE ARE SUITES OF EXISTING

GEOSPATIAL AND VISUALIZATION TOOLS
that can be readily paired with the latest and best
available sea-level rise projections. These include
CoSMoS/Our Coast Our Future,43,44 the NOAA
Sea-Level Rise Viewer,45 Cal-Adapt,46 The Nature
Conservancy (TNC) Coastal Resilience Toolkit47
and Surging Seas Risk Finder.48 Each viewer serves
a unique niche, target audience and role, has
strengths and limitations, and requires varying
levels of skill to use. More information on these
tools can be found on Sea the Future49 (formerly
known as Lifting the Fog) and on the State

43. https://walrus.wr.usgs.gov/coastal_processes/cosmos/

44. http://data.pointblue.org/apps/ocof/cms/

45. https://coast.noaa.gov/digitalcoast/tools/slr

46. http://cal-adapt.org/

47. http://coastalresilience.org/

48. https://riskfinder.climatecentral.org/

49. http://sealevel.climatecentral.org/matrix/CA.html?v=1 Adaptation Clearinghouse. In addition to assisting
in the visualization and analysis of sea-level rise,
these tools are also helpful aids in communicating
about sea-level rise across local, state, and regional
communities and planning and decision-making
venues. In general, we recommend that the most
detailed tool available for a particular area be used
for planning, though in some cases a suite of tools
should be evaluated to get a better picture of the
possible risks.
• CoSMoS is a model that has been developed
by the United States Geological Survey (USGS)
in order to allow for more detailed predictions
of coastal flooding due to both future sealevel rise and storms integrated with longterm coastal evolution (i.e., beach changes and cliff/bluff retreat) over large geographic
areas. CoSMoS models the relevant physics
of a coastal storm (e.g., tides, waves, and
TOOLS AVAILABLE TO VISUALIZE SEA-LEVEL RISE SPATIALLY | 34

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
storm surge), which are then scaled down to
local flood projections for use in communitylevel coastal planning and decision-making.

Rather than relying on historic storm records,
CoSMoS uses wind and pressure from global
climate models to project coastal storms
under changing climatic conditions during
the 21st century. CoSMoS projections are
currently available for the north-central coast,
San Francisco Bay, and Southern California.

Modeling is underway for the Central Coast, to
be completed in summer 2018. The North Coast
of California is expected to be complete by the
end of 2019. CoSMoS information can also be
accessed, viewed, and downloaded through the
Our Coast, Our Future (OCOF) flood mapper,
which provides a user-friendly web-based tool
for viewing results. OCOF provides resources
and guidance for helping communities navigate
the information provided by CoSMoS.
• The NOAA Sea-Level Rise Viewer is a
visualization tool for coastal communities
showing the potential impacts from sealevel rise and coastal flooding. The NOAA Viewer allows users to select the nearest
NOAA tide gauge and identify relative sealevel rise scenarios based on the NOAA 2017 Technical Report50, which includes the federal
government’s most updated scenarios that will
inform the Fourth National Climate Assessment.

These scenarios are similar to the probabilistic
ranges for California. The tool allows users to
visualize inundation by scenario or year and
explore thresholds for levee overtopping. It also
includes the ability to look at flood frequency,
marsh migration, socio-economic impacts, and
uncertainty. The maps consider static sealevel rise on top of mean higher high water51 (MHHW) and are created using a “modified”
bathtub approach that includes a hydrologic
connectivity assessment. This means that

50. https://tidesandcurrents.noaa.gov/publications/techrpt83_Global_and_Regional_SLR_ Scenarios_for_the_US_final.pdf

51. California experiences semidiurnal tides, with two high tides and two low tides each day. One of the two high tides is higher than the other and one of the two low tides is lower than the other. Mean higher high water is the average of the higher high tides over the National Tidal Data Epoch. https:// tidesandcurrents.noaa.gov/datum_options.html
areas are only shown as inundated if there is a
feasible pathway for water to flow. The viewer
is a screening-level, planning tool that uses
nationally consistent data sets and analyses.

Data and maps can be downloaded directly
from the tool to enable users to develop
their own visualizations to gauge trends and
prioritize actions.
• Cal-Adapt makes scientific projections and
analyses available as a basis for understanding
local climate risks and resilience options. To
date, development has been supported by the
California Energy Commission and has targeted
resilience needs of the energy sector. Released
in 2017, Cal-Adapt 2.0 dramatically expands
the capacities of the initial (2011) version of
Cal-Adapt in five main ways, providing new
climate projections, more powerful and flexible
visualizations, improved access to data, a public
applications programming interface (API)
platform that enables external development of
custom tools, and connection with supporting
resources such as OPR’s Integrated Climate
Adaptation and Resiliency Program (ICARP).

Forthcoming enhancements to Cal-Adapt will
expand its sea-level rise tool to include selected
results from USGS’s CoSMoS model (portrayed
in detail by the Our Coast, Our Future tool)
as well as an expanded range of sea-level rise
projections for which UC Berkeley has modeled
inundation associated with an extreme storm
event for the Delta, San Francisco Bay, and the
entire California coast.
• The Nature Conservancy Coastal Resilience
tool is a visualization and decision support
platform where ecological, social, and economic
information can be viewed alongside sea-level
rise and storm surge scenarios to develop
risk reduction and restoration solutions. The
decision support tool was first created in 2008
and now covers multiple regions including: 10
U.S. States (Alabama, California, Connecticut,
Florida, Louisiana, Mississippi, New Jersey,
New York, Texas, Washington), four countries
in Latin America (Mexico, Belize, Guatemala,
Honduras) and three island nations in the
TOOLS AVAILABLE TO VISUALIZE SEA-LEVEL RISE SPATIALLY | 35

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
Caribbean (Grenada, St. Vincent and the
Grenadines, U.S Virgin Islands). There also is
a U.S. national and global application. Coastal
Resilience 2.0 was released in October 2013 to
better enable decision makers to assess risk and
identify nature-based solutions to reduce socioeconomic vulnerability to coastal hazards. The purpose of the tool is to inform county hazard
mitigation planning. Its intended uses are to:
1) raise awareness of coastal hazards issues;
2) examine local flood risk; and 3) identify
potential adaptation solutions.
• Surging Seas Risk Finder is a multi-part public
web tool that provides local sea-level rise and
flood risk projections, interactive maps, and
exposure tabulations from zip codes and up.

Projections integrate extreme flood statistics
with dozens of sea-level rise models and
scenarios to choose from. Maps are based on
the same modified bathtub model used by
NOAA’s Sea-Level Rise Viewer and consider
static sea-level rise up to 10 feet above mean
higher high water (MHHW). Maps illustrate
which areas are or are not hydrologically
connected to the ocean at each one-foot
increment, and have layers for population,
social vulnerability, property value, point
features and more. Exposure assessments
tabulate over 100 demographic, economic,
infrastructure and environmental variables
for every zip code and municipality, as well
as planning, legislative and other districts.

Additional features include heat maps showing
wide-area exposure comparisons, and extensive
data downloads including localized fact sheets,
reports, and PowerPoint slides. Tutorial videos
and step-by-step guides are also available.52
52 . http://sealevel.climatecentral.org/ssrf/help-page
TOOLS AVAILABLE TO VISUALIZE SEA-LEVEL RISE SPATIALLY | 36

Conclusion

EXACT RATES AND MAGNITUDE OF

SEA-LEVEL RISE IN CALIFORNIA
over the next century are uncertain, though
the direction of change is not. California has an
immediate opportunity to make smart, informed,
and risk-based decisions that prepare our coastal
and inland communities for change while ingraining
sustainability, longevity, and resiliency into our
planning, permitting, investment, development,
transportation, and recreational decisions. This
Guidance document serves as a precautionary,
though realistic and scientifically rigorous,
recommendation on how best to approach sealevel rise in California no matter the decision at hand. The Guidance should be considered and cited
throughout local, regional, and statewide sea-level
rise discussions and decisions. And while sea-level
rise science is rapidly evolving, the Guidance was
prepared so that it can be a living document and
swiftly updated as needed and recommended.

Depending on the time or planning horizon being
considered, different sources of uncertainty (i.e.,
emission scenario or model uncertainty) play
smaller or bigger roles in projections of sea-level
rise. For example, as we consider the more distant
future and our ability to predict what society will
do lessens, different models will be more or less
dependable, and the processes generating or driving
the extreme sea-level rise scenarios will unfold. This
uncertainty is why the State included the extreme
sea-level rise scenario but did not assign a likelihood or probability to this scenario. Similarly, it is worth explicitly noting that probabilistic projections need
to be taken as an evolving representation of the
scientific field, open to updates and modifications.

In this context of continued and unquantifiable
uncertainties, incorporating long-range planning for
sea-level rise in decisions is increasingly urgent. We
know we will experience significant increases in sealevel rise, though it remains a challenge to say when this will occur and with what level of confidence it
will occur in the given timeframe. This is precisely
why it is critical to plan now for a range of
possibilities, and integrate these possible futures in
planning and preparing across specific communities.

CONCLUSION | 37

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
This risk-based approach outlined in the Guidance, with consideration of the full range of outcomes including potentially consequential outcomes with low probability of occurrence, is consistent with standard practice across risk-centered fields.

California’s state agencies and local jurisdictions along the coast and inland Delta are taking action to assess the risks and reduce the anticipated short and longterm impacts of climate change. Steps to incorporate sea-level rise in planning and investment decisions must be taken at the local and State levels to be appropriately relevant, precautionary, agile and progressive. This Guidance serves to increase our understanding of risks as they relate to sea-level rise and apply a set of principles so we are as adaptive and responsive as possible. While the Guidance currently pertains mostly to the coast, it is critical that we consider inland impacts of sea-level rise for long-term planning and follow the same set of recommendations and principles beyond the immediate coastal zone. For future updates to the Guidance, we will incorporate inland sea-level rise modelling and projections to the extent they are available and based on rigorous and peer-reviewed science.

This Guidance, accompanied by a set of resources provided on the State’s Adaptation Clearinghouse and OPC’s website, serves to be a living tool and resource for state and local planners, decision makers, and stakeholders. It is deliberately structured to be both precautionary and flexible with a core set of recommendations and principles that can readily infuse new scientific approaches and methods to sealevel rise projections as they arise. This adaptability and commitment to actionable science is what will ensure that California is prepared and responsive to the host of changes to come.

Finally, in developing this Guidance, the State took intentional action to engage users and decision makers to ensure that the scientific information and policy direction was understandable and useful for sea-level rise planning and adaptation efforts.

There is a continued need for ongoing coordination and collaboration across state, regional and local entities to guarantee effective implementation this Guidance. Going forward, OPC will continue to prioritize opportunities for co-production of future decision-support products by scientists, practitioners, and policy and decision makers to further improve the translation of sea-level rise science into action.

CONCLUSION | 38
Glossary
ADAPTATION (climate change): Adjustment in
natural or human systems to a new or changing
environment. Adaptation to climate change refers to
adjustment in natural or human systems in response
to actual or expected climatic stimuli or their
effects, which moderates harm or exploits beneficial
opportunities.53
ADAPTATION PATHWAY: An adaptation pathway
is a planning approach addressing the uncertainty
and challenges of climate change decision-making.

It enables consideration of multiple possible futures,
and allows analysis/exploration of the robustness
and flexibility of various options across those
multiple futures.54
ADAPTIVE MANAGEMENT: A process of
iteratively planning, implementing, and modifying
strategies for managing resources in the face of
uncertainty and change. Adaptive management
involves adjusting approaches in response to
observations of their effect and changes in the
system brought on by resulting feedback effects and
other variables.55
ADAPTIVE CAPACITY: The ability of a system
to respond to climate change (including climate
variability and extremes), to moderate potential
damages, to take advantage of opportunities, and to
cope with the consequences.56

53. Glossary of Climate Change Terms. Office of Air and Radiation/Office of Atmospheric Programs/Climate

Change Division. September 9, 2013: https://19january2017snapshot.epa.gov/climatechange_.html

54. South West Climate Change Portal: Catchment Planning - Using Adaptation Pathway:

http://www.swclimatechange.com.au/cb_pages/adaptation_pathways.php

55. IPCC Climate Change 2014: Impacts, Adaptation, and Vulnerability http://www.ipcc.ch/pdf/assessmentreport/ar5/wg2/WGIIAR5-AnnexII_FINAL.pdf

56. Willows RI, RK Connell (eds.). 2003. Climate Adaptation: Risk, Uncertainty and Decisionmaking. UKCIP Technical Report. Oxford: UKCIP. 154 pp. http://www.ukcip.org.uk/wordpress/wp-content/PDFs/UKCIP-Risk-framework.pdf CLIMATE CHANGE: Climate change refers to
a change in the state of the climate that can be
identified by changes in the mean and/or the
variability of its properties, and that persists for
an extended period, typically decades or longer.

Climate change may be due to natural internal
processes or external forcings such as modulations
of the solar cycles, volcanic eruptions, and persistent anthropogenic changes in the composition of the
atmosphere or in land use.57
COMMUNITY RESILIENCE: Community resilience
is the ability of communities to withstand, recover,
and learn from past disasters to strengthen future
response and recovery efforts. This can include but
is not limited to physical and psychological health of
the population, social and economic equity and wellbeing of the community, effective risk communication, integration of organizations (governmental and
nongovernmental) in planning, response, and
recovery, and social connectedness for resource
exchange, cohesion, response, and recovery.58
DISADVANTAGED COMMUNITIES: Areas
disproportionately affected by environmental
pollution and other hazards that can lead to negative
public health effects, exposure, or environmental
degradation, or with concentrations of people
that are of low income, high unemployment,
low levels of homeownership, high-rent burden,
sensitive populations, or low levels of educational
attainment.59

57. IPCC Climate Change 2014: Impacts, Adaptation, and Vulnerability https://www.ipcc.ch/report/ar5/wg2/

58. Los Angeles County Community Disaster Resilience: http://www.laresilience.org/resources/glossary.php

59. California Health and Safety Code Section 39711: http://www.leginfo.ca.gov/pub/11-12/bill/sen/sb_0501 0550/sb_535_bill_20120910_enrolled.html
GLOSSARY | 39

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
EMISSIONS SCENARIOS: Scenarios representing
alternative rates of global greenhouse gas
emissions growth, which are dependent on rates of
economic growth, the success of emission
reduction strategies, and rates of clean technology
development and diffusion, among other factors.60
ENVIRONMENTAL JUSTICE: The structures,
policies, practices, and norms resulting in differential access to the goods, services, and opportunities
of society by “race.” It is normative, sometimes
legalized, and often manifests as inherited
disadvantage. Examples include differential access
to quality education, sound housing, gainful
employment, appropriate medical facilities, and a
clean environment (Gov. Code §65040.12[e]).

EQUITY: Equity is just and fair inclusion into a
society in which all can participate, prosper, and
reach their full potential.61
EQUITY (climate): The central equity challenges
for climate change policy involve several core issues:
addressing the impacts of climate change, which
are felt unequally; identifying who is responsible for
causing climate change and for actions to limit its
effects; and understanding the ways in which climate
policy intersects with other dimensions of human
development, both globally and domestically.62
EXTREME (climate) EVENTS: The occurrence of
a value of a weather or climate variable above (or
below) a threshold value near the upper (or lower)
ends of the range of observed values of the variable.63 GLOBAL CLIMATE MODELS: A numerical
representation of the climate system that is based
on the physical, chemical, and biological properties
of its components, their interactions, and feedback
processes, and that accounts for all or some of its
known properties.64

60. Bedsworth L, E Hanak. 2008. Preparing California for a Changing Climate. PPIC Research Report. Public Policy Institute of California. San Francisco, USA. http://www.ppic.org/content/pubs/report/R_1108LBR.pdf

61. PolicyLink: http://www.policylink.org/

62. World Resources Institute. Building Climate Equity: Creating a New Approach from the Ground Up. July 2014. https://www.wri.org/sites/default/files/building-climate-equity-072014.pdf

63. Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation. IPCC, 2012. http:// www.ipcc.ch/pdf/special-reports/srex/SREX_Full_Report.pdf

64. IPCC, 2012: Glossary of terms. In: Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation. https://www.ipcc.ch/pdf/special-reports/srex/SREX-Annex_Glossary.pdf INTEGRATED CLIMATE ACTIONS: Program,
plans, or policies that simultaneously reduce
greenhouse gas emissions and decrease the risks
posed by climate change on the system where the
action is implemented.

