13. Reso Adopting the 2024 City of Downey Hazard Mitigation Plan — Downey City Council, February 25, 2025 (part 2 of 2)

In terms of building construction types found in the region, wood frame construction makes up 86% of the building inventory.

The remaining percentage is distributed between the other general building types.

Critical Facility Inventory
Hazus breaks critical facilities into two (2) groups: essential facilities and high potential loss facilities (HPL). Essential facilities include hospitals, medical clinics, schools, fire stations, police stations and emergency operations facilities. High potential loss facilities include dams, levees, military installations, nuclear power plants and hazardous material sites.

For essential facilities, there are 4 hospitals in the region with a total bed capacity of 840 beds. There are 53 schools, 9 fire stations, 2 police stations and 2 emergency operation facilities. With respect to high potential loss facilities (HPL), there are no dams identified within the inventory. The inventory also includes no hazardous material sites, no military installations and no nuclear power plants.

Transportation and Utility Lifeline Inventory

Within Hazus, the lifeline inventory is divided between transportation and utility lifeline systems. There are seven (7) transportation systems that include highways, railways, light rail, bus, ports, ferry and airports. There are six (6) utility systems that include potable water, wastewater, natural gas, crude & refined oil, electric power and communications. The lifeline inventory data are provided in Tables 1 and 2.

The total value of the lifeline inventory is over 9,891.00 (millions of dollars). This inventory includes over 229.91 miles of highways, 78 bridges, 846.93 miles of pipes.

Building and Lifeline Inventory

City of Downey Hazard Mitigation Plan A-6
Table 1: Transportation System Lifeline Inventory

System

Component # Locations/
# Segments
Replacement value (millions of dollars)
Highway Bridges 78 781.9891
Segments 417 3011.8752
Tunnels 0 0.0000
Subtotal 3793.8643
Railways Bridges 14 79.6600
Facilities 2 5.3260
Segments 98 5051.3161
Tunnels 0 0.0000
Subtotal 5136.3021
Light Rail Bridges 0 0.0000
Facilities 2 11.4200
Segments 1 635.1414
Tunnels 0 0.0000
Subtotal 646.5614
Bus Facilities 0 0.0000
Subtotal 0.0000
Ferry Facilities 0 0.0000
Subtotal 0.0000
Port Facilities 0 0.0000
Subtotal 0.0000
Airport Facilities 0 0.0000
Runways 0 0.0000
Subtotal 0.0000
Total 9,576.70

City of Downey Hazard Mitigation Plan A-7
Table 2: Utility System Lifeline Inventory

System
Component # Locations /
Segments
Replacement value
(millions of dollars)
Potable Water Distribution Lines NA 16.5706
Facilities 1 39.2940
Pipelines 0 0.0000
Subtotal 55.8646
Waste Water Distribution Lines NA 9.9424
Facilities 0 0.0000
Pipelines 0 0.0000
Subtotal 9.9424
Natural Gas Distribution Lines NA 6.6283
Facilities 0 0.0000
Pipelines 1 134.5512
Subtotal 141.1795
Oil Systems Facilities 4 0.4720
Pipelines 0 0.0000
Subtotal 0.4720
Electrical Power Facilities 2 107.9334
Subtotal 107.9334
Communication Facilities 0 0.0000
Subtotal 0.0000
Total 315.40

City of Downey Hazard Mitigation Plan A-8

Hazus uses the following set of information to define the earthquake parameters used for the earthquake loss estimate provided in this report.

Scenario Name
Type of Earthquake
Fault Name
Historical Epicenter ID #

Probabilistic Return Period
Longitude of Epicenter
Latitude of Epicenter
Earthquake Magnitude
Depth (km)

Prob_mag5
Probabilistic
NA
NA
100.00
NA
NA

5.00 NA
Rupture Length (Km) NA

Rupture Orientation (degrees) NA
Attenuation Function NA
Earthquake Scenario

City of Downey Hazard Mitigation Plan A-9

Building Damage
Hazus estimates that about 5,108 buildings will be at least moderately damaged. This is over 11.00 % of the buildings in the region. There are an estimated 97 buildings that will be damaged beyond repair. The definition of the ‘damage states’ is provided in Volume 1: Chapter 5 of the Hazus technical manual. Table 3 below summarizes the expected damage by general occupancy for the buildings in the region. Table 4 below summarizes the expected damage by general building type.

Damage Categories by General Occupancy Type

12,000

10,000

8,000

6,000

4,000

2,000

0 Table 3: Expected Building Damage by Occupancy

None Slight Moderate Extensive Complete

Count

(%)

Count

(%)

Count

(%)

Count

(%)

Count

(%)
Agriculture 10.09 0.04 5.31 0.04 3.43 0.08 0.98 0.17 0.19 0.19 Commercial 1504.24 5.78 763.22 5.45 603.54 13.65 175.99 29.78 26.00 26.71 Education 44.95 0.17 20.66 0.15 12.02 0.27 3.01 0.51 0.36 0.37 Government 30.63 0.12 14.26 0.10 11.11 0.25 3.47 0.59 0.53 0.54 Industrial 635.48 2.44 326.05 2.33 298.37 6.75 95.10 16.09 15.01 15.42 Other Residential 4165.83 16.01 2252.60 16.08 850.71 19.25 176.89 29.93 24.97 25.65 Religion 84.03 0.32 40.93 0.29 27.60 0.62 8.16 1.38 1.27 1.31 Single Family 19552.65 75.12 10589.70 75.57 2613.30 59.12 127.33 21.55 29.02 29.81 Total 26,028 14,013 4,420 591 97
Direct Earthquake Damage
Complete
Extensive
Moderate
Slight