MITIGATION (climate change): A human
intervention to reduce the human impact on the
climate system; it includes strategies to reduce
greenhouse gas sources and emissions and
enhancing greenhouse gas sinks.65
MITIGATION (of disaster risk and disaster):

The lessening of the potential adverse impacts of
physical hazards (including those that are humaninduced) through actions that reduce hazard, exposure, and vulnerability.66
NATURAL & GREEN INFRASTRUCTURE:

Natural infrastructure means utilizing the natural
function of ecological systems or processes to
reduce vulnerability to specific environmental
hazards and increase resilience of the shoreline
in order to perpetuate or restore its ecosystem
services.67

REPRESENTATIVE CONCENTRATION
PATHWAYS: Representative Concentration
Pathways (RCPs) are four greenhouse gas
concentration (not emissions) trajectories adopted
by the IPCC for its Fifth Assessment Report in 2014.

The Representative Concentration Pathways (RCPs),
which are used for making projections based on
these factors, describe four different 21st century
pathways of GHG emissions and atmospheric
concentrations, air pollutant emissions and land use.

The RCPs include a stringent mitigation scenario
(RCP2.6), two intermediate scenarios (RCP4.5
and RCP6.0) and one scenario with very high GHG
emissions (RCP8.5).68

65. Glossary of Climate Change Terms. Office of Air and Radiation/Office of Atmospheric Programs/Climate Change Division. September 9, 2013. https://www.epa.gov/climatechange

66. IPCC Climate Change 2014: Impacts, Adaptation, and Vulnerability. https://www.ipcc.ch/report/ar5/wg2/

67. Newkirk, S, S. Veloz, M. Hayden, W. Heady, K. Leo, J. Judge, R. Battalio, T. Cheng, T. Ursell, and M. Small. (The Nature Conservancy and Point Blue Conservation Science). 2018. Toward Natural Infrastructure to Manage Shoreline Change in California. California’s Fourth Climate Change Assessment, California Natural Resources Agency. Publication number: CNRA-CCC4A-2018-3B. Expected release August 2018.

68. IPCC, 2014: Climate Change 2014: Synthesis Report. https://www.ipcc.ch/pdf/assessment-report/ar5/syr/ SYR_AR5_FINAL_full_wcover.pdf
GLOSSARY | 40

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
RESILIENCE (climate): Resilience is the capacity
of any entity – an individual, a community, an
organization, or a natural system – to prepare for
disruptions, to recover from shocks and stresses, and
to adapt and grow from a disruptive experience.69
RISK: Commonly considered to be the combination
of the likelihood of an event and its consequences
– i.e., risk equals the probability of climate hazard
occurring multiplied by the consequences a given
system may experience.70
RISK AVERSION: The strong inclination to avoid
taking risks in the face of uncertainty.

RISK TOLERANCE: A community’s or decision
maker’s willingness to accept a higher or lower
probability of impacts.71
SCENARIO-BASED ANALYSIS: A tool for
developing a science-based decision-making
framework to address environmental uncertainty.

In general, a range of plausible impacts based on
multiple time scales, emissions scenarios, or other
factors is developed to inform further decisionmaking regarding the range of impacts and vulnerabilities.72
SEA-LEVEL RISE: The worldwide average rise in
mean sea level, which may be due to a number of
different causes, such as the thermal expansion of
sea water and the addition of water to the oceans
from the melting of glaciers, ice caps, and ice sheets; contrast with relative sea-level rise.73

69. Rodin, Judith. 2014. The Resilience Dividend: Being Strong in a World Where Things Go Wrong.

Philadelphia: Perseus Books Group (pages 3-4).

70. Burton I, E Malone, S Huq. 2004. Adaptation Policy Frameworks for Climate Change: Developing Strategies, Policies and Measures. [B Lim, E Spanger-Siegfried (eds.)]. United Nations Development Programme. Cambridge University Press: Cambridge, New York, Melbourne, Madrid. 258 pp. https://www.preventionweb.net/files/7995_APF.pdf

71. Parris A, P Bromirski, V Burkett, D Cayan, M Culver, J Hall, R Horton, K Knuuti, R Moss, J Obeysekera, A Sallenger, J Weiss. 2012. Global Sea-level Rise Scenarios for the US National Climate Assessment. NOAA Tech Memo OAR CPO-1. 37 pp. http://scenarios.globalchange.gov/sites/default/files/NOAA_SLR_r3_0.pdf

72. National Oceanic and Atmospheric Administration (NOAA). 2010. Adapting to Climate Change: A Planning Guide for State Coastal Managers. NOAA Office of Ocean and Coastal Resource Management. 138pp. http:// coastalmanagement.noaa.gov/climate/docs/adaptationguide.pdf

73. Glossary of Climate Change Terms. Office of Air and Radiation/Office of Atmospheric Programs/Climate Change Division. September 9, 2013. https://19january2017snapshot.epa.gov/climatechange_.html VULNERABILITY: The propensity or predisposition
to be adversely affected. Vulnerability encompasses
a variety of concepts and elements including
sensitivity or susceptibility to harm and lack of
capacity to cope and adapt.74
VULNERABILITY ASSESSMENT: A practice that
identifies who and what is exposed and sensitive
to change and how able a given system is to cope
with extremes and change. It considers the factors
that expose and make people or the environment
susceptible to harm and access to natural and
financial resources available to cope and adapt,
including the ability to self-protect, external coping
mechanisms, support networks, etc.75
VULNERABLE POPULATIONS: Vulnerable
populations include, but are not limited to women;
racial or ethnic groups; low-income individuals and
families; individuals who are incarcerated or have
been incarcerated; individuals with disabilities;
individuals with mental health conditions; children;
youth and young adults; seniors; immigrants and
refugees; individuals who are limited English
proficient (LEP); and Lesbian, Gay, Bisexual,
Transgender, Queer, and Questioning (LGBTQQ)
communities, or combinations of these populations.76

74. IPCC Climate Change 2014: Impacts, Adaptation, and Vulnerability. https://www.ipcc.ch/report/ar5/wg2/

75. Tompkins, E, S. Nicholson-Cole, L. Hurlston, E. Boyd, G. Hodge, J. Clarke , G. Gray, N. Trotz, L. Varlack. 2005.

Surviving Climate Change in Small Islands – A guidebook. https://www.preventionweb.net/files/734_10365.pdf

76. California Health and Safety Code Section 131019.5 https://www.cdph.ca.gov/Programs/OHE/CDPH%20 Document%20Library/Health_and_Safety_Code_131019.5.pdf
GLOSSARY | 41

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 1:

Guidance Document Development

THE PURPOSE OF THE 2018 UPDATE TO
THE STATE’S SEA-LEVEL RISE GUIDANCE
(Guidance) was to reflect recent advances in ice
loss science and projections of sea-level rise and
focus on the needs of state agencies and local
governments as they incorporate sea-level rise into
their planning, permitting and investment decisions.

The development of the Guidance update included
three components: 1) a science synthesis to reflect
the latest advances in sea-level rise science; 2) a
robust public outreach and engagement effort to
ensure the updated Guidance is understandable and
useful for decision making; 3) and integration of
components 1 and 2 to create a science-based, userinformed policy document.

Updating the Science.

Ocean Science Trust (OST), with support from the
Ocean Protection Council (OPC), led the scientific
component of the update and convened an OPC
Science Advisory Team (OPC-SAT) Working
Group. The Working Group members, who have
subject-matter experts in coastal processes, risk
assessment, climatic change, ice loss and ice sheet
behavior, and statistical modeling, included: Gary
Griggs, University of California Santa Cruz, OPCSAT (Working Group Chair); Dan Cayan, Scripps Institution of Oceanography, OPC-SAT; Robert
Kopp, Rutgers University; Claudia Tebaldi, National
Center for Atmospheric Research; Helen Fricker,
Scripps Institution of Oceanography; Joe Arvai,
University of Michigan; and Rob DeConto, University
of Massachusetts.

To ensure that the science synthesis could provide a
foundation for policy decisions made in the updated
Guidance, a Policy Advisory Committee (PAC)
comprised of OPC, the California Natural Resources
Agency, the Governor’s Office of Planning and
Research, and the California Energy Commission
developed a list of questions to elicit information
about the current estimates of SLR for California
and how to understand the scientific context around
those estimates. The full list of PAC questions can
be found in Appendix 5.

Using the PAC questions as a guide, the working
group compiled and reviewed the latest climate
research, including the implications of recent
scientific advances on ice loss dynamics for updating
sea-level rise projections and provided a summary of
key findings along with updated projections for three
representative tide gauges in California. This science
summary, entitled “Rising Seas in California: An
Update on Sea-Level Rise Science,” was presented
to the California Ocean Protection Council at its
April 2017 meeting, where the Council then adopted
a resolution77 acknowledging the report as the best
available science on which the updated Guidance
should be based and directing OPC staff to engage
in an inclusive public engagement process to share
the scientific findings and solicit feedback on how
the updated guidance document will be used.

Public Outreach and Engagement.

Input from users of the guidance document was
solicited at multiple points throughout the update
process. In February, March and April 2017, an
engagement team led by Susanne Moser Research
& Consulting and Climate Access, a not-for-profit
organization, conducted interviews78 and five
listening sessions to better understand the needs
of those who will use the guidance document. In
addition, throughout the summer 2017, the OPC
and OST, with support from the engagement
team, convened four public workshops with state,
regional, and local stakeholders in Eureka, San

77. Resolution of the California Ocean Protection Council on Updating the State of California Sea-level Rise Guidance Document, Adopted on April 26, 2017: http://www.opc.ca.gov/webmaster/ftp/pdf/agenda_ items/20170426/ADOPTED-SLR-Resolution-20170426.pdf

78. Interviews were conducted with representatives from local, state and federal governments including:

U.S. Geological Survey, San Francisco Bay Conservation and Development Commission, California Coastal Commission, California Coastal Conservancy, Delta Stewardship Council, California Department of Public Health, Department of Water Resources, State Lands Commission, California State Parks, Strategic Growth Council, State Water Resources Control Board, LA Regional Water Quality Control Board, Governor’s Office of Planning and Research, Governor’s Office of Emergency Services, Caltrans; the cities of Eureka, Arcata,Seaside, Santa Monica, Long Beach; Marin and San Mateo counties, and the San Diego Regional Collaborative. Several consulting firms were also interviewed.

APPENDIX 1: GUIDANCE DOCUMENT DEVELOPMENT | 42

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
Francisco, Los Angeles and San Diego. The purpose of these workshops was to share the science findings and to solicit feedback on how stakeholders will utilize the guidance document. Close to 400 coastal stakeholders from city, county, and regional government entities, consulting groups, non-profits, state and federal agencies and tribal representatives provided input that helped shape the framework for the Guidance update and associated web resources.

OPC also coordinated closely with the Sea-Level Rise Coastal Leadership Team (California Coastal Commission, San Francisco Bay Conservation and Development Commission, State Lands Commission, California State Parks, State Coastal Conservancy) and the Coastal and Ocean working group of the State’s Climate Action Team (CO-CAT), an entity comprised of senior level staff from California state agencies with ocean and coastal resource management responsibilities.

Update to Policy Guidance.

Using the Rising Seas Report and the input from public engagement efforts, OPC staff drafted a science-based, user-informed updated Guidance document in coordination with the PAC and Sea-Level Rise Coastal Leadership Team. The draft will be circulated for formal public comment in the fall of 2017, with final adoption by the Ocean Protection Council scheduled for March 2018.

In response to user needs, the policy Guidance will be supported by a library and database of resources to help visualize change, access funding opportunities, gather policy and scientific background related to specific jurisdictions, and in general provide additional support to address a challenge of this nature and magnitude.

This database and library of resources will be available on the State Adaptation Clearinghouse in mid-2018, as well as OPC’s website.

APPENDIX 1: GUIDANCE DOCUMENT DEVELOPMENT | 43
APPENDIX 2:

Map of Tide Gauge Locations

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
Crescent City
North Spit
Arena Cove
Point Reyes
San Francisco
Monterey
Port San Luis
Santa Barbara
Santa Monica
Los Angeles
La Jolla
0 40 80 San Diego 160 Miles
Data provided by NOAA
APPENDIX 2: MAP OF TIDE GAUGE LOCATIONS | 44
Crescent City
North Spit
Arena Cove
Point Reyes
San Francisco
Monterey
Port San Luis
Santa Barbara
Santa Monica
Los Angeles
La Jolla
0 40 80 160 Miles San Diego
Data provided by NOAA

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3:

Sea-Level Rise Projections For All 12 Tide Gauges

TABLE 1: Projected Sea-Level Rise (in feet) for Crescent City Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.1 0.0 - 0.3 0.4 0.5 0.8
2040 0.3 0.1 - 0.4 0.6 0.9 1.4
2050 0.4 0.2 - 0.7 0.9 1.5 2.3
Low emissions 2060 0.4 0.1 - 0.7 1.0 1.8
High emissions 2060 0.6 0.2 - 0.9 1.3 2.1 3.3
Low emissions 2070 0.5 0.1 - 0.9 1.3 2.4
High emissions 2070 0.8 0.4 - 1.2 1.7 2.8 4.5
Low emissions 2080 0.6 0.1 - 1.1 1.6 3.1
High emissions 2080 1.0 0.5 - 1.6 2.2 3.7 5.9
Low emissions 2090 0.7 0.1 - 1.3 1.9 3.9
High emissions 2090 1.2 0.6 - 2.0 2.8 4.7 7.4
Low emissions 2100 0.7 0.1 - 1.5 2.3 4.8
High emissions 2100 1.5 0.7 - 2.5 3.4 5.9 9.3
Low emissions 2110* 0.8 0.2 - 1.5 2.4 5.3
High emissions 2110* 1.5 0.9 - 2.5 3.4 6.2 11.0
Low emissions 2120 0.8 0.1 - 1.7 2.8 6.3
High emissions 2120 1.8 1.0 - 3.0 4.1 7.4 13.1
Low emissions 2130 0.9 0.1 - 1.9 3.2 7.3
High emissions 2130 2.1 1.1 - 3.4 4.8 8.7 15.3
Low emissions 2140 1.0 0.1 - 2.2 3.6 8.4
High emissions 2140 2.3 1.2 - 3.9 5.5 10.1 17.8
Low emissions 2150 1.0 0.0 - 2.4 4.2 9.6
High emissions 2150 2.6 1.3 - 4.4 6.2 11.6 20.6
*Most of the available climate model experiments do not extend beyond 2100. The resulting reduction in model availability causes a small dip in projections between 2100 and 2110, as well as a shift in uncertainty estimates (see Kopp et al. 2014). Use of 2110 projections should be done with caution and with acknowledgement of increased uncertainty around these projections.

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 45 TABLE 2: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in Crescent City
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

CRESCENT CITY - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030
2040 0.3%
2050 3% 0.1%
2060 13% 1% 0.1%
2070 31% 2% 0.4% 0.1% 0.1%
2080 49% 8% 1% 0.4% 0.2% 0.1%
2090 63% 17% 4% 1% 0.4% 0.2% 0.1% 0.1%
2100 72% 30% 9% 3% 1% 1% 0.3% 0.2% 0.1% 0.1%
2150 90% 67% 40% 21% 11% 6% 3% 2% 1% 1%
CRESCENT CITY - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 6% 0.3% 0.1%
2070 13% 1% 0.2% 0.1%
2080 20% 2% 1% 0.2% 0.1% 0.1%
2090 28% 5% 1% 0.4% 0.2% 0.1% 0.1%
2100 36% 8% 2% 1% 0.4% 0.2% 0.1% 0.1% 0.1%
2150 52% 23% 11% 6% 3% 2% 1% 1% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 46

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 3: Projected Average Rate of Sea-Level Rise (mm/year) for Crescent City
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
High emissions 2030 – 2050 3.8 1.6 - 6.4 8.6 14 23
Low emissions 2060 - 2080 2.5 0.2 - 5.5 8.9 20
High emissions 2060 - 2080 6.6 3.4 - 11 15 26 40
Low emissions 2080 – 2100 2.6 -0.2 - 6.4 11 25
High emissions 2080 – 2100 7.7 3.4 - 13 19 34 51
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 47 TABLE 4: Projected Sea-Level Rise (in feet) for North Spit Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.6 0.5 - 0.7 0.8 1 1.2
2040 0.9 0.7 - 1.1 1.2 1.6 2.0
2050 1.2 0.9 - 1.5 1.7 2.3 3.1
Low emissions 2060 1.3 1.0 - 1.7 2 2.8
High emissions 2060 1.5 1.2 - 1.9 2.2 3.1 4.3
Low emissions 2070 1.6 1.2 - 2 2.4 3.5
High emissions 2070 1.9 1.4 - 2.4 2.9 4 5.6
Low emissions 2080 1.8 1.4 - 2.4 2.9 4.4
High emissions 2080 2.3 1.7 - 2.9 3.5 5.1 7.2
Low emissions 2090 2.1 1.5 - 2.7 3.4 5.3
High emissions 2090 2.7 2.0 - 3.5 4.3 6.2 8.9
Low emissions 2100 2.3 1.7 - 3.1 3.9 6.3
High emissions 2100 3.1 2.3 - 4.1 5.1 7.6 10.9
Low emissions 2110* 2.5 1.9 - 3.3 4.2 7.1
High emissions 2110* 3.3 2.6 - 4.3 5.2 8 12.7
Low emissions 2120 2.7 2.0 - 3.7 4.8 8.2
High emissions 2120 3.7 2.9 - 4.9 6.1 9.4 15.0
Low emissions 2130 3 2.1 - 4 5.3 9.4
High emissions 2130 4.2 3.1 - 5.5 6.9 10.9 17.4
Low emissions 2140 3.2 2.3 - 4.4 5.9 10.7
High emissions 2140 4.6 3.4 - 6.2 7.8 12.5 20.1
Low emissions 2150 3.4 2.3 - 4.8 6.6 12.1
High emissions 2150 5 3.7 - 6.8 8.7 14.1 23.0

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 48 TABLE 5: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in North Spit
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

NORTH SPIT - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030 0.5%
2040 27.2% 0.1%
2050 76% 1.4% 0.1%
2060 94% 12% 0.6% 0.1%
2070 98% 40% 3.4% 0.5% 0.1% 0.1%
2080 99% 68% 14% 2.1% 0.5% 0.2% 0.1%
2090 100% 83% 33% 7% 1.8% 0.6% 0.3% 0.1% 0.1%
2100 100% 90% 54% 19% 6% 2% 0.8% 0.4% 0.2% 0.1%
2150 100% 100% 94% 76% 50% 28% 15% 8% 4% 3%
NORTH SPIT - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 86% 5.2% 0.3%
2070 94% 18% 1.4% 0.3%
2080 97% 37% 4% 0.8% 0.3% 0.1%
2090 98% 55% 10% 2.0% 0.7% 0.3% 0.2% 0.1% 0.1%
2100 98% 68% 20% 4% 1.5% 0.6% 0.3% 0.2% 0.1%
2150 100% 91% 63% 32% 15% 7% 4% 2% 2% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 49

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 6: Projected Average Rate of Sea-Level Rise (mm/year) for North Spit
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
High emissions 2030 – 2050 8.7 6.4 - 11 14 19 28
Low emissions 2060 - 2080 7.4 5.1 - 10 14 24
High emissions 2060 - 2080 11 8.2 - 16 20 31 44
Low emissions 2080 – 2100 7.4 4.5 - 11 16 29
High emissions 2080 – 2100 13 8.1 - 18 24 39 56
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 50 TABLE 7: Projected Sea-Level Rise (in feet) for Arena Cove Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.3 0.2 - 0.5 0.5 0.7 1.0
2040 0.5 0.3 - 0.7 0.9 1.2 1.6
2050 0.7 0.5 - 1.0 1.2 1.8 2.6
Low emissions 2060 0.8 0.5 - 1.1 1.4 2.2
High emissions 2060 1.0 0.6 - 1.3 1.7 2.5 3.7
Low emissions 2070 0.9 0.5 - 1.3 1.8 2.9
High emissions 2070 1.2 0.8 - 1.7 2.2 3.3 5.0
Low emissions 2080 1.0 0.6 - 1.6 2.1 3.6
High emissions 2080 1.5 1.0 - 2.2 2.8 4.3 6.4
Low emissions 2090 1.2 0.7 - 1.8 2.5 4.5
High emissions 2090 1.8 1.1 - 2.6 3.4 5.4 8.0
Low emissions 2100 1.3 0.7 - 2.1 3.0 5.4
High emissions 2100 2.1 1.3 - 3.1 4.1 6.7 9.9
Low emissions 2110* 1.4 0.8 - 2.2 3.1 6.0
High emissions 2110* 2.3 1.5 - 3.2 4.2 7.0 11.6
Low emissions 2120 1.5 0.9 - 2.5 3.6 7.1
High emissions 2120 2.6 1.8 - 3.8 5.0 8.2 13.9
Low emissions 2130 1.7 0.9 - 2.8 4.1 8.1
High emissions 2130 2.9 1.9 - 4.3 5.7 9.7 16.2
Low emissions 2140 1.8 0.9 - 3.1 4.6 9.4
High emissions 2140 3.2 2.1 - 4.8 6.5 11.1 18.7
Low emissions 2150 1.9 0.9 - 3.4 5.1 10.7
High emissions 2150 3.6 2.3 - 5.4 7.3 12.6 21.5

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 51 TABLE 8: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in Arena Cove
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

ARENA COVE - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030
2040 1.5%
2050 17% 0.3%
2060 44% 2% 0.2%
2070 68% 8% 0.8% 0.2% 0.1%
2080 82% 22% 3% 0.7% 0.2% 0.1% 0.1%
2090 89% 40% 9% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2100 91% 56% 20% 6% 2% 1% 0.4% 0.2% 0.1% 0.1%
2150 99% 89% 66% 40% 22% 12% 6% 4% 2% 1%
ARENA COVE - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 25% 0.9% 0.1%
2070 42% 3% 0.4% 0.1%
2080 55% 7% 1% 0.3% 0.2% 0.1%
2090 63% 13% 3% 0.8% 0.3% 0.2% 0.1% 0.1%
2100 69% 20% 5% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2150 81% 48% 22% 11% 5% 3% 2% 1% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 52

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 9: Projected Average Rate of Sea-Level Rise (mm/year) for Arena Cove
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
High emissions 2030 – 2050 5.8 3.5 - 8.4 11 17 25
Low emissions 2060 - 2080 4.4 2.1 - 7.4 11 22
High emissions 2060 - 2080 8.6 5.4 - 13 17 28 42
Low emissions 2080 – 2100 4.4 1.4 - 8.4 13 27
High emissions 2080 – 2100 9.6 5.0 - 15 21 36 54
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 53 TABLE 10: Projected Sea-Level Rise (in feet) for Point Reyes Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.4 0.3 - 0.6 0.6 0.8 1
2040 0.6 0.5 - 0.8 1.0 1.3 1.8
2050 0.9 0.6 - 1.1 1.4 2.0 2.8
Low emissions 2060 1.0 0.7 - 1.3 1.6 2.4
High emissions 2060 1.1 0.8 - 1.5 1.9 2.7 3.9
Low emissions 2070 1.1 0.8 - 1.6 2.0 3.1
High emissions 2070 1.4 1.0 - 1.9 2.4 3.5 5.2
Low emissions 2080 1.3 0.9 - 1.8 2.4 3.9
High emissions 2080 1.8 1.2 - 2.4 3.0 4.6 6.7
Low emissions 2090 1.5 1.0 - 2.1 2.8 4.8
High emissions 2090 2.1 1.4 - 2.9 3.7 5.6 8.3
Low emissions 2100 1.7 1.0 - 2.5 3.3 5.7
High emissions 2100 2.5 1.6 - 3.5 4.5 7.0 10.3
Low emissions 2110* 1.8 1.2 - 2.6 3.5 6.4
High emissions 2110* 2.6 1.9 - 3.6 4.6 7.3 12.0
Low emissions 2120 1.9 1.2 - 2.9 4.0 7.5
High emissions 2120 3.0 2.2 - 4.2 5.3 8.6 14.3
Low emissions 2130 2.1 1.3 - 3.2 4.5 8.6
High emissions 2130 3.4 2.4 - 4.7 6.1 10.1 16.6
Low emissions 2140 2.3 1.3 - 3.5 5.0 9.8
High emissions 2140 3.7 2.6 - 5.3 6.9 11.5 19.2
Low emissions 2150 2.4 1.3 - 3.8 5.6 11.2
High emissions 2150 4.1 2.8 - 5.9 7.8 13.1 22.0

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 54 TABLE 11: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in Point Reyes
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

POINT REYES - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030 0.1%
2040 4.0%
2050 34% 0.4%
2060 66% 3% 0.3% 0.1%
2070 84% 15% 1.3% 0.3% 0.1%
2080 93% 36% 5% 1.0% 0.3% 0.1% 0.1%
2090 96% 56% 15% 3% 0.9% 0.3% 0.2% 0.1% 0.1%
2100 96% 70% 30% 9% 3% 1% 0.5% 0.3% 0.2% 0.1%
2150 100% 96% 79% 53% 30% 16% 8% 5% 3% 2%
POINT REYES - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 45% 1.5% 0.2%
2070 64% 5% 0.6% 0.2%
2080 75% 12% 2% 0.4% 0.2% 0.1%
2090 81% 21% 4% 1.1% 0.4% 0.2% 0.1% 0.1%
2100 84% 33% 8% 2% 0.9% 0.4% 0.2% 0.1% 0.1%
2150 93% 63% 32% 15% 7% 4% 2% 2% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 55 High emissions 2030 – 2050 6.8 4.5 - 9.4 12 18 26
Low emissions 2060 - 2080 5.4 3.1 - 8.4 12 23
High emissions 2060 - 2080 9.6 6.4 - 14 18 29 43
Low emissions 2080 – 2100 5.3 2.4 - 9.3 14 28
High emissions 2080 – 2100 11 6.0 - 16 22 38 55

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 12: Projected Average Rate of Sea-Level Rise (mm/year) for Point Reyes
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

Probabilistic Projections (mm/yr) (based on Kopp et al. 2014) H++ scenario
(Sweet et al.
2017)
*Single
scenario
MEDIAN LIKELY RANGE 1-IN-20 CHANCE 1-IN-200 CHANCE
50% probability
sea-level rise meets
or exceeds…
66% probability
sea-level rise
is between…
5% probability
sea-level rise meets
or exceeds…

0.5% probability
sea-level rise meets
or exceeds…
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GA UGES | 56 TABLE 13: Projected Sea-Level Rise (in feet) for San Francisco Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 57 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030 0.1%
2040 3.3%
2050 31% 0.4%
2060 65% 3% 0.2% 0.1%
2070 84% 13% 1.2% 0.2% 0.1%
2080 93% 34% 5% 0.9% 0.3% 0.1% 0.1%
2090 96% 55% 14% 3% 0.9% 0.3% 0.2% 0.1% 0.1%
2100 96% 70% 28% 8% 3% 1% 0.5% 0.3% 0.2% 0.1%
2150 100% 96% 79% 52% 28% 15% 8% 4% 3% 2%
1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 43% 1.4% 0.2%
2070 62% 4% 0.6% 0.2%
2080 74% 11% 2% 0.4% 0.2% 0.1%
2090 80% 20% 3% 1.0% 0.4% 0.2% 0.1% 0.1%
2100 84% 31% 7% 2% 0.8% 0.4% 0.2% 0.1% 0.1%
2150 93% 62% 31% 14% 7% 4% 2% 2% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 14: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in San Francisco
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

SAN FRANCISCO - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) SAN FRANCISCO - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GA UGES | 58 TABLE 15: Projected Average Rate of Sea-Level Rise (mm/year) for San Francisco
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
High emissions
Low emissions
2030 – 2050 6.7 4.5 - 9.3 12 17 26
2060 - 2080 5.3 3.1 - 8.2 12 22
High emissions
Low emissions
2060 - 2080 9.5 6.4 - 13 17 28 42
2080 – 2100 5.2 2.3 - 9.1 14 28
High emissions 2080 – 2100 11 6.0 - 16 22 37 55

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 59 TABLE 16: Projected Sea-Level Rise (in feet) for Monterey Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.4 0.3 - 0.5 0.6 0.8 1.0
2040 0.6 0.4 - 0.8 0.9 1.2 1.7
2050 0.8 0.5 - 1.1 1.3 1.9 2.7
Low emissions 2060 0.9 0.5 - 1.2 1.5 2.3
High emissions 2060 1.0 0.7 - 1.4 1.8 2.6 3.8
Low emissions 2070 1.0 0.6 - 1.4 1.9 3.0
High emissions 2070 1.3 0.9 - 1.8 2.3 3.4 5.1
Low emissions 2080 1.2 0.7 - 1.7 2.3 3.8
High emissions 2080 1.6 1.1 - 2.3 2.9 4.4 6.6
Low emissions 2090 1.3 0.8 - 2.0 2.7 4.6
High emissions 2090 2.0 1.3 - 2.8 3.5 5.5 8.2
Low emissions 2100 1.5 0.9 - 2.3 3.1 5.5
High emissions 2100 2.3 1.5 - 3.3 4.3 6.9 10.1
Low emissions 2110* 1.6 1.0 - 2.4 3.3 6.1
High emissions 2110* 2.5 1.7 - 3.4 4.4 7.2 11.8
Low emissions 2120 1.7 1.0 - 2.7 3.8 7.3
High emissions 2120 2.8 2.0 - 4.0 5.2 8.5 14.0
Low emissions 2130 1.9 1.1 - 3.0 4.2 8.3
High emissions 2130 3.1 2.2 - 4.5 5.9 9.9 16.4
Low emissions 2140 2.0 1.1 - 3.2 4.7 9.5
High emissions 2140 3.5 2.4 - 5.1 6.7 11.3 18.9
Low emissions 2150 2.1 1.1 - 3.6 5.3 10.8
High emissions 2150 3.8 2.6 - 5.7 7.6 12.9 21.8

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 60 TABLE 17: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in Monterey
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

MONTEREY - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030 0.1%
2040 2.5%
2050 24% 0.3%
2060 55% 2% 0.2% 0.1%
2070 77% 11% 1.1% 0.2% 0.1%
2080 88% 29% 4% 0.8% 0.3% 0.1% 0.1%
2090 93% 48% 12% 3% 0.8% 0.3% 0.2% 0.1% 0.1%
2100 94% 63% 25% 7% 2% 1% 0.4% 0.2% 0.1% 0.1%
2150 100% 93% 73% 46% 25% 14% 7% 4% 2% 2%
MONTEREY - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 34% 1.2% 0.1%
2070 52% 4% 0.5% 0.1%
2080 64% 9% 1% 0.4% 0.2% 0.1%
2090 72% 16% 3% 0.9% 0.3% 0.2% 0.1% 0.1%
2100 77% 25% 6% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2150 87% 55% 26% 12% 6% 4% 2% 1% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 61

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 18: Projected Average Rate of Sea-Level Rise (mm/year) for Monterey
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
High emissions 2030 – 2050 6.3 4.0 - 9.0 11 17 25
Low emissions 2060 - 2080 4.9 2.6 - 7.8 11 22
High emissions 2060 - 2080 9.1 5.9 - 13 17 28 43
Low emissions 2080 – 2100 4.7 1.8 - 8.7 13 27
High emissions 2080 – 2100 10 5.5 - 16 22 37 54
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 62 TABLE 19: Projected Sea-Level Rise (in feet) for Port San Luis Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.3 0.2 - 0.5 0.5 0.7 1.0
2040 0.5 0.3 - 0.7 0.8 1.2 1.6
2050 0.7 0.5 - 1.0 1.2 1.8 2.6
Low emissions 2060 0.8 0.4 - 1.1 1.4 2.2
High emissions 2060 1.0 0.6 - 1.3 1.7 2.5 3.7
Low emissions 2070 0.9 0.5 - 1.3 1.7 2.9
High emissions 2070 1.2 0.8 - 1.7 2.2 3.3 5.0
Low emissions 2080 1.0 0.6 - 1.6 2.1 3.6
High emissions 2080 1.5 1.0 - 2.1 2.8 4.3 6.4
Low emissions 2090 1.1 0.6 - 1.8 2.5 4.5
High emissions 2090 1.8 1.1 - 2.6 3.4 5.3 8.0
Low emissions 2100 1.3 0.7 - 2.1 2.9 5.4
High emissions 2100 2.1 1.3 - 3.1 4.1 6.7 9.9
Low emissions 2110* 1.4 0.8 - 2.2 3.1 5.9
High emissions 2110* 2.3 1.5 - 3.2 4.2 7.0 11.6
Low emissions 2120 1.5 0.8 - 2.4 3.5 7.0
High emissions 2120 2.6 1.8 - 3.7 4.9 8.2 13.8
Low emissions 2130 1.6 0.9 - 2.7 4.0 8.0
High emissions 2130 2.9 2.0 - 4.3 5.7 9.6 16.2
Low emissions 2140 1.7 0.9 - 3.0 4.5 9.2
High emissions 2140 3.2 2.1 - 4.8 6.4 11.1 18.7
Low emissions 2150 1.9 0.8 - 3.3 5.1 10.5
High emissions 2150 3.6 2.3 - 5.4 7.3 12.6 21.5

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 63 TABLE 20: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in Port San Luis
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