City of Downey Hazard Mitigation Plan A-10

Table 4: Expected Building Damage by Building Type (All Design Levels)

None Slight Moderate Extensive Complete
Count (%) Count (%) Count (%) Count (%) Count (%)
Wood 23117.90 88.82 12616.96 90.04 3125.92 70.72 149.11 25.23 36.23 37.21 Steel 573.82 2.20 305.59 2.18 324.30 7.34 97.87 16.56 14.09 14.47 Concrete 607.70 2.33 325.26 2.32 222.84 5.04 78.95 13.36 12.48 12.82 Precast 512.79 1.97 268.16 1.91 267.12 6.04 86.92 14.71 11.25 11.56 RM 1007.15 3.87 319.45 2.28 277.73 6.28 92.70 15.69 7.28 7.48 URM 163.78 0.63 106.06 0.76 89.97 2.04 30.37 5.14 9.19 9.44 MH 44.76 0.17 71.27 0.51 112.20 2.54 55.01 9.31 6.83 7.02 Total 26,028 14,013 4,420 591 97

*Note:

RM Reinforced Masonry
URM Unreinforced Masonry
MH Manufactured Housing

City of Downey Hazard Mitigation Plan A-11
Essential Facility Damage
Before the earthquake, the region had 840 hospital beds available for use. On the day of the earthquake, the model estimates that only 435 hospital beds (52.00%) are available for use by patients already in the hospital and those injured by the earthquake. After one week, 70.00% of the beds will be back in service. By 30 days, 90.00% will be operational.

Table 5: Expected Damage to Essential Facilities

Classification

Total
# Facilities
At Least Moderate
Damage > 50%
Complete
Damage > 50%

With Functionality
> 50% on day 1
Hospitals 4 1 0 3

Schools

53 30

0 23

EOCs

2 1

0 1

PoliceStations

2 0

0 2

Fire Stations

9 4

0 3

City of Downey Hazard Mitigation Plan A-12

Transportation Lifeline Damage

City of Downey Hazard Mitigation Plan A-13
Table 6: Expected Damage to the Transportation Systems

System

Component
Number of Locations
Locations/
Segments
With at Least
Mod. Damage
With Complete
Damage
With Functionality > 50 %
After Day 1 After Day 7

Highway

Segments

417

0 0

409

409
Bridges 78 0 0 78 78
Tunnels 0 0 0 0 0

Railways

Segments

98 0

0 98

98 Bridges 14 0 0 14 14
Tunnels 0 0 0 0 0
Facilities 2 0 0 2 2

Light Rail

Segments

1 0

0 1

1 Bridges 0 0 0 0 0
Tunnels 0 0 0 0 0
Facilities 2 0 0 2 2

Bus

Facilities

0 0

0 Ferry

Facilities

0 0

0 Port

Facilities

0 0

0 Airport

Facilities

0 0

0 Runways 0 0 0 0 0
Table 6 provides damage estimates for the transportation system.

Note: Roadway segments, railroad tracks and light rail tracks are assumed to be damaged by ground failure only. If ground failure maps are not provided, damage estimates to these components will not be computed.

Tables 7-9 provide information on the damage to the utility lifeline systems. Table 7 provides damage to the utility system facilities. Table 8 provides estimates on the number of leaks and breaks by the pipelines of the utility systems. For electric power and potable water, Hazus performs a simplified system performance analysis. Table 9 provides a summary of the system performance information.

City of Downey Hazard Mitigation Plan A-14
Table 7 : Expected Utility System Facility Damage

System

# of Locations
Total # With at Least
Moderate Damage
With Complete
Damage
with Functionality > 50 %

After Day 1

After Day 7
Potable Water 1 0 0 1 1
Waste Water 0 0 0 0 0
Natural Gas 0 0 0 0 0
Oil Systems 4 0 0 4 4
Electrical Power 2 2 0 0 2
Communication 0 0 0 0 0

Table 8 : Expected Utility System Pipeline Damage (Site Specific)

System Total Pipelines
Length (miles)
Number of
Leaks
Number of
Breaks
Potable Water 515 66 17
Waste Water 309 33 8
Natural Gas 24 1 0
Oil 0 0 0

Table 9: Expected Potable Water and Electric Power System Performance Total # of
Households
Number of Households without Service
At Day 1 At Day 3 At Day 7 At Day 30 At Day 90
Potable Water

Electric Power

55,350 0 0 0 0 0
0 0 0 0 0

City of Downey Hazard Mitigation Plan A-15

Induced Earthquake Damage

Fire Following Earthquake
Fires often occur after an earthquake. Because of the number of fires and the lack of water to fight the fires, they can often burn out of control. Hazus uses a Monte Carlo simulation model to estimate the number of ignitions and the amount of burnt area. For this scenario, the model estimates that there will be 2 ignitions that will burn about 0.03 sq. mi 0.12 % of the region’s total area.) The model also estimates that the fires will displace about 357 people and burn about 31 (millions of dollars) of building value.

Debris Generation

Hazus estimates the amount of debris that will be generated by the earthquake. The model breaks the debris into two general categories: a) Brick/Wood and b) Reinforced Concrete/Steel. This distinction is made because of the different types of material handling equipment required to handle the debris.