PORT SAN LUIS - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030
2040 1.5%
2050 16% 0.3%
2060 44% 2% 0.2% 0.1%
2070 68% 8% 0.8% 0.2% 0.1%
2080 82% 22% 3% 0.7% 0.2% 0.1% 0.1%
2090 89% 40% 9% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2100 91% 56% 20% 6% 2% 1% 0.4% 0.2% 0.1% 0.1%
2150 99% 89% 66% 40% 21% 11% 6% 4% 2% 1%
PORT SAN LUIS - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 24% 0.9% 0.1%
2070 40% 3% 0.4% 0.1%
2080 52% 6% 1% 0.3% 0.2% 0.1%
2090 61% 12% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2100 67% 19% 4% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2150 80% 46% 21% 10% 5% 3% 2% 1% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 64

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 21: Projected Average Rate of Sea-Level Rise (mm/year) for Port San Luis
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
High emissions 2030 – 2050 5.8 3.5 - 8.4 11 17 24
Low emissions 2060 - 2080 4.3 2.1 - 7.2 11 21
High emissions 2060 - 2080 8.5 5.4 - 13 17 27 42
Low emissions 2080 – 2100 4.1 1.2 - 8.0 13 27
High emissions 2080 – 2100 9.6 5.0 - 15 21 37 54
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 65 TABLE 22: Projected Sea-Level Rise (in feet) for Santa Barbara Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.3 0.2 - 0.4 0.5 0.7 1.0
2040 0.5 0.3 - 0.7 0.8 1.1 1.6
2050 0.7 0.4 - 1.0 1.2 1.8 2.5
Low emissions 2060 0.7 0.4 - 1.0 1.4 2.2
High emissions 2060 0.9 0.6 - 1.3 1.6 2.5 3.6
Low emissions 2070 0.9 0.5 - 1.3 1.7 2.8
High emissions 2070 1.1 0.7 - 1.7 2.1 3.3 4.9
Low emissions 2080 1.0 0.5 - 1.5 2.0 3.6
High emissions 2080 1.4 0.9 - 2.1 2.7 4.3 6.3
Low emissions 2090 1.1 0.6 - 1.8 2.4 4.4
High emissions 2090 1.7 1.1 - 2.6 3.3 5.3 7.9
Low emissions 2100 1.2 0.6 - 2.0 2.9 5.3
High emissions 2100 2.1 1.2 - 3.1 4.1 6.6 9.8
Low emissions 2110* 1.3 0.7 - 2.1 3.0 5.9
High emissions 2110* 2.2 1.4 - 3.2 4.2 6.9 11.5
Low emissions 2120 1.4 0.7 - 2.4 3.5 7.0
High emissions 2120 2.5 1.7 - 3.7 4.9 8.2 13.7
Low emissions 2130 1.5 0.8 - 2.6 3.9 8.0
High emissions 2130 2.9 1.8 - 4.2 5.6 9.5 16.0
Low emissions 2140 1.6 0.8 - 2.9 4.4 9.1
High emissions 2140 3.1 2.0 - 4.8 6.4 11.0 18.6
Low emissions 2150 1.8 0.7 - 3.2 5.0 10.5
High emissions 2150 3.5 2.2 - 5.3 7.2 12.6 21.4

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 66 TABLE 23: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in Santa Barbara
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

SANTA BARBARA - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030
2040 1.3%
2050 14% 0.2%
2060 40% 2% 0.2%
2070 64% 7% 0.8% 0.2% 0.1%
2080 78% 20% 3% 0.7% 0.2% 0.1% 0.1%
2090 86% 37% 8% 2% 0.7% 0.3% 0.1% 0.1% 0.1%
2100 89% 53% 19% 6% 2% 1% 0.3% 0.2% 0.1% 0.1%
2150 98% 87% 63% 38% 20% 11% 6% 3% 2% 1%
SANTA BARBARA - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 21% 0.8% 0.1%
2070 35% 2% 0.3% 0.1%
2080 48% 6% 1% 0.3% 0.1% 0.1%
2090 57% 11% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2100 63% 17% 4% 1% 0.6% 0.3% 0.2% 0.1% 0.1%
2150 76% 42% 19% 9% 5% 3% 2% 1% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 67 TABLE 24: Projected Average Rate of Sea-Level Rise (mm/year) for Santa Barbara
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
High emissions 2030 – 2050 5.6 3.3 - 8.2 11 16 24
Low emissions 2060 - 2080 4.1 1.9 - 7.0 10 21
High emissions 2060 - 2080 8.3 5.1 - 12 16 27 41
Low emissions 2080 – 2100 3.9 0.91 - 7.8 12 27
High emissions 2080 – 2100 9.4 4.8 - 15 21 36 53

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 68 TABLE 25: Projected Sea-Level Rise (in feet) for Santa Monica Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.4 0.3 - 0.5 0.6 0.8 1
2040 0.6 0.4 - 0.8 0.9 1.2 1.7
2050 0.8 0.6 - 1.1 1.3 1.9 2.6
Low emissions 2060 0.9 0.6 - 1.2 1.5 2.3
High emissions 2060 1.1 0.8 - 1.4 1.8 2.6 3.8
Low emissions 2070 1.0 0.7 - 1.4 1.9 3.0
High emissions 2070 1.3 1.0 - 1.8 2.3 3.4 5.1
Low emissions 2080 1.2 0.8 - 1.7 2.3 3.8
High emissions 2080 1.7 1.1 - 2.3 2.9 4.4 6.5
Low emissions 2090 1.3 0.8 - 2.0 2.7 4.6
High emissions 2090 2.0 1.3 - 2.8 3.5 5.5 8.1
Low emissions 2100 1.5 0.9 - 2.3 3.1 5.5
High emissions 2100 2.3 1.5 - 3.3 4.3 6.8 10.0
Low emissions 2110* 1.6 1.0 - 2.4 3.3 6.1
High emissions 2110* 2.5 1.8 - 3.5 4.5 7.2 11.7
Low emissions 2120 1.7 1.0 - 2.7 3.8 7.3
High emissions 2120 2.9 2.0 - 4.0 5.2 8.5 14.0
Low emissions 2130 1.9 1.1 - 3.0 4.2 8.3
High emissions 2130 3.2 2.2 - 4.5 5.9 9.8 16.3
Low emissions 2140 2.0 1.1 - 3.2 4.7 9.4
High emissions 2140 3.5 2.4 - 5.1 6.7 11.3 18.9
Low emissions 2150 2.2 1.1 - 3.6 5.3 10.8
High emissions 2150 3.9 2.6 - 5.7 7.6 12.9 21.7

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 69 TABLE 26: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in Santa Monica
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

SANTA MONICA - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030 0.1%
2040 2.5%
2050 25% 0.3%
2060 58% 2% 0.2% 0.1%
2070 79% 11% 1.0% 0.2% 0.1%
2080 89% 30% 4% 0.8% 0.3% 0.1% 0.1%
2090 94% 50% 12% 3% 0.8% 0.3% 0.2% 0.1% 0.1%
2100 95% 65% 25% 7% 2% 1% 0.4% 0.2% 0.1% 0.1%
2150 100% 94% 74% 47% 26% 14% 7% 4% 2% 2%
SANTA MONICA - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 35% 1.2% 0.1%
2070 53% 4% 0.5% 0.1%
2080 66% 9% 1% 0.4% 0.2% 0.1%
2090 74% 16% 3% 0.9% 0.3% 0.2% 0.1% 0.1%
2100 78% 25% 6% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2150 89% 56% 26% 12% 6% 4% 2% 1% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 70 TABLE 27: Projected Average Rate of Sea-Level Rise (mm/year) for Santa Monica
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
High emissions 2030 – 2050 6.4 4.3 - 8.9 11 17 24
Low emissions 2060 - 2080 4.9 2.8 - 7.8 11 22
High emissions 2060 - 2080 9.2 6.0 - 13 17 28 42
Low emissions 2080 – 2100 4.6 1.6 - 8.5 13 27
High emissions 2080 – 2100 10 5.6 - 16 22 37 54

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 71 TABLE 28: Projected Sea-Level Rise (in feet) for Los Angeles Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.3 0.2 - 0.5 0.6 0.7 1.0
2040 0.5 0.4 - 0.7 0.9 1.2 1.7
2050 0.7 0.5 - 1.0 1.2 1.8 2.6
Low emissions 2060 0.8 0.5 - 1.1 1.4 2.2
High emissions 2060 1.0 0.7 - 1.3 1.7 2.5 3.7
Low emissions 2070 0.9 0.6 - 1.3 1.8 2.9
High emissions 2070 1.2 0.8 - 1.7 2.2 3.3 5.0
Low emissions 2080 1.0 0.6 - 1.6 2.1 3.6
High emissions 2080 1.5 1.0 - 2.2 2.8 4.3 6.4
Low emissions 2090 1.2 0.7 - 1.8 2.5 4.5
High emissions 2090 1.8 1.2 - 2.7 3.4 5.3 8.0
Low emissions 2100 1.3 0.7 - 2.1 3.0 5.4
High emissions 2100 2.2 1.3 - 3.2 4.1 6.7 9.9
Low emissions 2110* 1.4 0.9 - 2.2 3.1 6.0
High emissions 2110* 2.3 1.6 - 3.3 4.3 7.1 11.5
Low emissions 2120 1.5 0.9 - 2.5 3.6 7.1
High emissions 2120 2.7 1.8 - 3.8 5.0 8.3 13.8
Low emissions 2130 1.7 0.9 - 2.8 4.0 8.1
High emissions 2130 3.0 2.0 - 4.3 5.7 9.7 16.1
Low emissions 2140 1.8 0.9 - 3.0 4.5 9.2
High emissions 2140 3.3 2.2 - 4.9 6.5 11.1 18.7
Low emissions 2150 1.9 0.9 - 3.3 5.1 10.6
High emissions 2150 3.7 2.4 - 5.4 7.3 12.7 21.5

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 72 TABLE 29: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in Los Angeles
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

LOS ANGELES - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030
2040 1.6%
2050 17% 0.3%
2060 47% 2% 0.2%
2070 71% 8% 0.8% 0.2% 0.1%
2080 84% 23% 3% 0.7% 0.2% 0.1% 0.1%
2090 90% 42% 9% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2100 92% 58% 21% 6% 2% 1% 0.4% 0.2% 0.1% 0.1%
2150 99% 90% 68% 42% 23% 12% 6% 4% 2% 1%
LOS ANGELES - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 25% 0.9% 0.1%
2070 42% 3% 0.4% 0.1%
2080 55% 7% 1% 0.3% 0.2% 0.1%
2090 64% 13% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2100 69% 20% 5% 2% 0.7% 0.3% 0.2% 0.1% 0.1%
2150 82% 48% 22% 10% 5% 3% 2% 1% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 73

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 30: Projected Average Rate of Sea-Level Rise (mm/year) for Los Angeles
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et
al. 2017)
*Single
scenario
High emissions 2030 – 2050 5.9 3.8 - 8.4 11 16 25
Low emissions 2060 - 2080 4.5 2.3 - 7.3 11 21
High emissions 2060 - 2080 8.7 5.5 - 13 17 27 42
Low emissions 2080 – 2100 4.1 1.1 - 8.0 13 27
High emissions 2080 – 2100 9.7 5.1 - 15 21 37 54
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 74 TABLE 31: Projected Sea-Level Rise (in feet) for La Jolla Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.5 0.4 - 0.6 0.7 0.9 1.1
2040 0.7 0.5 - 0.9 1.0 1.3 1.8
Low emissions
2050 0.9 0.7 - 1.2 1.4 2.0 2.8
2060 1.0 0.7 - 1.3 1.7 2.5
High emissions
Low emissions
2060 1.2 0.9 - 1.6 1.9 2.7 3.9
2070 1.2 0.9 - 1.6 2.0 3.1
High emissions
Low emissions
2070 1.5 1.1 - 2.0 2.5 3.6 5.2
2080 1.4 1.0 - 1.9 2.4 4.0
High emissions
Low emissions
2080 1.9 1.3 - 2.5 3.1 4.6 6.7
2090 1.6 1.0 - 2.2 2.9 4.8
High emissions
Low emissions
2090 2.2 1.6 - 3.0 3.8 5.7 8.3
2100 1.7 1.1 - 2.5 3.3 5.8
High emissions
Low emissions
2100 2.6 1.8 - 3.6 4.6 7.1 10.2
2110* 1.9 1.3 - 2.7 3.5 6.4
High emissions
Low emissions
2110* 2.8 2.0 - 3.7 4.7 7.5 12.0
2120 2.0 1.3 - 3.0 4.1 7.6
High emissions
Low emissions
2120 3.1 2.3 - 4.3 5.5 8.8 14.3
2130 2.2 1.4 - 3.2 4.5 8.6
High emissions
Low emissions
2130 3.5 2.5 - 4.9 6.3 10.2 16.6
2140 2.4 1.5 - 3.6 5.1 9.7
High emissions
Low emissions
2140 3.9 2.8 - 5.4 7.1 11.7 19.2
2150 2.5 1.5 - 3.9 5.7 11.1
High emissions 2150 4.3 3.0 - 6.1 7.9 13.3 22.0

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 75 TABLE 32: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in La Jolla
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050; the H++ scenario is not included in this table.

LA JOLLA - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030 0.1%
2040 5.5%
2050 40% 0.5%
2060 74% 4% 0.3% 0.1%
2070 89% 17% 1.5% 0.3% 0.1%
2080 95% 41% 6% 1.1% 0.3% 0.1% 0.1%
2090 97% 62% 17% 4% 1.0% 0.4% 0.2% 0.1% 0.1%
2100 98% 75% 33% 10% 3% 1% 0.5% 0.3% 0.2% 0.1%
2150 100% 97% 83% 58% 33% 17% 9% 5% 3% 2%
LA JOLLA - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 52% 1.7% 0.2%
2070 70% 6% 0.7% 0.2%
2080 80% 14% 2% 0.4% 0.2% 0.1%
2090 85% 24% 4% 1.1% 0.4% 0.2% 0.1% 0.1%
2100 88% 36% 8% 2% 0.9% 0.4% 0.2% 0.1% 0.1%
2150 96% 68% 35% 16% 8% 4% 3% 2% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 76 MEDIAN LIKELY RANGE 1-IN-20 CHANCE 1-IN-200 CHANCE
50% probability
sea-level rise meets
or exceeds…
66% probability
sea-level rise
is between…
5% probability
sea-level rise meets
or exceeds…

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et
al. 2017)
*Single
scenario
High emissions 2030 – 2050 7.2 5.1 - 9.6 12 18 26
Low emissions 2060 - 2080 5.7 3.5 - 8.6 12 22
High emissions 2060 - 2080 9.9 6.7 - 14 18 29 43
Low emissions 2080 – 2100 5.3 3.4 - 9.2 14 28
High emissions 2080 – 2100 11 6.5 - 17 22 38 54

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 33: Projected Average Rate of Sea-Level Rise (mm/year) for Los Jolla
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column). Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

Probabilistic Projections (mm/yr) (based on Kopp et al. 2014) APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 77 TABLE 34: Projected Sea-Level Rise (in feet) for San Diego Probabilistic projections for the height of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column), as seen in the Rising Seas Report. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. Recommended projections for use in low, medium-high and extreme risk aversion decisions are outlined in blue boxes below.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et al.
2017)
*Single
scenario
Low
Risk
Aversion
Medium - High
Risk Aversion
Extreme
Risk Aversion
High emissions 2030 0.4 - 0.6 0.7 0.9 1.1
2040 0.7 0.5 - 0.9 1.0 1.3 1.8
2050 0.9 0.7 - 1.2 1.4 2.0 2.8
Low emissions 2060 1.0 0.7 - 1.3 1.7 2.5
High emissions 2060 1.2 0.9 - 1.6 1.9 2.7 3.9
Low emissions 2070 1.2 0.9 - 1.6 2.0 3.1
High emissions 2070 1.5 1.1 - 2.0 2.5 3.6 5.2
Low emissions 2080 1.4 1.0 - 1.9 2.4 3.9
High emissions 2080 1.9 1.3 - 2.5 3.1 4.6 6.7
Low emissions 2090 1.6 1.0 - 2.2 2.9 4.8
High emissions 2090 2.2 1.6 - 3.0 3.7 5.7 8.3
Low emissions 2100 1.7 1.1 - 2.5 3.3 5.8
High emissions 2100 2.6 1.8 - 3.6 4.5 7.0 10.2
Low emissions 2110* 1.9 1.3 - 2.7 3.5 6.4
High emissions 2110* 2.8 2.0 - 3.7 4.7 7.5 12.0
Low emissions 2120 2.0 1.3 - 3.0 4.1 7.6
High emissions 2120 3.1 2.3 - 4.3 5.5 8.8 14.3
Low emissions 2130 2.2 1.4 - 3.3 4.6 8.6
High emissions 2130 3.5 2.6 - 4.9 6.3 10.2 16.6
Low emissions 2140 2.4 1.5 - 3.6 5.1 9.8
High emissions 2140 3.9 2.8 - 5.4 7.1 11.7 19.2
Low emissions 2150 2.5 1.5 - 3.9 5.7 11.1
High emissions 2150 4.3 3.0 - 6.1 7.9 13.3 22.0

APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 78 TABLE 35: Probability that Sea-Level Rise will meet or exceed a particular height (in feet) in San Diego
Estimated probabilities that sea-level rise will meet or exceed a particular height are based on Kopp et al. 2014. All heights are with respect to a 1991 – 2009 baseline; values refer to a 19-year average centered on the specified year. Areas shaded in grey have less than a 0.1% probability of occurrence. Values below are based on probabilistic projections; for low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050;. the H++ scenario is not included in this table.

SAN DIEGO - High emissions (RCP 8.5)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2030 0.1%
2040 5.4%
2050 40% 0.5%
2060 74% 4% 0.3% 0.1%
2070 89% 17% 1.5% 0.3% 0.1%
2080 95% 41% 6% 1.1% 0.3% 0.1% 0.1%
2090 97% 62% 17% 3% 1.0% 0.4% 0.2% 0.1% 0.1%
2100 98% 76% 33% 10% 3% 1% 0.5% 0.3% 0.2% 0.1%
2150 100% 97% 83% 58% 33% 17% 9% 5% 3% 2%
SAN DIEGO - Low emissions (RCP 2.6)
Probability that sea-level rise will meet or exceed… (excludes H++) 1 FT. 2 FT. 3 FT. 4 FT. 5 FT. 6 FT. 7 FT. 8 FT. 9 FT. 10 FT. 2060 52% 1.7% 0.2%
2070 70% 5% 0.6% 0.2%
2080 80% 14% 2% 0.4% 0.2% 0.1%
2090 86% 24% 4% 1.1% 0.4% 0.2% 0.1% 0.1%
2100 88% 36% 8% 2% 0.9% 0.4% 0.2% 0.1% 0.1%
2150 96% 68% 35% 16% 8% 4% 3% 2% 1% 1%

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 79

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
TABLE 36: Projected Average Rate of Sea-Level Rise (mm/year) for San Diego
Probabilistic projections for the rates of sea-level rise shown below, along with the H++ scenario (depicted in blue in the far right column.) Values are presented in this table as mm/yr, as opposed to feet as in the previous two tables, to avoid reporting values in fractions of an inch. The H++ projection is a single scenario and does not have an associated likelihood of occurrence as do the probabilistic projections. Probabilistic projections are with respect to a baseline of the year 2000, or more specifically the average relative sea level over 1991 - 2009. High emissions represents RCP 8.5; low emissions represents RCP 2.6. For low emissions (RCP 2.6) the starting year is 2060 as we are currently on a high emissions (RCP 8.5) trajectory through 2050.

0.5% probability
sea-level rise meets
or exceeds…
H++ scenario
(Sweet et
al. 2017)
*Single
scenario
High emissions 2030 – 2050 7.2 5.1 - 9.6 12 17 26
Low emissions 2060 - 2080 5.7 3.5 - 8.6 12 22
High emissions 2060 - 2080 9.9 6.7 - 14 18 29 43
Low emissions 2080 – 2100 5.4 2.4 - 9.2 14 28
High emissions 2080 – 2100 11 6.5 - 17 22 38 54
APPENDIX 3: SEA-LEVEL RISE PROJECTIONS FOR ALL 12 TIDE GAUGES | 80

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 4:

Risk Decision Framework

(Adapted from the Governor’s Office of Planning and Research’s

“Planning and Investing for a Resilient California: A Guidebook for State Agencies”)

This framework serves to help planners and decision makers evaluate sea-level rise impacts

across a range of projections to inform appropriate design, adaptation pathways,

and contingency plans that build resilience.

RISK

CONSIDERATIONS
& EVALUATION
Consequences
of Impact
or Disruption
LOW
Minimum Disruption,
Limited Scale
and Scope

MEDIUM TO HIGH
Inconvenience,
but Limited
in Scope and Scale

EXTREME
Unacceptable Risk
and/or Extensive Scale
and Scope
Adaptive
Capacity
• Future flexibility
maintained
• People or systems
readily able to respond
or adapt
• Limited future flexibility • Irreversible
• Threat to public health
and safety
Who or What
is Affected?
• Low impact on
communities,
infrastructure, or
natural systems
• Communities,
systems, or infrastructure
readily able to adapt or
respond to change
• Vulnerable populations
• Critical infrastructure
• Critical natural systems
• Areas of economic,
historic, or cultural
significance
Economic
Impacts LOW MEDIUM HIGH

EMISSIONS SCENARIO

EVALUATION
Pre-2050 RCP 8.5
(high emissions)
RCP 8.5
(high emissions)
RCP 8.5
(high emissions)
Post-2050 EVALUATE RCP 2.6 AND RCP 8.5
(low emissions and high emissions)

SLR PROJECTIONS

SELECTION

LOW RISK

AVERSION

MEDIUM-HIGH

RISK AVERSION

EXTREME

RISK AVERSION
APPENDIX 4: RISK DECISION FRAMEWORK | 81

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
APPENDIX 5:

Questions from the Policy Advisory
Committee to the OPC-SAT Working Group
THE QUESTIONS BELOW were developed by the Policy Advisory Committee to the OPC-SAT Working Group to elicit information about the current estimates of sea-level rise for the California coast and how to understand the scientific context around those estimates, including the state of the science (e.g., areas of uncertainty, emerging science), the importance of each contributor to sea-level rise, and sensitivity of the estimates to policy actions. Sections noted in parentheses reference locations in the Rising Seas Report where these questions were addressed.

Estimates of Sea-level Rise

1. What is the current range of estimates of sea level rise for the California coast? (Section 3)
a. What probabilities can be assigned to those
estimates given the current state of science?
(Section 3.1)
b. Should more weight be given to certain
parts of the range, and if so, why?
(Section 3.2)

2. Across the physically plausible range of sealevel rise projections, is it possible to say which scenario(s) are more likely than others?
(Section 3.1.2)
a. What progress has been made since the
existing State Sea-level Rise Guidance
Document was published in 2013 on
assigning probabilities to different
emissions, warming and sea-level rise
scenarios? (Section 3.1.2)
b. Which contributors to sea-level rise (e.g.,
thermal expansion, ice loss) are currently
included in developing probabilistic sealevel rise scenarios? (Section 3.1.2) c. What is the OPC-SAT Working Group’s
recommendation on how to estimate the
likelihood of certain amounts of sea-level
rise occurring at future dates for a given
global emissions scenario? (Section 3.1.2)
d. What other approaches is the OPC-SAT
Working Group aware of, or could the
Working Group recommend, for presenting
uncertain sea-level rise projections?
(Section 3.1.2)
e. Is it possible to identify and characterize
the degree of uncertainty in different
contributors to sea-level rise? Where do the
biggest uncertainties lie and what causes
these uncertainties? (Box 3)
State of the Science
These questions are designed to elicit information on
the state of sea-level rise science, including emerging issues and the treatment of ice loss in Antarctica.

3. What are the significant and notable emerging
insights in sea-level rise science since the current
State Sea-Level Rise Policy Guidance was issued?
Why do they warrant attention? (Section 2.2)
a. Have there been any notable changes in
understanding how thermal expansion of
ocean water contributes to sea-level rise?
(Section 2.1.1 and Section 2.2)
b. Have there been any notable changes in
understanding of the role of ice loss from
inland glaciers and major ice sheets?
(Section 2.1 and 2.2)
APPENDIX 5: QUESTIONS FROM THE POLICY ADVISORY COMMITTEE TO THE OPC-SAT WORKING GROUP | 82

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
c. Have there been any notable changes in
understanding of steric or dynamic ocean
current changes that affect regional sealevel rise projections? (Section 3.1.2) d. Have there been any notable changes in
understanding of local or regional land
movement that could affect projections of
relative sea level change? (Section 2.2)

4. Does the OPC-SAT Working Group consider
the emerging science important and significant
enough to warrant consideration in the current
update to the State Sea-level Rise Guidance
Document? If yes, why? If no, why? Please
comment on the current confidence in new
scientific insights or advances. (Section 2.2,
Section 3.1.1, Appendix 2)

5. Existing models, including Kopp et al. (2014) and
Cayan et al. (2016), project very different sea-level
rise estimates under different emissions scenarios.

However, some scientists suggest that sea levels
in 2100 are determined by events in Antarctica,
regardless of future GHG emission levels and
trajectories. What is your scientific opinion about
this issue? (Section 2.1, Section 3.2)

6. What are the scientific advances in best
approaches to project sea-level rise since the
publication of the existing State Sea-level Rise
Guidance Document (2013)? What makes some
modeling approaches better than others; in what
way? (Section 3.1)
a. What are the strengths and weaknesses
of the different approaches for projecting
global sea-level rise? (Section 3.1)
b. Which approach or combination of
approaches would the OPC-SAT Working
Group recommend for estimating future
global sea levels? (Section 3.1.2)

7. What are the best/most reliable approaches
for translating global projections into regional
projections? (Section 3.1.2)

8. What are the factors that cause sea-level rise
projections to differ among locations?
(Section 2.1.2, Box 2)

9. How are these factors considered in regional
projections? (Section 3.1.2)

10. Is the OPC-SAT Working Group aware of
additional research/modeling efforts, etc.,
presently underway that should inform the
update to the State Sea-level Rise Guidance
Document? (Section 4.1)
a. How soon does the OPC-SAT Working
Group expect major breakthroughs in
understanding of sea-level changes? What
would constitute a major breakthrough?
How might these breakthroughs affect
sea-level rise projections? Given current
uncertainties in scientific understanding,
and the anticipated rate of accumulation
of new knowledge or observations, can the
Working Group provide a recommended
frequency for reviewing the latest available
science to update guidance for state and
local decision-makers?
(Section 1.4, Section 4.1, Appendix 2)
b. Similarly, can the Working Group provide
recommendations, from a scientific
perspective, on how this science could
be considered in a policy setting (e.g.,
establishing an appropriate frequency for
policy updates, establishing a scientific
body to provide regular updates)?
(Section 1.4)
Understanding the Contributors to Local
Sea-Level Rise

11. In addition to projecting future sea levels, other factors may also be important.
a. What is the state of science on identifying
future (a) tidal amplitude and/or phase,
and (b) frequency and intensity of extreme
events (e.g., high water due to storm surges,
ENSO events)? (Box 1)
APPENDIX 5: QUESTIONS FROM THE POLICY ADVISORY COMMITTEE TO THE OPC-SAT WORKING GROUP | 83

STATE OF CALIFORNIA SEA-LEVEL RISE GUIDANCE
b. What are the pros and cons of different
approaches of arriving at total water level?
(Box 4)
c. What is the OPC-SAT Working Group’s
recommendation on how to integrate
(global or regional) sea-level rise projections
with expected changes in tidal and extreme
events? (Box 4)
d. What is the OPC-SAT Working Group’s
assessment of the adequacy of
superimposing historical extreme event
departures from mean onto projected mean
sea levels to estimate future values? (Box 4)
Policy Sensitivity of Sea-Level Rise
Projections

12. How “policy dependent” are the different
contributors to sea-level rise? (Section 2.3)
a. Are the different contributors to sea-level
rise equally sensitive to changes in global
emissions/temperature? (Section 2.1)
b. How much sea-level rise can be avoided
or how much can it be slowed down by
significant emission reductions (e.g.,
achieving the global commitments made
at COP21 in Paris or 80% GHG emissions
reductions by 2050)?
(Section 2.1, Section 3.2, and Section 3.3)
c. What new implications for planning and
decision making, if any, are introduced by
including ice loss scenarios in sea-level rise
projections (e.g., magnitude, timing, nonlinear rates, nature of the impact)? (Section 3.1.2. Appendix 2)

13. Sea-level rise projections typically use emissions
scenarios (e.g., IPCC emissions scenarios/
Representative Concentration Pathways (RCPs)
as inputs into general circulation/sea-level rise
models. The RCP 2.6 scenario (lowest IPCC
emission scenario) appears out of reach, given
current greenhouse gas emission trends, and the
unlikely development of more ambitious emission
reduction targets in the near future. Is there any
physically plausible scenario under which it
remains sensible to retain such low-end scenarios
in the range of projections? If not, what is the
lowest plausible sea-level rise scenario?
(Section 3.1.1)
Sea-Level Rise Exposure vs. Risk-based
Assessment

14. Risk (often defined as probability multiplied by
consequence) is a critical input to planning and
decision-making.?
a. What is the OPC-SAT Working Group’s
recommendation on whether and, if so,
how to incorporate consideration of risk as
part of the State Sea-level Rise Guidance
Document to state and local decisionmakers? (Section 1.3, Section 4.2) b. How would this approach take account
of the uncertainties in sea-level rise
projections? (Section 4.2, Box 3)

15. What other questions should we be asking that
we haven’t asked? What other considerations
should be brought to bear on this topic?
Photo Credits
COVER: © Keith Willis
PG 7: © Kenneth & Gabrielle Adelman
PG 10: © Dave Revell
PG 11: © Aldaron Laird
PG 21: © Aldaron Laird
PG 22: © Claire Facker
PG 23: © Ron Rothbart
PG 28: © Dave R. (Flickr)
PG 34: © Gabe Buhr
APPENDIX 5: QUESTIONS FROM THE POLICY ADVISORY COMMITTEE TO THE OPC-SAT WORKING GROUP | 84 Mr. Christian Murdoch Page 31
February 28, 2022
ATTACHMENT 5: SITE ACCESS PHOTOGRAPHS
As shown in the Photos below, the Pedro Point Site has historically and consistently been a wetlands and coastal access point.

Modern Setting– Informal Foot Trails to the Shore and Drainage to San Pedro Creek Wetlands
Informal (trampled) foot trail network connections between public road (San Pedro Avenue) and public access to shoreline, across Pedro Point Field. April 2013.

Pedro
Pt Field
Pacifica
State
Beach
San
Pedro
Creek
PEDRO
POINT
Freshwater
marsh
Private beach
with public
shore access
Mr. Christian Murdoch Page 32
February 28, 2022

PEDRO FIELD
stairs

PRIVATE
BEACH
PUBLIC
ACCESS
Pedro
Pt Field
stairs
Mr. Christian Murdoch Page 33
February 28, 2022
Close-up of Coastal Access Stairs
Ongoing and persistent unpermitted Infill
Pre-agricultural historical features of Pedro Point and San Pedro Valley – 1869 - U.S. Coast Survey topographic map indicates Field to be Freshwater Marsh Excerpt of U.S. Coast Survey map of San Francisco Peninsula, 1869, based on 1850s topography: San Pedro Creek Valley and beach, now Linda Mar. Approximate location of Pedro Field (Calson/former Archdiocese property in red. Parallel horizontal hatched lines indicate freshwater marsh. Stippled shoreline area indicates sandy beach, dune, washover. Fine horizontal hatching is open freshwater (Lake Mathilda; historical Pedro Creek Lagoon, drained for agriculture 19th century).

Irregular circles/dots within marsh = wooded freshwater swamp (alder, willow).

Mr. Christian Murdoch Page 34
February 28, 2022
2010 Pedro Point Field Shoreline Trail (9/9/2010)
Approximate
location modern
San Pedro Field
PEDRO
POINT
SAN
PEDRO
VALLEY

FRESHWATE

R MARSH

FRESHWATER
MARSH (horizontal
hatching)

FRESHWATE

R SWAMP
Mr. Christian Murdoch Page 35
February 28, 2022
2008 PEDRO PT FIELD SHORELINE TRAIL (2/08/2008)
2005 PEDRO PT FIELD SHORELINE TRAIL (10/10/2005)
Mr. Christian Murdoch Page 36
February 28, 2022
2002 PEDRO PT FIELD SHORELINE TRAIL (9/30/2002)
1993 PEDRO PT FIELD SHORELINE TRAIL (9/30/2002)
Mr. Christian Murdoch Page 37
February 28, 2022
Attachment 6:

California Coastal Commission Denial of CDP 2-19-0026 (RHODES MIXEDUSE DEVELOPMENT) Exhibit 11 – Commission Staff Ecologist memo
From: Christine Boles [ ]
Sent: Monday, March 7, 2022 11:28 AM
To: Murdock, Christian [ Wehrmeister, Tina
[ Public Comment [ Bier, Mary
[ O'Neill, Mike [ Woodhouse, Kevin
[ Bob Boles [ ]
Subject: Bob Boles' DEIR comment letter regarding utilities Attachments: Bob Boles Comment Letter #1.pdf
[CAUTION: External Email]
Please see attached formal DEIR comment letter from my husband, Bob Boles. He is copied here so you can reach out to him directly with any questions.