The model estimates that a total of 289,000 tons of debris will be generated. Of the total amount, Brick/Wood comprises

31.00% of the total, with the remainder being Reinforced Concrete/Steel. If the debris tonnage is converted to an estimated number of truckloads, it will require 11,560 truckloads (@25 tons/truck) to remove the debris generated by the earthquake.

Earthquake Debris (millions of tons)
0 0.0 0.1 0.1 0.2 0.2 0.2 0.3 0.3
Brick/ Wood Reinforced Concrete/Steel Total Debris Truck Load

0.09 0.20 0.29 11,560 (@25 tons/truck)

City of Downey Hazard Mitigation Plan A-16

Shelter Requirement
Hazus estimates the number of households that are expected to be displaced from their homes due to the earthquake and the number of displaced people that will require accommodations in temporary public shelters. The model estimates 562 households to be displaced due to the earthquake. Of these, 346 people (out of a total population of 187,417) will seek temporary shelter in public shelters.

Casualties

Hazus estimates the number of people that will be injured and killed by the earthquake. The casualties are broken down into four (4) severity levels that describe the extent of the injuries. The levels are described as follows;

· Severity Level 1: Injuries will require medical attention but hospitalization is not needed. · Severity Level 2: Injuries will require hospitalization but are not considered life-threatening · Severity Level 3: Injuries will require hospitalization and can become life threatening if not promptly treated.
· Severity Level 4: Victims are killed by the earthquake.

The casualty estimates are provided for three (3) times of day: 2:00 AM, 2:00 PM and 5:00 PM. These times represent the periods of the day that different sectors of the community are at their peak occupancy loads. The 2:00 AM estimate considers that the residential occupancy load is maximum, the 2:00 PM estimate considers that the educational, commercial and industrial sector loads are maximum and 5:00 PM represents peak commute time.

Table 10 provides a summary of the casualties estimated for this earthquake Social Impact
Displaced Households/ Persons Seeking Short Term Public Shelter 100 200 300 400 500 600
Displaced households
as a result of the
earthquake
562
Persons seeking
temporary public shelter
346

City of Downey Hazard Mitigation Plan A-17
Table 10: Casualty Estimates

Level 1

Level 2

Level 3

Level 4
2 AM Commercial 2.00 0.39 0.05 0.10

2 PM
Commuting 0.01 0.01 0.01 0.00
Educational 0.00 0.00 0.00 0.00
Hotels 0.03 0.00 0.00 0.00
Industrial 3.32 0.66 0.08 0.16
Other-Residential 58.02 9.49 0.99 1.92
Single Family 55.38 5.23 0.15 0.25
Total

Commercial
119

130.31
16 25.59
1 3.24
2 6.32

5 PM
Commuting 0.06 0.07 0.12 0.02
Educational 53.66 10.25 1.29 2.51
Hotels 0.00 0.00 0.00 0.00
Industrial 24.42 4.87 0.61 1.19
Other-Residential 15.87 2.64 0.29 0.53
Single Family 15.03 1.46 0.05 0.07
Total

Commercial
239

93.11 45

18.32 6

2.34 11

4.49 Commuting 1.18 1.44 2.60 0.49
Educational 0.44 0.08 0.01 0.02
Hotels 0.01 0.00 0.00 0.00
Industrial 15.26 3.04 0.38 0.75
Other-Residential 22.08 3.67 0.40 0.74
Single Family 20.87 2.03 0.07 0.10
Total 153 29 6 7

City of Downey Hazard Mitigation Plan A-18
Economic Loss
The total economic loss estimated for the earthquake is 1,927.99 (millions of dollars), which includes building and lifeline related losses based on the region's available inventory. The following three sections provide more detailed information about these losses.

City of Downey Hazard Mitigation Plan A-19
Building-Related Losses

The building losses are broken into two categories: direct building losses and business interruption losses. The direct building losses are the estimated costs to repair or replace the damage caused to the building and its contents. The business interruption losses are the losses associated with inability to operate a business because of the damage sustained during the earthquake. Business interruption losses also include the temporary living expenses for those people displaced from their homes because of the earthquake.

The total building-related losses were 1,875.34 (millions of dollars); 17 % of the estimated losses were related to the business interruption of the region. By far, the largest loss was sustained by the residential occupancies which made up over 28 % of the total loss. Table 11 below provides a summary of the losses associated with the building damage.

800

700

600

500

400

300

200

100

0 Table 11: Building-Related Economic Loss Estimates
(Millions of dollars)

Category

Area

Single
Family

Other
Residential

Commercial

Industrial

Others

Total
Income Losses
Wage 0.0000 4.4912 71.4254 5.5569 3.8617 85.3352
Capital-Related 0.0000 1.9113 58.3421 3.6757 1.0965 65.0256 Rental 5.0331 11.1100 34.6079 3.2166 1.7909 55.7585
Relocation 17.9741 7.7059 56.2170 15.8173 16.7360 114.4503 Subtotal 23.0072 25.2184 220.5924 28.2665 23.4851 320.5696 Capital Stock Losses
Structural 38.4515 19.4306 106.3340 52.2232 21.5047 237.9440 Nonstructural 203.3306 130.7224 290.4254 170.8951 80.9846 876.3581 Content 62.2401 32.0431 142.3619 118.4188 36.8291 391.8930 Inventory 0.0000 0.0000 31.2146 17.2064 0.1494 48.5704
Subtotal 304.0222 182.1961 570.3359 358.7435 139.4678 1554.7655 Total 327.03 207.41 790.93 387.01 162.95 1875.34

Single
Family
Other
Residential
Commercial
Industrial
Others

Earthquake Losses by Loss Type ($ millions) Earthquake Losses by Occupancy Type ($ millions)

City of Downey Hazard Mitigation Plan A-20
Transportation and Utility Lifeline Losses
For the transportation and utility lifeline systems, Hazus computes the direct repair cost for each component only. There are no losses computed by Hazus for business interruption due to lifeline outages. Tables 12 & 13 provide a detailed breakdown in the expected lifeline losses.