Thank you,
Christine Boles, Architect
Beausoleil Architects
Pacifica, CA 94044
www.beausoleil-architects.com
“Do your little bit of good where you are; it's those little bits of good put together that overwhelm the world.” - Desmond Tutu
CAUTION: This email originated from outside of the City of Pacifica. Unless you recognize the sender's email address and know the content is safe, do not click links, open attachments or reply.
1 DATE: March 7, 2022
TO: Christian Murdock, AICP
Deputy Director of Planning
City of Pacifica Planning Department
540 Crespi Drive, Pacifica, CA 94044

RE: City of Pacifica General Plan and DEIR Comments, Utility section of DEIR Dear Mr. Murdock,
Please accept the following comments regarding the Utility related chapters noted above of the Draft General Plan and DEIR. I am a licensed architect with over 43 years of professional experience in design and construction, primarily in the local Bay Area. I have attached my current resume to validate my credentials1.

I believe the Draft Environmental Impact Report (DEIR) is fatally flawed and needs to be updated and replaced in its entirety and recirculated. I would normally leave my conclusions to the final paragraph, but in contrast to the one hundred and forty-nine page ‘Executive Summary’ of the DEIR, I’ll give my summary in one sentence:
_____________________________________________________________________________________ This DEIR is a mess: the data it is based on varies from recent to decades ago, it both leaves out important elements and duplicates others while providing conflicting information; it meanders around endlessly while providing platitudes instead of worthwhile information to determine impacts and appropriate mitigations to reduce proposed project impacts to a less than significant level as required by CEQA.
_____________________________________________________________________________________ My particular concern while reviewing the DEIR and Draft General Plan was the public utilities that the city provides: storm drainage, sewer system collection and treatment, water supply and waste/recycling.

A. General Comments

1. LU-I-13 “Public Service Priorities. Ensure that needs generated by development or uses permitted over the planning period are adequately served by existing and planned public works facilities.

In the event that existing or planned public works facilities can accommodate only a limited amount of new development, services to coastal dependent land use, essential public services and basic industries vital to the economic health of the region, state, or nation, public recreation, commercial recreation, and visitor serving land uses shall not be precluded by other development.” I see no analysis or discussion in any of the utility sections that confirms existing sewer, drainage, water, or waste system capacities or plans to upgrade/expand capacity to serve the projected buildout of 990 new units in the General Plan, much less the 1892 new units required under RHNA by January 2023, or the recent changes to state laws which allow ADU’s on virtually any residential lot and lot splits per SB 9 and 10, along with current developer proposals for high-rise residential development and proposed zoning amendments, annexations, and density bonuses. These growth projections must be presumed to have a considerably large error factor, which calls in question the very basis of the DEIR.

LU-I-13 acknowledges that development may need to be limited and yet gives no analysis how development may be limited. The Land Use Diagram Figure 4-3 increases density on a number of parcels scattered throughout Pacifica. For example, is the land proposed to be rezoned to Mixed Use 2 Neighborhood at the corner of Oddstad and Terra Nova a lower priority than Sharp Park as implied by LU-I-13 since it is not in the Coastal Zone? It seems the owner of that property would have a reasonable expectation based on the new General Plan zoning density change to Mixed Use Neighborhood that the property can be developed to increase density.

Are we making promises that we cannot necessarily keep and therefore exposing the city to potential litigation from that property owner if the city later denies his project based on inadequate utility capacity for example? How would you know if three other large projects in Sharp Park might be submitted the following month which would have priority and cap capacity? Or is the city then obligated to expend capital improvement funds we do not currently have on hand to expand our pump stations and sewage plant? We need a thorough evaluation of our capacity and ability to expand capacity as part of this DEIR. Please confirm how and when this will be provided.

By the way, this property, I believe identified as Park Mall, backs onto San Pedro Creek on the southern side – isn’t there a new DEIR policy that requires a 100-foot setback from a creek? Has that been considered? The parcel next to the creek is currently zoned agriculture (see below), which per the Growth Control Ordinance, requires a vote of the people to alter zoning. Please confirm why this parcel has been rezoned without this public vote.

2. Pacifica’s Limited Financial Resources for Expansion of Public Services.

The Bibliography on page 6-12 refers to “City of Pacifica Annual Budget 2011-2012. Available:
http://www. cityofpacifica.org/civica/filebank/blobdload.asp?BlobID=4400, accessed August, 2013.”
Please confirm what recent data and city budget were used as part of this DEIR and provide detailed information as to the city’s planning for both maintenance and expansion of utility infrastructure and additional land/sites for infrastructure needed to support actual project buildout over the next 8 years. We all know from Pacifica’s current Vision 2025 that the city is broke and in the next two to three years will not be able to serve current residents with essential services, much less future residents. Please identify and break out economic costs of new infrastructure needed, including new roads, fire stations, schools, sewer, water, stormwater systems, etc. required to achieve full Project buildout including RHNA housing allocation numbers so the City Council can make informed decisions as to our actual economic capacity for growth. 3 B. Sewage (wastewater) Collection and Treatment
I started by reviewing the Department of Public Works’ Sewage Collection System Master Plan, which dates to 2012, with a partial Update in 2021. I was glad to see what appeared to be a professionally organized document which described and mapped the components of the system. One of the goals of the Master Plan and particularly its Update was to model the system to assess its capacity with expected growth, and to point out what elements would need maintenance, repair or replacement, so that long term budgeting could be planned.

There are some problems with the Update as its’ projections for future flows are based on early 2021 knowledge of near-term developments (developments for which applications had already been made) which even a year later are severely out of date, and on the assumptions about open developable land based on “allowable density in the general plan”, presumably the 1980 General Plan which is still in effect.

Project Implementation Recommendations on Page ES-7 of the Sewage Collection System Master Plan confirms that these growth projections, including the Sharp Park Specific Plan, are not included in the current analysis.
“Growth projections assumed herein should be updated as needed to reflect the City’s General Plan and Sharp Park Specific Plan updates, which are currently ongoing, and need to meeting regional housing needs. Based on the Draft Regional Housing Needs Allocation (RHNA) Plan for the San Francisco Bay Area, prepared in May 2021, the City must plan to accommodate a total of 1,892 new households between 2023-2031 to meet regional housing needs;”
The DEIR is based in part on these Master Plan documents so it is likewise subject to a large error factor.

1. Please clarify and provide detailed calculations and analysis to show how the Project Buildout number was obtained, where the various additional units are proposed to be located, and confirm the number of additional housing units possible given our current sewage system capacity. If additional sewage capacity is needed to meet projected buildout, please confirm how and where our existing plant might be expanded, which pump stations would need to be upgraded, at what projected cost, and how the city is planning to secure these funds. I see no discussion of this in the General Plan or DEIR. Please also note that current development fees for sewage and storm water improvements have not been updated in some time and are woefully inadequate.

2. Due to the date of its publication, the Update also makes no mention of the recent Linda Mar flooding and the massive spills of recent untreated sewage into the Pacific Ocean in October and December of 2021. This is the elephant in the room – the fact that the Equalization Basin hasn’t done the job it was intended for even with current demand, much less with any projected growth.

Please provide detailed information and calculations showing the capacity of the Equalization Basin and detail any proposed improvements to increase capacity.

3. Looking at the DEIR section for sewage, and assuming it would be based on the latest information available, I was astonished to see in the Environmental Setting section, on page 3.13-5, under the heading Usage and Capacity, the phrase “Flows are projected to rise to 3.2 mgd by 2012”, and that this datum based on the General Plan Update Wastewater Treatment Service Provider Form from 2009.

Wait, our new general plan is written in reference what was supposed to happen starting 10 years ago? From a study which is 13 years old? This calls into question the rest of the utility section – how much of it is actually current and pertinent to today and the next 20-40 years? Does it need to be refreshed with current data? If the recommendations are based on a document written thirteen years ago, then the document is fatally flawed and needs to be rewritten. 4 4. Another example, on page 3.16-6: table 3.13-2 says it “represents the most recent wastewater data that was available…”, but the source listed is the Sewer Collection Master Plan, 2011. Please update analysis and findings per current source material from 2012 and 2021.

5. Under the Planned Improvements heading, several items are listed that “…the City intends to undertake…” The list is from 2009. Have these projects already been done? Are they still pending? Are there new projects in the works to increase capacity and provide resilience from climate change impacts? Please clarify and update the documents accordingly with current information.

6. Reading on, in the section entitled IMPACT SUMMARY, starting on page 3.13-16, the DEIR does reference the more recent data in the 2021 Update. But on page 3.13-17, data from BOTH 2006 and from 2021 are referenced! Please review and clarify that there are no discrepancies between these references that would impact the proposed Project or cause confusion for developers or planning commissioners utilizing these documents as references for the next 20-40 years.

7. CO-I-23 “Wastewater Treatment Capacity. Continue to monitor wastewater generation rates so decision-makers are aware of the impacts on the treatment plant on new development, and plan for additional capacity in advance of projected need.”
Again there are no details, enforcement, or budgeting described to implement this vague policy.

Please expand.

C. Storm Water System
I was unable to find a Master Plan for the city’s storm water system. I understand from Public Works Director Lisa Peterson that a consultant has been hired and this is being worked on now. I therefore dug into the DEIR directly.

1. Storm drains are (briefly) described on pages 3.13-6 and -7, in the Environmental Setting section, as comprising 290,000 linear feet of piping and 989 inlets with two pump stations. There aren’t any hints to the age of the data, but the data points listed are at least in conformance with the storm drain description on the city’s website. Creeks are mentioned as a destination for storm water, but no mention is made of the open swales and drainage channels that are an important part of the storm water system. Isn’t a natural creek that handles the city’s storm drainage part of the storm drainage system? Please add this information as necessary to the DEIR.

2. Further on, on page 3.13-19 in the IMPACT SUMMARY section, the storm drain system is described again: “The system serves 178 miles of roads and 986 inlets”. Oops, lost three inlets, but then again, this data is from 2008 so maybe we gained 3 outlets in the meantime? It’s curious that, as there is commonly about one foot of storm drain piping per foot of road, this would seem to entail about 940,000 linear feet of piping…but then I know from personal experience that, at least in my own neighborhood, the official storm drain block books are sometimes blank. It’s not clear that anyone knows just how big the system is. Please complete the Storm System Master Plan and incorporate this important information in the DEIR and General Plan, even if it needs to be done as an amendment next year. For now, please add a note as appropriate in the DEIR and GP that this information is incomplete and will need to be amended.

3. The DEIR concludes that the Plan (not sure exactly what plan is being analyzed here; sometimes a ‘plan’ is referred to, sometimes ‘the project’) will incorporate best storm water practices in new projects and doesn’t envision any changes to the existing infrastructure; therefore, there will be no environmental impacts. There seems to be no thought of climate change and its effect on rainfall.

Shouldn’t an Environmental Impact Report take nature into account? Increased rainfall intensity should be evaluated and planned for as part of SB379’s climate change vulnerability assessments and adaptation planning. Please add this critical information to the DEIR and GP. 5 Perhaps the editors should be made aware of the City’s recent Request for Proposals to Civil Engineering Consultants for a Storm Water Master Plan. Among other scopes of work, it calls for this (emphasis added):

“Deficiencies in the Storm Drain System - Assess conditions of storm drain infrastructure and determine capacities of existing storm drain facilities; include identification of isolated flooding locations, and determination of capacity improvement needs. Flooding has occurred with greater frequency in recent years – a trend that can be expected to continue due to several factors, such as weather events of greater severity (related to increased ocean water temperatures) and sea level rise.”

4. The city engineers seem to know the score, have they reviewed this DEIR prior to recent publication? Please provide copies of Public Work’s review and input of these current documents.

D. Flooding

1. In a subsequent section, on page 3.13-12, the City’s Flood Damage Prevention Ordinance is mentioned. That dates to 2017. Can you confirm whether this ordinance, the DEIR and the draft Safety Element comply with the requirements of Government Code Section 65302(g) (2) which I have copied below for reference. I am still slowly wading through the General Plan documents, but have not seen all these items addressed, for example flooding risk in Sharp Park without the sea wall, and flooding risk in Fairway Park without the berm, repeated flooding of Linda Mar as recently as October and December 2021. What is the flood history and current flood risk to the Linda Mar Fire Station #72, which is located very near San Pedro Creek? What about the Milagra Fire Station? I believe that area has also had a history of flooding and sink holes? “The safety element, upon the next revision of the housing element on or after January 1, 2009, shall also do the following:
(A) Identify information regarding flood hazards, including, but not limited to, the following:
(i) Flood hazard zones. As used in this subdivision, “flood hazard zone” means an area subject to flooding that is delineated as either a special hazard area or an area of moderate or minimal hazard on an official flood insurance rate map issued by FEMA. The identification of a flood hazard zone does not imply that areas outside the flood hazard zones or uses permitted within flood hazard zones will be free from flooding or flood damage. (ii) National Flood Insurance Program maps published by FEMA. (iii) Information about flood hazards that is available from the United States Army Corps of Engineers. (iv) Designated floodway maps that are available from the Central Valley Flood Protection Board. (v) Dam failure inundation maps prepared pursuant to Section 6161 of the Water Code that are available from the Department of Water Resources.
(vi) Awareness Floodplain Mapping Program maps and 200-year flood plain maps that are or may be available from, or accepted by, the Department of Water Resources. (vii) Maps of levee protection zones.
(viii) Areas subject to inundation in the event of the failure of project or nonproject levees or floodwalls. (ix) Historical data on flooding, including locally prepared maps of areas that are subject to flooding, areas that are vulnerable to flooding after wildfires, and sites that have been repeatedly damaged by flooding. (x) Existing and planned development in flood hazard zones, including structures, roads, utilities, and essential public facilities.
(xi) Local, state, and federal agencies with responsibility for flood protection, including special districts and local offices of emergency services.
6 (B) Establish a set of comprehensive goals, policies, and objectives based on the information identified pursuant to subparagraph (A), for the protection of the community from the unreasonable risks of flooding, including, but not limited to:
(i) Avoiding or minimizing the risks of flooding to new development. (ii) Evaluating whether new development should be located in flood hazard zones, and identifying construction methods or other methods to minimize damage if new development is located in flood hazard zones. (iii) Maintaining the structural and operational integrity of essential public facilities during flooding. (iv) Locating, when feasible, new essential public facilities outside of flood hazard zones, including hospitals and health care facilities, emergency shelters, fire stations, emergency command centers, and emergency communications facilities or identifying construction methods or other methods to minimize damage if these facilities are located in flood hazard zones.
(v) Establishing cooperative working relationships among public agencies with responsibility for flood protection. (C) Establish a set of feasible implementation measures designed to carry out the goals, policies, and objectives established pursuant to subparagraph (B).”

2. SA-I-24 Storm Drainage Impact Assessment. “Require developers to provide an assessment of a project’s potential impacts on the local storm drainage system as part of the development review process. If development is found to have a negative impact on storm drainage, the City should require applicable and e!ective mitigation measures, such as the creation of permanent or temporary detention or retention basins, provision of additional landscaped areas and green roofs, installation of pump stations, and the use of permeable paving in drive-ways, walkways and parking areas.”
Please clarify how the city will define “local storm drainage system”. Would that include all the downstream storm drains, roads, and pump stations to the point of treatment?

3. Figure 3.5-1 Hydrology and Flood Zones neglects to show the flow of Big Inch Creek between the homes on Monterey and Nelson, undergrounding at Ocean Shore School. This is also an area that regularly floods from storm water runoff, despite being on a hillside. The creek banks are also eroding in several areas, as recently documented by Christine Boles with extensive photos, videos and over 30 neighbor testimonials. This data was shared with Public Works on 12/2/2021.

7 4. CO-I-3 Funding for Creek Maintenance. “Establish funding mechanism to require property owners with land adjacent to creeks to pay proportionate share of creek improvement maintenance.” I strongly object to this requirement as written. When creeks are part of the local hydrology and used for drainage, they benefit the entire community in the watershed, not just the properties that back onto the creek. Responsibility for maintenance should be shared by all the properties within the watershed, which is easily identified now with Figure 3.5-1 above.

I’d also like to call into question Section 6-12.208 of the PMC “Every person owning property through which a watercourse passes, or such person's lessee or tenant, shall keep and maintain that part of the watercourse within the property reasonably free of trash, debris, excessive vegetation, and other obstacles which would pollute, contaminate, or significantly retard the flow of water through the watercourse.” From surveying our neighbors on Monterey Road and Nelson, not everyone can access the creek from their back yards due to steep friable banks or tall retaining walls. This means that large sections are not maintained. This maintenance should therefore be the responsibility of public works, who can access the creek from the large gates at the cross streets, which residents cannot access. Again, costs can be shared by all the watershed properties in a newly created special assessment district. I also wanted to point out that there was no disclosure of this maintenance requirement in our purchase papers when we bought our property.