Table 12: Transportation System Economic Losses
(Millions of dollars)

System Component Inventory Value Economic Loss Loss Ratio (%) Highway Segments 3011.8752 0.0000 0.00
Bridges 781.9891 10.6380 1.36
Tunnels 0.0000 0.0000 0.00
Subtotal 3793.8643 10.6380
Railways Segments 5051.3161 0.0000 0.00
Bridges 79.6600 0.3756 0.47
Tunnels 0.0000 0.0000 0.00
Facilities 5.3260 0.9034 16.96
Subtotal 5136.3021 1.2790
Light Rail Segments 635.1414 0.0000 0.00
Bridges 0.0000 0.0000 0.00
Tunnels 0.0000 0.0000 0.00
Facilities 11.4200 1.9181 16.80
Subtotal 646.5614 1.9181
Bus Facilities 0.0000 0.0000 0.00
Subtotal 0.0000 0.0000
Ferry Facilities 0.0000 0.0000 0.00
Subtotal 0.0000 0.0000
Port Facilities 0.0000 0.0000 0.00
Subtotal 0.0000 0.0000
Airport Facilities 0.0000 0.0000 0.00
Runways 0.0000 0.0000 0.00
Subtotal 0.0000 0.0000
Total 9,576.73 13.84

City of Downey Hazard Mitigation Plan A-21
Table 13: Utility System Economic Losses
(Millions of dollars)

System Component Inventory Value Economic Loss Loss Ratio (%) Potable Water Pipelines 0.0000 0.0000 0.00
Facilities 39.2940 3.7703 9.60
Distribution Lines 16.5706 0.2983 1.80
Subtotal 55.8646 4.0686
Waste Water Pipelines 0.0000 0.0000 0.00
Facilities 0.0000 0.0000 0.00
Distribution Lines 9.9424 0.1499 1.51
Subtotal 9.9424 0.1499
Natural Gas Pipelines 134.5512 0.0000 0.00
Facilities 0.0000 0.0000 0.00
Distribution Lines 6.6283 0.0513 0.77
Subtotal 141.1795 0.0513
Oil Systems Pipelines 0.0000 0.0000 0.00
Facilities 0.4720 0.0445 9.43
Subtotal 0.4720 0.0445
Electrical Power Facilities 107.9334 34.5019 31.97
Subtotal 107.9334 34.5019
Communication Facilities 0.0000 0.0000 0.00
Subtotal 0.0000 0.0000
Total 315.39 38.82

City of Downey Hazard Mitigation Plan A-22
County Listing for the Region
Los Angeles, CA

Regional Population and Building Value Data

State

County Name

Population
Building Value (millions of dollars)
Residential Non-Residential Total
California
Los Angeles

187,417

14,063

15,450

29,513
Total Region 187,417 14,063 15,450 29,513

City of Downey Hazard Mitigation Plan A-23

Flood Analysis
100-Year Flood

Disclaimer:

Totals only reflect data for those census tracts/blocks included in the user's study region.

The estimates of social and economic impacts contained in this report were produced using Hazus loss estimation methodology software which is based on current scientific and engineering knowledge. There are uncertainties inherent in any loss estimation technique. Therefore, there may be significant differences between the modeled results contained in this report and the actual social and economic losses following a specific Flood. These results can be improved by using enhanced inventory data and flood hazard information.

Hazus: Flood Global Risk Report
Region Name: Downey, CA
Flood Scenario: Full
Print Date: Wednesday, March 29, 2023

City of Downey Hazard Mitigation Plan A-24

Table of Contents
Section
General Description of the Region
Building Inventory
General Building Stock
Essential Facility Inventory
Flood Scenario Parameters
Building Damage
General Building Stock
Essential Facilities Damage
Induced Flood Damage
Debris Generation
Social Impact
Shelter Requirements
Economic Loss
Building-Related Losses
County Listing for the Region
Regional Population and Building Value Data

City of Downey Hazard Mitigation Plan A-25

General Description of the Region

Hazus is a regional multi-hazard loss estimation model that was developed by the Federal Emergency Management Agency (FEMA) and the National Institute of Building Sciences (NIBS). The primary purpose of Hazus is to provide a methodology and software application to develop multi -hazard losses at a regional scale. These loss estimates would be used primarily by local, state and regional officials to plan and stimulate efforts to reduce risks from multi- hazards and to prepare for emergency response and recovery.

The flood loss estimates provided in this report were based on a region that included 1 county(ies) from the following state(s):

- California

Note:

Appendix A contains a complete listing of the counties contained in the region .

The geographical size of the region is approximately 18 square miles and contains 1,606 census blocks. The region contains over 55 thousand households and has a total population of 187,241 people. The distribution of population by State and County for the study region is provided in Appendix B .

There are an estimated 45,149 buildings in the region with a total building replacement value (excluding contents) of 29,511 million dollars. Approximately 89.44% of the buildings (and 47.65% of the building value) are associated with residential housing.

City of Downey Hazard Mitigation Plan A-26
Building Exposure by Occupancy Type for the Study Region ($1000's)

Building Inventory

General Building Stock

Hazus estimates that there are 45,149 buildings in the region which have an aggregate total replacement value of 29,511 million dollars. Table 1 and Table 2 present the relative distribution of the value with respect to the general occupancies by Study Region and Scenario respectively. Appendix B provides a general distribution of the building value by State and County.

Table 1
Building Exposure by Occupancy Type for the Study Region

Occupancy Exposure ($1000) Percent of Total
Residential 14,062,053 47.6%
Commercial 8,325,499 28.2%
Industrial 4,696,362 15.9%
Agricultural 9,651 0.0%
Religion 421,210 1.4%
Government 235,576 0.8%
Education 1,760,873 6.0%
Total 29,511,224 100%

Residential $14,062,053
Commercial $8,325,499
Industrial $4,696,362
Agricultural $9,651
Religion $421,210
Government $235,576
Education $1,760,873
Total: $29,511,224

City of Downey Hazard Mitigation Plan A-27

Table 2
Building Exposure by Occupancy Type for the Scenario

Occupancy Exposure ($1000) Percent of Total
Residential 4,158,336 35.1%
Commercial 3,756,901 31.7%
Industrial 2,718,829 22.9%
Agricultural 7,800 0.1%
Religion 195,444 1.6%
Government 165,958 1.4%
Education 856,972 7.2%
Total 11,860,240 100%

Essential Facility Inventory

For essential facilities, there are 4 hospitals in the region with a total bed capacity of 840 beds.

There are 53 schools, 9 fire stations, 2 police stations and 2 emergency operation centers.

Building Exposure by Occupancy Type for the Scenario ($1000's)

City of Downey Hazard Mitigation Plan A-28

Hazus used the following set of information to define the flood parameters for the flood loss estimate provided in this report.

Study Region Name: Downey, CA
Scenario Name:

Return Period Analyzed:

Analysis Options Analyzed:

Full
100
No What-Ifs

Study Region Overview Map

Illustrating scenario flood extent, as well as exposed essential facilities and total exposure

Flood Scenario Parameters

City of Downey Hazard Mitigation Plan A-29

Building Damage

General Building Stock Damage

Hazus estimates that about 804 buildings will be at least moderately damaged. This is over 67% of the total number of buildings in the scenario. There are an estimated 3 buildings that will be completely destroyed. The definition of the ‘damage states’ is provided in the Hazus Flood Technical Manual. Table 3 below summarizes the expected damage by general occupancy for the buildings in the region. Table 4 summarizes the expected damage by general building type.

Total Economic Loss (1 dot = $300K) Overview Map

City of Downey Hazard Mitigation Plan A-30

Table 3: Expected Building Damage by Occupancy

1-10 11-20 21-30 31-40 41-50 >50
Occupancy Count (%) Count (%) Count (%) Count (%) Count (%) Count (%) Agriculture
0 0

0 0

0 0
Commercial 43 80 11 20 0 0 0 0 0 0 0 0
Education 0 0 0 0 0 0 0 0 0 0 0 0
Government 0 0 0 0 0 0 0 0 0 0 0 0
Industrial 40 60 24 36 3 4 0 0 0 0 0 0
Religion 0 0 0 0 0 0 0 0 0 0 0 0
Residential 555 42 564 43 142 11 53 4 4 0 3 0

Total

638
599
145
53 4
3 Counts By Damage Level

Dam age Level 1-10 638
Dam age Level 11-20 599
Dam age Level 21-30 145
Dam age Level 31-40 53
Dam age Level 41-50 4
Dam age Level >50 3
Total: 1442

City of Downey Hazard Mitigation Plan A-31

Table 4: Expected Building Damage by Building Type

Building 1-10 11-20 21-30 31-40 41-50 >50
Type Count (%) Count (%) Count (%) Count (%) Count (%) Count (%)

Concrete 35 69 15 29 1 2 0 0 0 0 0 0
Manu Housing 0 0 3 75 1 25 0 0 0 0 0 0
Masonry 15 60 10 40 0 0 0 0 0 0 0 0
Steel 18 58 11 35 2 6 0 0 0 0 0 0
Wood 557 42 554 42 141 11 53 4 4 0 3 0

City of Downey Hazard Mitigation Plan A-32
Essential Facility Damage

Before the flood analyzed in this scenario, the region had 840 hospital beds available for use. On the day of the scenario flood event, the model estimates that 840 hospital beds are available in the region.

Table 5: Expected Damage to Essential Facilities

# Facilities

Classification

Total
At Least
Moderate
At Least
Substantial L

ss of Use

Emergency Operation Centers 2 0 0 0
Fire Stations 9 0 0 0
Hospitals 4 0 0 0
Police Stations 2 0 0 0
Schools 53 0 0 0

If this report displays all zeros or is blank, two possibilities can explain this. (1) None of your facilities were flooded. This can be checked by mapping the inventory data on the depth grid. (2) The analysis was not run. This can be tested by checking the run box on the Analysis Menu and seeing if a message box asks you to replace the existing results.