E. Water

1. “CO-G-5 Water Conservation. Work with the Water District to meet State targets for reducing per capita urban water use by 10 percent by 2015 and 20 percent by 2020.” Please revise to include appropriate targets for FUTURE dates. Were the water reduction goals listed above achieved in 2015 and 2020? The current data actually shows water use has increased to its highest level in 2019-2020. What does the water use data show for 2021-2022?

2. CO-I-22 Water Storage. “Support the NCCWD in its efforts to provide adequate emergency water storage in Pacifica.”
Do we have adequate amounts of water storage? NCCWD is not currently planning for growth of 990 new units or 1892 new units under RHNA in the 2020 Urban Water Management Plan.

Are the large, heavy water tanks located on hillsides secure in the event of a substantial seismic event? This analysis is missing from the public documents the NCCWD has released to date. 8 3. The Bay Delta Plan may significantly lower available potable water to Pacifica – where is this discussed in relation to possible limits to new housing? What about droughts limiting water hookups, which is discussed in the NCCWD’s 2020 Urban Water Management Plan? Should that not be included in the DEIR especially as it relates to climate change adaptation and resiliency as required by SB379?
F. Waste/Recycling

1. ES-I-4 Recycling Center Relocation. Work with Recology, Inc. to identify a new location for a recycling yard to free up land for visitor-based economic development.

The current Recology location is in an area experiencing high erosion of coastal cliffs. This is an essential public health and safety issue and it is not discussed at all in the DEIR or General Plan. A new location should be identified now as part of resiliency planning under SB379, not at some vague time in the future. Please provide a discussion/plan for resolving this issue along with a plan to address the potential loss of Palmetto Avenue in this location across from the current Recology site due to projected Coastal Erosion.

2. “6-G-6 Adequate Infrastructure. Manage utility infrastructure and waste management systems that are adequate to protect the health and safety of all current and future Sharp Park residents and businesses.”
First of all, is this item numbered properly? It seems different than other Guiding or Implementation Policies. Secondly this is so vague it is meaningless. Utility infrastructure in Sharp Park will need to be moved inland for resiliency from sea level rise. Please provide a discussion of when and where infrastructure will be moved, and identify an inland site for the relocation of Sharp Park Sewage Pump Station.
9 The Sharp Park Sewage System serves approximately 40% of the population of Pacifica, well beyond the boundaries of Sharp Park. With a pump failure, waste backup could reach every corner of the sewer system. Even with triggers and a plan in place by that time, it would take years to add details to finish the plans, raise the money, process the permits through the Coastal Commission, and actually complete moving the sewer system landward. By waiting so long to complete the rebuild the cost could double or triple what it would cost if done in the near future.

The lack of any current plan to move the pump station as part of this General Plan or of the Beach Boulevard Infrastructure Resiliency Project seems negligent on the part of the city of Pacifica, and is most certainly not building long term resiliency from climate change effects of sea level rise and coastal erosion.

In conclusion, all public service and utilities impacts should be found to be significant and unavoidable unless new analysis is provided that services and utilities can meet the demands of the full development allowed by the Proposed Project (much more than 990 units as demonstrated in detail by Planning Consultant Terry Watt)
I urge you to pull the documents, update them properly and consistently with current data in consultation with Public Works and Wastewater divisions, NCCWD and Recology, organize the documents clearly with proper indexes and tables of contents and an updated Bibliography; recirculate them as necessary, and hold public hearings to study them. These are important documents and need to be properly prepared and publicly vetted in a fair and reasonably manner. We cannot possibly approve a General Plan with 990 new units (or more under RHNA) without a proper understanding of our infrastructure capacity as well as the necessary improvements for climate change resiliency and adaptation.

Sincerely,
Robert Boles, Architect
License
Principal
Cc: Honorable Mayor Mary Bier
Tina Wehrmeister, Planning Director
Kevin Woodhouse, City Manager
1 Robert Boles Resume

ROBERT ALLEN BOLES, ARCHITECT
Professional Registered California Architect, 1986, License No.

Status

University California Polytechnic State University, San Luis Obispo Education: Major in Architecture, 1976-1979. B.Sc. Arch. with Honors, 1979 University of California, Berkeley
Major in Architecture 1974-1976
Continuing City College of San Francisco, REVIT 3d drafting, 2014 Education: PG&E Energy Center, Photovoltaic design and financing, solar thermal heating, ventilation, building envelope courses, 2006-2018 Sydney University of Technology AutoCAD training course, 1990 U.C. Berkeley Extension Course in Real Estate Development, 1989 East Bay AIA Project Management Seminar Series, 1988

Consultant Beausoleil Architects, 1992 - present
Experience: Residential projects, new and remodel
Hotel/motel projects, new and remodel
Corporate interiors projects
Retail and restaurant projects
New religious institution campus project
Employment: Patri Merker Architects, San Francisco, CA 1997-1998 Senior Project Architect responsible for renovation of existing landmark financial district office building into new 360 room Omni Hotel. Additional work included detailing assistance on new Macy*s Union Square buildings ArcusStone LLC, Hayward, CA 1995-1997
Staff Architect responsible for client contact, project design, project estimating, development of product literature and new product development Davenport Campbell Pty, Ltd., Sydney, Australia, 1989 - 1991 Senior Project Architect on World Square Hotel, Sydney. Architect on Oceanic International Hotel, Sydney and Magic Kingdom Theme park, Sydney Stong and Associates, Architects, San Francisco, 1987- 1989 Project Architect, Project Manager, Project Designer on auto dealership, office building, church, corporate interiors, and residential projects Page, Clowdsley and Baleix, San Francisco, 1982 - 1986
Architect, Designer/Draftsman on corporate interiors and industrial projects Mike Corbett, Master Builder, Davis, California, 1979-1982 Designer/Draftsman of residences at nation’s first all-solar heated subdivision, new town planning projects
Interests: Alternative Energy, Home Improvements, Community Theater, Citizen Science From: Christine Boles [
Sent: Thursday, January 27, 2022 10:23 AM
To: Murdock, Christian [[email protected]]
CC: Woodhouse, Kevin [[email protected]]; Wehrmeister, Tina [[email protected]]; Bier, Mary [[email protected]]; Public Comment [[email protected]]
Subject: Boles DEIR public comment letter #1 regarding documents and process Attachments: Christine Boles DEIR comment letter #1.pdf [CAUTION: External Email]
Please see attached. Note that I'll be filing a PRA request for the recent communication with the Department of Fish and Wildlife.

Christine Boles, Architect
Beausoleil Architects
Pacifica, CA 94044
www.beausoleil-architects.com
“Do your little bit of good where you are; it's those little bits of good put together that overwhelm the world.” - Desmond Tutu
CAUTION: This email originated from outside of the City of Pacifica. Unless you recognize the sender's email address and know the content is safe, do not click links, open attachments or reply.
♦ Pacifica, CA 94044 ♦ Tel ♦
DATE: January 27, 2022
TO: Christian Murdock, AICP
Deputy Director of Planning
City of Pacifica Planning Department
540 Crespi Drive, Pacifica, CA 94044

RE: City of Pacifica General Plan and DEIR Comments, letter #1, process and unusable documents Dear Mr. Murdock,
I would like to officially record my objections to the 45-day public review process given the poor quality of the documents posted on the Plan Pacifica website for public review on January 7, 2022 at approximately 10:30pm.

Please reference the email to council from Pete Shoemaker sent on January 23, 2022, which I have copied below, and which you can see my name is officially signed on to. I also reference my previous email to you on 1/20/22 with a specific example of the difficulties I am facing in using these documents related to Greenhouse gas emissions.

After substantial public outcry, the city made available searchable word documents on 1/25/22, but at that point we had already lost 17 out of 45 days of our already minimal review period the city has allowed. The fact that the Word documents contain text but not graphs or other visuals means that they are still difficult to use and take more of our time as we are forced to go back and forth between documents and formats. This is unprofessional and an unnecessary burden to both residents and state and local agencies tasked with reviewing these documents.

In fact, I received a phone call from Will Kanz of the California Department of Fish and Wildlife yesterday afternoon. Their department is also having issues with not being able to search documents, and with not being able to cut and paste from the pdf to prepare their official comments and responses. He told me he had sent the city a letter requesting an extension, but that the request was denied. On what grounds what this request denied? I would like to remind city staff and Council that the basic purpose of these documents, as described in the DEIR introduction Section 1.1, is to “inform decision makers, responsible and trustee agencies, and the general public of the proposed action and a range of potential environmental impacts of that action. The EIR process provides (is supposed to provide) an opportunity to identify environmental benefits of the Proposed Project that might balance some potentially significant adverse environmental impacts.” It is not only in all of our interests to ensure these documents are properly prepared and reviewed, but also our utmost duty as the current stewards of this land we coinhabit. How can honestly claim at the beginning of each Council meeting to honor the Ohlone Ramaytush peoples whose land we profess still belongs to them without a full and robust review and engagement process on these most critical environmental documents.

I urge you to pull the documents, fix the pdfs as previously requested, and reset the 45 day clock.

Sincerely,
Christine Boles, Architect
Principal
♦ Pacifica, CA 94044 ♦ Tel ♦
Cc: Honorable Mayor Mary Bier
Tina Wehrmeister, Planning Director
Kevin Woodhouse, City Manager
[email protected]
From: Pete Shoemaker <
Subject: Updated GP and EIR documents that you can navigate: Uncovering more serious problems Date: January 23, 2022 at 11:42:00 AM PST
To: "Bier, Mary"
<[email protected]>, [email protected], [email protected], [email protected], sbeckmeyer @pacifica.gov
Cc: [email protected], [email protected], [email protected], [email protected] ca.ca.us, [email protected], [email protected], [email protected], "Wehrmeister, Tina" <[email protected]>, Christian Murdock <[email protected]>, "Woodhouse, Kevin" <[email protected]>, "O'Connor, Bonny" <[email protected]> Fellow Pacificans,
Out of necessity I have added interactive Tables of Contents to the GP and EIR so people can actually examine the files that City Staff is asking to be approved as the most important documents in Pacifica. The deficiencies of the draft EIR are clearly visible and even worse than I thought: in addition to having no reasonable TOC, the search function does not work accurately. The attached PDF file gives download links and this short video shows the details: Video
All of you care about Pacifica and want to serve your city well. City Councilmembers have taken an oath to faithfully represent the people. I don’t see how anyone could, in good conscience, approve this current version of the DEIR as acting in the best interest of the citizens of Pacifica. I understand there have been staff shortages, but this document appears to have been rushed through without sufficient editing or scrutiny.

We are facing unprecedented challenges in the form of climate change. We need have the best of tools and the best of communication to deal with what’s ahead. The clear course of action is to remove the DEIR, bring it up to professional standards as we’ve specified, then re-release it and restart the comment period.

Pete Shoemaker
------------------------------------------------------- On Jan 17, 2022, at 7:50 PM, Pete Shoemaker < wrote:

City Council (cc: Planning Commissioners),
We the undersigned are attempting to do what the City asks of us, and review and comment on the General Plan and DEIR. We are encountering major problems. Here is a short video that outlines these problems and offers simple, quick, and very low-cost solutions that will save us, you and many other people much time and stress. Please look it over and direct staff to follow its suggestions, which are also listed in the attachment.

Video: https://www.screencast.com/t/MTP215Miguq
<GP - EIR solutions.pdf>
Pete Shoemaker
Danny Estrella
Sue Schectman
♦ Pacifica, CA 94044 ♦ Tel ♦
Deborah Lynch
Dinah Micheletti
James Kremer
Elisabeth Boles
Cindy Abbott
Suzanne Moore
Peter Loeb
Dinah Verby
Summer Lee
Mark Hubbell
Cherie Chan
Stan Zeavin
Clif Lawrence
Marijo Van Dyke
Marj Davis
Christine Boles
Some reactions below…
From: DEBORAH LYNCH < com>
Subject: General Plan docs - EIR
Date: January 14, 2022 at 3:13:41 PM PST
Hi Pete,
I tried to navigate through the General Plan and gave up. It seems to me that was the desired reaction by our local government. I am willing to sign a petition or help to do what is necessary to correct this. Please let me know what I can do to assist. We all need access to this information!! Thank you,
Debbie Young Lynch
From: Danny Estrella < >
Subject: Video on Pacifica GPU document review
Date: January 15, 2022 at 3:20:29 AM PST
Hi Pete,
I want to thank you so much for your video of reviewing the Pacifica GPU. You took what is a dreadful, tedious exercise and presented it in a humorous way while explaining the shortfalls and resolution clearly and explicitly. It appears to me that the City's preparation of the GPU is at best incompetent and at worst deviously deceptive. I hope your video is widely viewed and appreciated across the City.

Highest regards,
Danny Estrella
From: " " < com>
Subject: Sign my name to your letter to the city re the GPU Date: January 14, 2022 at 2:54:31 PM PST
Hi Pete,
Your video was funny but sad. I'm happy to sign a letter asking for a userfriendly document(s).

Dina Micheletti
♦ Pacifica, CA 94044 ♦ Tel ♦
Pedro Point
From: Sue Digre < >
Date: January 13, 2022 at 6:53:38 PM PST
Love it Pete. I thought I had troubles because I am not techy.

This video will help people not to be frustrated. THANKS From: Marijo Van Dyke < >
Subject: Re: CPUP meeting tomorrow Friday the 14th, 10 am: Video for review
Date: January 13, 2022 at 5:37:10 PM PST
This document is just beyond belief. It is incomprehensible. I'm a retired city planner and I am embarrassed for Pacifica.
1 From: Monica Meagher [
Sent: Tuesday, March 8, 2022 4:01 PM
To: Public Comment [[email protected]]
CC: Jarl Meagher [
Subject: City of Pacifica Draft General Plan
Attachments: Meagher - Pacifica General Plan Comments.pdf [CAUTION: External Email]
Please see our comments in the attached letter.

We appreciate your time!
Jarl and Monica Meagher
CAUTION: This email originated from outside of the City of Pacifica. Unless you recognize the sender's email address and know the content is safe, do not click links, open attachments or reply.

March 8, 2022
RE: City of Pacifica Draft General Plan
Christian Murdock, AICP,
Deputy Director of Planning
City of Pacifica Planning Department
540 Crespi Drive
Pacifica, CA 94044
Dear Mr Murdock,
Thank you for the opportunity to provide public comments on the City of Pacifica Draft General Plan. We have lived in Pacifica for close to a decade and are delighted to call the city our home.

It is a wonderful place to raise a family, enjoy open views, and spend time outside at the beach or in the water. We are excited to see the thought and planning into making Pacifica an even better place to live and visit.

It is clear from the Draft General Plan that the city is mindful of preserving a large amount of open space, and focusing on dense, high uses for vacant or undeveloped space. There is also clear thought put into better utilizing currently developed land. We appreciate the balance of open space and smart development.

We love and fully support the plans to further develop Palmetto Avenue into a retail and visitor destination. We try to spend as much money locally as possible. This is very easy with the many restaurant options, local grocery store, and recently, a few local toy stores. However, this is difficult for home goods and sundries. We’d love to see options for sustainable home goods that we can purchase locally and hope a revitalized Palmetto Avenue is attractive for retail.

It is also clear that Pacifica is car centric. This has become a chicken and egg problem. Since Pacifica does not invest as heavily in walking, biking, and transit, people must drive; therefore we are a car centric town that does not invest heavily in alternatives. We appreciate the focus beyond cars and considerations for pedestrians, bicycles, and transit. We hope the city prioritizes planning for alternative modes before investing further in car infrastructure. This will start to shift the balance and allow residents to use alternative modes to get around town. The Draft General Plan notes that all studied intersections have crosswalks. However, there is no crosswalk across Esplanade Avenue at any point, which makes it very dangerous for the many pedestrians trying to get to the walking path to enjoy the view. We hope this is addressed.

We appreciate the Existing and Proposed Bike Network but did notice some discrepancies between current conditions and what is marked on the map, especially regarding the north section of Palmetto (between Ingrid B Lacey and West Avalon) and Esplanade. There is one “bike path” sign and no road markings on Esplanade so we are surprised to see it classified as a bike path. There are many bikers who use that portion of the road and have difficulty navigating around parked cars. The path does not link up to the well created paths along Palmetto. We would love to see the path on Esplanade updated and linked to the rest of the city. We think many residents would bike around town to shop locally with safer and connected bike paths. We hope Pacifica will look to Berkeley as an example for safe, usable bicycle paths.