City of Downey Hazard Mitigation Plan A-33
Debris Breakdown (tons)

1000 2000 3000 4000 5000 6000
Total Debris
Finishes
Structure
Foundation

Induced Flood Damage

Debris Generation

Hazus estimates the amount of debris that will be generated by the flood. The model breaks debris into three general categories: 1) Finishes (dry wall, insulation, etc.), 2) Structural (wood, brick, etc.) and 3) Foundations (concrete slab, concrete block, rebar, etc.). This distinction is made because of the different types of material handling equipment required to handle the debris.

5,893

5,263

35 96

The model estimates that a total of 5,893 tons of debris will be generated. Of the total amount, Finishes comprises 89% of the total, Structure comprises 6% of the total, and Foundation comprises 5%. If the debris tonnage is converted into an estimated number of truckloads, it will require 236 truckloads (@25 tons/truck) to remove the debris generated by the flood.

City of Downey Hazard Mitigation Plan A-34

Shelter Requirements

Hazus estimates the number of households that are expected to be displaced from their homes due to the flood and the associated potential evacuation. Hazus also estimates those displaced people that will require accommodations in temporary public shelters. The model estimates 3,126 households (or 9,378 of people) will be displaced due to the flood. Displacement includes households evacuated from within or very near to the inundated area. Of these, 621 people (out of a total population of 187,241) will seek temporary shelter in public shelters.

Social Impact
Displaced Population/Persons Seeking Short Term Public Shelter 621
9,378
2000 4000 6000 8000 10000
Persons Seeking
Shelter
Displaced Population

City of Downey Hazard Mitigation Plan A-35

Economic Loss

The total economic loss estimated for the flood is 1,209.09 million dollars, which represents 10.19 % of the total replacement value of the scenario buildings.

Building-Related Losses

The building losses are broken into two categories: direct building losses and business interruption losses. The direct building losses are the estimated costs to repair or replace the damage caused to the building and its contents. The business interruption losses are the losses associated with inability to operate a business because of the damage sustained during the flood. Business interruption losses also include the temporary living expenses for those people displaced from their homes because of the flood.

The total building-related losses were 568.77 million dollars. 53% of the estimated losses were related to the business interruption of the region. The residential occupancies made up 11 .54% of the total loss. Table 6 below provides a summary of the losses associated with the building damage.

City of Downey Hazard Mitigation Plan A-36

Table 6: Building-Related Economic Loss Estimates
(Millions of dollars)

Category

Building Loss
Area Residential Commercial Industrial Others Total
Building 350.79 229.99 260.33 38.33 879.44
Content 202.84 680.27 679.61 237.94 1,800.66
Inventory 0.00 150.63 90.64 0.65 241.92
Subtotal 553.63 1,060.88 1,030.58 276.93 2,922.01
Business Interruption
Income 5.48 473.99 24.96 96.84 601.26
Relocation 104.88 172.73 29.20 61.69 368.49
Rental Income 54.50 126.22 7.42 9.14 197.29
Wage 12.88 502.95 32.92 547.10 1,095.85
Subtotal 177.74 1,275.88 94.50 714.78 2,262.89
ALL Total 731.36 2,336.76 1,125.08 991.70 5,184.91

Losses by Occupancy Types ($M)

City of Downey Hazard Mitigation Plan A-52

County Listing for the Region

California
- Los Angeles

Regional Population and Building Value Data

Building Value (thousands of dollars)

Population

Residential

Non-Residential

Total

California
Los Angeles 187,241 14,062,053 15,449,171 29,511,224
Total 187,241 14,062,053 15,449,171 29,511,224
Total Study Region 187,241 14,062,053 15,449,171 29,511,224

City of Downey Hazard Mitigation Plan B-1

Stakeholder Engagement

Table of Contents
B.1 Stakeholder Engagement ................................................................................... 2 B.2 Public Engagement ............................................................................................ 6 B.3 Steering Committee Meetings.......................................................................... 17 B.4 Workshops ........................................................................................................ 21 B.5 Public Comment Period ................................................................................... 23 B.6 Public Survey .................................................................................................... 25

List of Tables
Table B.1: Support Organizations invited to participate ................................................... 2 Table B.2: Community Stakeholder Webinar – Attendee Report ..................................... 5 Table B.3: Survey Totals ............................................................................................... 26

City of Downey Hazard Mitigation Plan B-2

B.1 Stakeholder Engagement
The City of Downey engaged with various stakeholders from supporting organizations on multiple occasions, including the steering committee during meetings and workshops.

These partners were given the opportunity to provide feedback via email on the plan during the commend period to ensure equitable opportunity. The whole community partners assisted in identifying hazards, assessing risks and vulnerability, record critical facilities, and develop and prioritize mitigation actions. In addition, stakeholders were given an opportunity to review the draft of the plan. The City understands the importance of stakeholder engagement and that their contribution strengthens the content and outcomes of the mitigation plan. Various organizations mentioned below are also members of the Steering Committee.

Table B.1: Support Organizations invited to participate Organization Type of
Organization
Invited to
Participate
Attended a Hazard
Mitigation Meeting or
Webinar
American Red Cross
Nonprofit/
Community
Organization
Yes Yes
Area E Disaster
Management Area
Coordinator
Government Yes Yes
Assistance League of
Downey
Community
Organization/
Underserved
Yes -
Boy Scouts of America,
Troop 2
Nonprofit/
Community
Organization
Yes Yes
Chamber of Commerce Represents
Private Sector Yes Yes
Clergy Council Religious Yes -
City of Norwalk Government Yes Yes
City of Paramount Government Yes Yes
Downey Adult School Academic Yes -
Downey Amateur Radio
Club
Community
Organization Yes Yes
Downey Cemetery District Community
Organization Yes Yes
Downey CERT Community
Organization Yes Yes
Downey Coordinating
Council
Community
Organization Yes -

City of Downey Hazard Mitigation Plan B-3

Downey Food Helps
Community
Organization/
Underserved
Yes -
Downey Unified School
District Academic Yes Yes
Gangs Out of Downey
(G.O.O.D.)
Community
Organization/
Underserved
Yes -
Kaiser- Downey Healthcare
Sector Yes Yes
LA County Public Health
Government,
Healthcare
Sector
Yes -
Los Angeles County Office
of Education Academic Yes Yes
PIH Health Hospital -
Downey
Healthcare
Sector Yes Yes
PTA HELPS Academic,
Underserved Yes Yes
Rancho Los Amigos
National Rehabilitation
Center
Healthcare
Sector Yes Yes
Rotary Club of Downey Represents
Private Sector Yes Yes
Southeast Area Animal
Control Authority (SEACCA) Government Yes Yes
SoCal Gas Private Sector Yes Yes
The Arc Los Angeles and
Orange Co.

Community
Organization/
Underserved
Yes Yes
The Whole Child
Community
Organization/
Underserved
Yes -
TLC Family Resource
Center
Academic/
Underserved Yes -
B.1.1 Stakeholder Meetings
Downey Resilience Council
On September 12, 2024, the Downey Resilience Council participated in a draft review meeting for the hazard mitigation plan. A draft of the plan was presented, and members of the council were given an opportunity to provide feedback and recommended changes to the plan.

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Figure B.1: Downey Resilience Council Meeting Sign-in Sheet

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Community Stakeholder Webinar
A City of Downey Hazard Mitigation Plan Community Stakeholder Webinar was conducted on September 19, 2024. The webinar was for key community stakeholders to provide input into the planning process, review key elements of the draft plan, and to invite them to be part of the annual maintenance process in subsequent years.

Table B.2: Community Stakeholder Webinar – Attendee Report GoToWebinar Attendee Report: City of Downey Hazard Mitigation Plan Community Stakeholder Webinar – September 19, 2024
Last Name First Name Organization Job Title
Calvert Michael • Downey Chamber of Commerce Executive Director Duren Shantae • City of Downey Management Analyst
Guzman Stephen
• The P.C. Help Desk
• ARC of L.A. O.C.
• Downey A.C.E.R.T.

Owner - President
Khlok Rakdy • City of Downey Emergency Manager

City of Downey Hazard Mitigation Plan B-6

Abe Daiko • ISC Consultant
Heyman Brian • Downey Cemetery District Vice Chair, Board of Trustees
Hutchinson Thomas • Rotary Club of Downey
• BSA Scouting Troop 2
President Elect and
Scoutmaster
Medina Roxana • PTA HELPS Director

B.2 Public Engagement

B.2.1 Public Meetings for Plan Development
The City utilized two existing emergency preparedness events to host public meetings to review updates to the Hazard Mitigation Plan. The public meeting presentation was developed to guide the discussion for the two public meetings. The meetings took place on: May 16, 2023, and May 22, 2023.

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Figure B.2: Touch-Truck Public Event

B.2.2 Public Meeting for Draft Review
A major public event was held on July 24, 2024, to promote the hazard mitigation plan and invite residents to provide feedback. The July 24, 2024, public event was held in conjunction with the City of Downey’s Concert Under the Stars. The City had a booth at the event and was available to discuss the plan, talk about emergency preparedness and mitigation, and was available to discuss how residents could be more resilient to the various hazards that could affect the City. The City announced to the 1,700 residents that attended the concert to learn about hazard mitigation and to visit the booth to review the plan. The July 24th concert (Las Catrinas-Mariachi) was selected to specifically reach out to the Hispanic population in the City, which is a predominant and important population segment in the City. Historically, this has been a group that has underutilized emergency preparedness resources, may have language gaps, and is hard to reach group…. an important underrepresented demographic for the community. The concert also offered residents age 65 and over or with a disability to request a ride to the concert. City staff were on-hand to provide Spanish translation. Approximately 1,700 residents attended the event. Over 100 residents engaged with staff at the booth.

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Figure B.3: Concert Under the Stars Series Promotion

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Figure B.4: Public Event Promotion – Plan Review

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Figure B.5: Announcement Inviting Residents to Visit the Booth to Learn About Hazard Mitigation and Review the Plan

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Figure B.6: Ride Service for Elderly and Those With a Disability

Figure B.7: Public Event Attendance

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Figure B.8: Public Event Draft Plan and Forms

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Figure B.9: Public Event Sign-in Sheets

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B.3 Steering Committee Meetings
A total of approximately 32 steering committee members were part of the HMP update process. See Chapter 1, Section 1.2.2, Table 1.1 for a complete list of members organized by organization, name, and title of position.

B.3.1 Kick Off Steering Committee Meeting
The Kickoff Meeting for the City was conducted on March 15, 2023, and used an agenda to guide the meeting’s discussion. The Kickoff Meeting acted as the first Steering Committee Meeting. Please see the agenda and sign in sheets of the steering committee meeting below.

City of Downey Hazard Mitigation Plan B-18

B.3.2 Kick Off Steering Committee #1 Sign In Sheets

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B.3.3 Steering Committee Meeting #2
The second Steering Committee Meeting for the City occurred virtually via Microsoft Teams on April 26, 2023, and used an agenda to guide the meeting’s discussion. Please see the agenda and sign in sheets of the steering committee meeting below.