It is also clear from the small number of transit trips today that Pacifica can benefit from better connections to the world-class transit available just over the hill. The Linda Mar Park N Ride is a great example of what can be done, but could be executed better. If a Linda Mar resident wanted to park and bus to BART, they would have to stop 36 times between Linda Mar and BART. Even someone from the north end of the city would need 22 stops. Pacifica should partner with SamTrans to make an effective connection to BART with fewer stops for Pacifica residents. Rather than providing more stops, reduce stops to serve just a few central Park N Ride locations to make for a fast commute to BART or Caltrain. Park N Ride facilities can be located in the major residential areas (Manor, Sharp Park, Linda Mar) and Limited stop or Rapid bus lines can be used during commute times to supply buses just stopping at Park N Ride locations. These same locations could be used on weekends (with the addition of Rockway) to provide trolleys or some festive way for BART or Caltrain riders to access Pacifica beaches on the weekends. Again, minimizing stops (rather than expanding services) to just be in key commercial areas for visitors and residents. We would happily take our family via transit down to Linda Mar for a beach day rather than struggle with parking if there was only one stop along the way.

These suggestions around walking, biking, and transit align with the Caltrans’ Smart Mobility Framework for suburban locations. It recommends the prioritization of transportation projects and programs that:
- Invest in complete streets and safer walking and biking conditions - Increase commute transit service and ridesharing
- Improve connectivity to reduce trip lengths and increase non-auto trips In line with the last suggestion, we would like to suggest clearer prioritization. There are many policies outlined in the Draft General Plan. While we hope the city is able to realize them all, we must be mindful of our limited resources (of both time and money). Can the city work to balance various needs and make it more clear which policies are priorities? There should only be a handful in order to be effective.

We are delighted to call Pacifica our home and hope to support many of the wonderful policies outlined in the Draft General Plan. Should you have any questions regarding our comments, please reach out to us at Thank you for your consideration.

Sincerely,
Jarl and Monica Meagher
Pacifica Residents
From: jewel walli [
Sent: Saturday, March 5, 2022 7:37 AM
To: Murdock, Christian [[email protected]]; _City Council Group [[email protected]]
Subject: City Plan
[CAUTION: External Email]

1. Please include some recreation requirements in the approval of new building permits for those large complexes that are being discussed. We are a city with no public tennis courts/pickle ball courts.

2. In the general plan please include some pickleball courts . Work with the Parks and Recreation department and start applying for grants. This sport, most popular in America, appeals to older adults so there are probably grants available.

3. Negotiate with the High School District and go in jointly with a new library. Oceana and Terra Nova have a lot of unused land (That would work for some public pickleball courts as well).

4. Quit approving buildings (like the church) that have a huge negative impact on the residents that live there. Would you want a house on Cape Brenton? Thank you.

CAUTION: This email originated from outside of the City of Pacifica. Unless you recognize the sender's email address and know the content is safe, do not click links, open attachments or reply.

From: Christine Boles [
Sent: Tuesday, March 8, 2022 4:16 PM
To: Murdock, Christian [[email protected]]; Wehrmeister, Tina [[email protected]]; Woodhouse, Kevin [[email protected]]; Bier, Mary [[email protected]]; Public Comment [[email protected]] CC: Berman, Lauren [[email protected]]; Nibbelin, John [[email protected]]; Hauser, Samantha [[email protected]]; Leal, David [[email protected]]; Godwin, James [[email protected]]; Domurat, George [[email protected]]; Ferguson, Alex [[email protected]]; Rexing, Stephanie@Coastal [ KoppmanNorton, Julia@Coastal
[
Subject: Comment Letter #5
Attachments: Christine Boles Comment Letter #5.pdf
[CAUTION: External Email]
Please find attached DEIR letter mostly related to the Sharp Park Specific Plan and other potential sites for increased density for housing.

Feel free to reach out to me with any questions.

Christine Boles, Architect
Beausoleil Architects
Pacifica, CA 94044
“Do your little bit of good where you are; it's those little bits of good put together that overwhelm the world.” - Desmond Tutu
CAUTION: This email originated from outside of the City of Pacifica. Unless you recognize the sender's email address and know the content is safe, do not click links, open attachments or reply.
478 Monterey Road ♦ Pacifica, CA 94044 ♦ Tel ♦ www.beausoleil-architects.com DATE: March 8, 2022
TO: Christian Murdock, AICP
Deputy Director of Planning
City of Pacifica Planning Department
540 Crespi Drive, Pacifica, CA 94044

RE: City of Pacifica General Plan and DEIR Comments, letter #5, DEIR questions related to Sharp Park Specific Plan and other miscellaneous items
Dear Mr. Murdock,
Please accept my preemptive apology that these comments are not well organized or complete, but my time is limited due to today’s deadline. I have a number of concerns and questions about the City’s focus on Sharp Park as the preferred project for concentrating development increases. The Sharp Park areas is heavily burdened due to environmental, climate change and safety factors, and I wonder if it is really the best place to put all of the city’s energy into redevelopment. Below are my concerns, not in any particular order of importance.

1. As mentioned previously in my Comment Letter #2, detailed maps of projected coastal erosion and sea level rise are missing from both the DEIR and General Plan. In fact, the city’s own Existing Conditions Report from July 2010 showed much better maps to help decision makers and developers analyze these conditions, in that they are more complete. Using less complete information in subsequent updates leaves the City vulnerable to confusion and lititgation by artificially adding perceived value by rezoning to higher allowed densities.
♦ Pacifica, CA 94044 ♦ Tel ♦

2. In addition, the City’s hired consultant, ESA, in the 2018 Sea Level Rise Vulnerability Assessment provides even more detailed information about coastal erosion and sea level rise projections. There is no link to this document in the DEIR and it is not listed in the Bibliography. Please add the references to ensure we are working on the same information. The copy I have of this report is dated January 2018 and is labeled DRAFT. Has this report been finalized with the consultant and approved by the City Council? Why were these maps not incorporated into the DEIR and GP Safety Element when sea level rise and coastal erosion are some of our greatest hazards, and have already cost the city greatly in lost housing and fees to tear down inappropriately built structures?

3. I spoke with one of the report authors at ESA about a year ago to try to understand the map in Sharp Park in particular. I was confused because there is no storm flood area shown in the diagram when I have personally observed major flooding along Beach Boulevard and the properties across the street from the ocean in winter storms and king tide events. I was told that flooding was not analyzed due to the presence of the sea wall. I would suggest that this issue needs further scientific study and mapping to understand the real hazards in this area and this information needs to be added to the DEIR.

4. In addition, new development cannot be permitted in the Coastal Zone that relies on a sea wall or other armoring, which makes it imperative to redo this modeling without a sea wall in place. In previous letters I have documented that this is actually a state requirement for General Plan Safety Elements for flood areas. As these properties in the Coastal Zone must be designed for 100-year life, which is 50 years beyond the design life of the sea wall currently being proposed, this modeling is essential to understanding how building design life criteria can be met.

Specifically, Section 30253 prohibits new development if it would require a coastal armoring structure:

New development shall do all of the following:
(a) Minimize risks to life and property in areas of high geologic, flood, and fire hazard.
(b) Assure stability and structural integrity, and neither create nor contribute significantly to erosion, geologic instability, or destruction of the site or surrounding area or in any way require the construction of protective
devices that would substantially alter natural landforms along bluffs and cliffs.

5. Below is the map of the Sharp Park Area from this ESA study, showing considerable threat. I have roughly overlaid the map with the areas indicated on Figure 4-3 Land Use Diagram, to be the highest density allowed, where height is increased to 55’ or more (there was one reference to more than 55’ somewhere that I can’t find now) with the provision of low-income housing. Note that several of these overlap these high hazard zones. I believe the General Plan Safety Element calls for avoidance of building in high hazard areas.

Please remember that the Coastal Commission needed to assert jurisdiction over the Coastal Zone, and overturned the City of Pacifica’s questionable approval of Coastal Development Permit Application Number CDP-395-18, which had been previously green-lighted by the City, despite numerous objections and appeals by local residents who had pointed out the obvious hazards at 1567 Beach Blvd Pacifica. Failing to provide current information to the public further endangers Pacificans, misleads developers who wish to build sustainably in good-faith, and wastes staff and the public’s time and taxpayer funds. So, I would question the validity and wisdom of the current proposed land use maps for this area.
♦ Pacifica, CA 94044 ♦ Tel ♦

6. I am pretty certain there are restrictions about placing--or concentrating--vulnerable low-income population in areas of high hazards. If not, there are moral issues with placing vulnerable residents in the highest-risk areas. Please confirm and add appropriate conditions in the Land Use Element to comply with applicable laws, and explain how these could possibly be in conformance with the State’s Environmental Justice goals.

7. Please also note that Palmetto Avenue is threatened by sea level rise on the southern end. I have seen no discussion of the possible need to move the road and infrastructure inland. This should be discussed now before new high-density construction is allowed on the inland side of Palmetto.

8. As previously mentioned in Comment Letter #4, our sewage infrastructure will eventually need to be moved inland. Our sea wall consultant GHD specifically said that the sea wall would not protect us long term, it is only being designed with a 50-year life to buy us time for more wholistic and long-range resiliency planning. An alternate site for the Sharp Park Sewage Pump Station that serves the entire northern section of Pacifica must be identified now as part of this General Plan. Perhaps the city’s Salada parking lot would be a good location, but that is also zoned Mixed Use Center. This property has also recently been approved as part of the Civic Center Remodel as required parking for those buildings, so perhaps we need to find an alternate site?

9. SA-I-26 Tsunami Evacuation Zone. For new development in the tsunami evacuation zone, require use of low impact engineering techniques, such as elevating structures above projected water levels, to mitigate impacts to people and structures.

My understanding from my limited experience with the Coastal Act is that new development is not strictly prohibited in Tsunami Evacuation zones or areas with or projected flooding from sea level rise or seasonal rains, but that the structures and roads must be adaptable and allow the water to pass through. Their ground floor levels also need to be raised above projected sea level rise. These requirements and basic protections are missing in the DEIR, and are also conspicuously absent from the consultant’s pretty renderings of what Sharp Park development might look like under this General Plan.

These basic requirements will completely change the relationship of the buildings to the street and ♦ Pacifica, CA 94044 ♦ Tel ♦
require long handicapped ramps that require considerable space (1 foot of length for every inch of rise) and will therefore limit the amount of buildable space. This seems negligent on behalf of our planning consultant to not have raised this issue in the planning process.

10. SA-G-3 Sea Level Rise Adaptation. Establish policies to minimize the risk to persons and property posed by potential sea level rise.

Please confirm what measures this General Plan establishes to minimize risk. These measures that affect basic life safety cannot be deferred under CEQA.

11. Chapter 3.9 of the DEIR discusses visual resources. As a licensed architect, I am considered as a professional expert in commenting on these issues. Visual Resources Figure 3.9-1 from the DEIR is copied below for reference.

Please note the area circled in red, the coastal view corridors identified in Sharp Park. As you are well aware, the current design for the new Sharp Park sea wall recently approved by the City Council as a hybrid option of hard armoring with sand nourishment will entail an approximately 5’ high sea wall above the existing road. Please clarify how this will protect these scenic resources which will no longer be able to be seen from the sidewalk or the surrounding roads by the majority of the population. ♦ Pacifica, CA 94044 ♦ Tel ♦
Without expensive and regular sand nourishment the city’s consultant, GHD, said the sea wall would need to be 8’ high. I believe GHD also said that even with these heights the proposed hard armoring will not protect the area from future projected storm surge and wave overtopping, so flooding will still be an issue. Please confirm. Is there additional drainage planned for the area? I’m anxiously waiting for Public Work’s drainage study due to be completed later this year.

12. Highway One is also identified on the map as a scenic route. I have seen no analysis or visual simulations in the DEIR that show how the views from Highway One may be impacted by the rezoning of tall structures in Sharp Park along Palmetto and Francisco. Please provide these simulations so that the impacts of the rezoning to Mixed Use Center can be properly evaluated.

13. The importance of Highway One View Corridors is also written in the DEIR on page 3.9.21.

As essential parts to Pacifica’s identity, I would expect to see a real analysis of visual impacts with simulations from multiple viewpoints. The increased height limits and new zoning right up next to the freeway at Manor Plaza should also be evaluated with visual simulations. This is the first view that most visitors get of Pacifica coming down the hill and is particularly important to the city’s image.

14. Furthermore, on page 3.9-22 somehow without any visual analysis, the impact on visual corridors has been declared to be less than significant. Please explain in detail how this conclusion was reached. ♦ Pacifica, CA 94044 ♦ Tel ♦

15. Page 3.9-5 of the DEIR states
There are no renderings provided in the Sharp Park Specific Plan of the relationship between these tall new buildings along Francisco and Palmetto to all the one- and two-story existing homes in the area.

Please provide this analysis and renderings so the visual impacts can be understood. I remember Mayor Mary Bier commenting at a Council Meeting when the renderings were presented that she would want to see those as well as they directly affect her constituents.

16. Page 3.9-6 of the DEIR states
♦ Pacifica, CA 94044 ♦ Tel ♦
Again these important view corridors may be lost due to both the sea wall and the more bulky and tall strucutres proposed under this General Plan Land Use Element. Can you confirm that this is in compliance with CEQA for Visual Resources, and with the Coastal Act, see pae 3.9-10 of the DEIR?

17. Would there not be some lost economic benefits in Sharp Park if the ocean, which is one of the major draws of the area, was no longer visible? Has this financial analyis been done as part of the GP update or sea wall project? I have not seen this information.

18. Under Impacts and Mitigation Measures on page 3.9-14 somehow, without this detailed visual analysis, it has been determined that impacts are less than significant. Please provide actual information to back up this statement to avoid a CEQA challenge.

19. Further down on page 3.9-14 it talks about landscape screeing as a method to protect visual resources.

I believe there are other General Plan and Municipal Code regulations that prohibit the use of landscaping to hide an otherwise unacceptable structure. I don’t have time to find references, but this was discussed in my letters regarding the Vista Mar Project. Landscaping obviously does nothing to help blocked ocean vistas from buildings so this line of argument is flawed. ♦ Pacifica, CA 94044 ♦ Tel ♦

20. There is one image in the DEIR on page 3.9-17 that shows ocean views being blocked by buildings even 35’ in height at the city’s property at 2212 Beach Boulevard. Does this indicate that at this site the height must even be reduced beyond current zoning limitations? Please clarify. Note that this image and the others after it in the DEIR, were taken from a higher elevation, not street level on Palmetto, so they should be redone.
♦ Pacifica, CA 94044 ♦ Tel ♦

21. Page 3.9-22
Doesn’t this mitigation measure contradict the basic concept in the Land Use Diagram to allow heights up to 55’ in this area. I am very confused.

22. The Coastal Commission also brought up their concerns about visual impacts of increased heights in their comment letter to the NOP sent on September 9, 2020. I have copied the letter here below. Please provide a response to their comments.

23. In this letter, the Coastal Commission also asked for a thorough geotechnical analysis of the area in this letter. I also asked for that information in a public hearing about the Sharp Park Specific Plan in 2021.

Do we know that the area’s soils and ground water table can even support a 55’ high building? Please add this analysis to the DEIR to ensure this proposed project even feasible. ♦ Pacifica, CA 94044 ♦ Tel ♦

24. From page 3.9-22 of the DEIR
This statement is in error. The Little Brown Church is visible from Highway One, as is the adjacent Salada lot. This is why the Pacifica Historical Society has chosen the Salada lot facing Francisco as the ideal location for the refurbished Ocean Shore Railroad Car. Please revise this section as required per actual analysis of what is visible from Highway One.

25. I also asked previously in my comment letter #4 whether NCCWD currently has the fire capacity to serve 5 story buildings in this area as they will require different equipment than needed for 3 story buildings. Please confirm. If new equipment is needed, please confirm the city has the financial resources to make these basic infrastructure improvements before this General Plan and Sharp Park Specific Plan are adopted.

26. I have not had a chance to review the Historical Preservation section of the GP or DEIR, but I would like to see some explanation of how these important resources are protected in the Sharp Park Specific Plan. Several sites along Palmetto that are being rezoned to Mixed Use Center currently house these vibrant buildings and gardens that are important to the community and that are well used, and that speak to our history as a town. Here are three for example. Wouldn’t the economic value added by increasing density to 5 stories entice developers to tear down these treasures that contribute to this unique and desirable shopping area now?

27. Traffic and Parking Exceptions
Many residents complain that parking is very difficult in this area now, especially on sunny days, which are more numerous now with climate change and reduction in coastal fog.

Page 3 ends

Pacifica City CouncilJune 25, 2022

Pacifica City Council
June 25, 2022