B.3.4 Steering Committee Meeting #2 Sign In Sheets

City of Downey Hazard Mitigation Plan B-20

City of Downey Hazard Mitigation Plan B-21

B.4 Workshops
One steering committee workshop was conducted to identify and update hazards and develop new mitigation strategies. See sign in sheets and photos of the workshop below.

B.4.1 Workshop Sign In Sheets

City of Downey Hazard Mitigation Plan B-22

B.4.2 Workshop Photos

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B.5 Public Comment Period
The City of Downey Office of Emergency Management sought public input on the Hazard Mitigation Plan. The City invited partners and public stakeholders to provide input during the comment review period before the Plan was submitted to Cal OES and FEMA for review. The comment period consisted of 2 weeks (October 3 – October 17, 2023) for feedback. Another opportunity for the public to review the draft of the plan was made available again from July 15, 2024, to September 15, 2024. The second public comment and review period coincided with a major public event on July 24, 2024, to promote the hazard mitigation plan and invite residents to provide feedback.

B.5.1 Social Media
The public comment period was advertised via multiple social media platforms.

Screengrabs of the social media advertisement can be seen below via the City website and Instagram. The social media post on Instagram was published a total of three times during the initial 2-week period.

Figure B.10: Social Media – Public Comment

City of Downey Hazard Mitigation Plan B-24

City of Downey Hazard Mitigation Plan B-25

B.6 Public Survey
A disaster preparedness and mitigation survey was developed to gauge household preparedness, perception of risk, and the perceived need to mitigate certain hazards. The questionnaire was made available online. The survey results guided the steering committee with prioritizing hazard impacts and validating goals, objectives, and mitigation strategies, and ensured the Plan adequately addressed the public's concerns and priorities.

The survey was distributed through a variety of methods beginning on February 24, 2023, and was closed on March 28, 2023. The questionnaire was dispersed via e-mail blasts, social media platforms (Facebook and Instagram), and the City main web page.

Ultimately, respondents were selected from among those who volunteered to participate.

No special weighing was done to reflect the demographic composition of the City.

The questionnaire used a combination of descriptive and exploratory questions to gain an understanding of general preparedness intentions and behavior, as well as personal and demographic factors influencing decision making. These questions further consisted of select categories, these categories include:
• general preparedness
• emergency information sources
• hazard risk perception
• hazard mitigation priorities
• disaster experience
• evacuation
• functional and access needs
• demographics
The questionnaire amounted to 32 questions of multiple choice and open-ended questions. In total, 105 respondents participated in the survey. To ensure all data could be accurately correlated, only the 54 completed questionnaires were used in this report (please reference the first row in the table below). 51 respondents were disqualified for partial completion and never actually submitted the survey. Completed surveys included those responses where the respondent started and reached the end of the survey. In some

City of Downey Hazard Mitigation Plan B-26

situations, the respondent chose not to answer one or more questions which is why some discrepancies exist in the total number of responses per question.

Table B.3: Survey Totals
Survey Totals
Survey Status Total
Completed 54
Partial 51
Total 105

B.6.1 Social Media
The public comment period was advertised via
multiple social media platforms. Screengrabs of
the social media advertisement can be seen
below via Facebook and Instagram. The social
media posts were published three times via each
platform.

City of Downey Hazard Mitigation Plan B-27

B.6.2 Survey Results
Screengrabs of the questions and their corresponding results are outlined below.

1. Approximately how many years have you lived or worked (if you are not a resident) in Downey?

2. What fire station is closest to your residence or place of business (if you are not a resident)?

City of Downey Hazard Mitigation Plan B-28

3. Do you have home internet access?

4. Please indicate those activities you have done to prepare for emergencies and disasters.

Please select ALL that apply. I have…

5. Have any of the reasons below prevented you from pursuing additional preparedness activities? Please select ALL that apply.

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6. If you have an emergency supply kit, what items do you have in your kit? Please select ALL that apply.

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7. Please indicate where you go to obtain emergency and disaster related information? Please select ALL that apply.

8. Would you agree or disagree with the following statements?

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9. Please indicate how the City of Downey can better assist you in preparing for emergencies and disasters (example: provide preparedness materials in my language).

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10. If a disaster (i.e. earthquake) impacted Downey, knocking out electricity and running water, would your household be able to manage on its own for at least three (3) days?

11. Which of the following may prevent you from recovering from a disaster? Please select ALL that apply.

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12. Do you believe that your household and/or place of business might ever be threatened by the following hazards? Please rate what hazards present the greatest risk. Low Risk = Low impact on threat to life and property damage. Medium Risk = Medium impact on threat to life and property damage. High Risk = High impact on threat to life and property damage

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13. Please select the answer that best describes your experience.

14. If you have experienced any damage(s) or injury(ies) from a disaster, please list the hazard(s) that caused the damages/losses and/or injuries (Example: flooding, wind, winter storm)

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15. If you have experienced any damage(s) or injury(ies) from a disaster, please indicate where this occurred (Example: my home, on a roadway or intersection, at work, on vacation, etc.)

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16. If you have experienced any damage(s) or injury(ies) from a disaster, please describe the damages and/or injuries. (Example: basement flooded, roof was damaged, vehicle was damaged, broken bones, lacerations, etc.)

17. Please select the best answer. The risks associated with the City of Downey's most prevalent hazards are:

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18. Based on YOUR PERCEPTION of the City's hazards, to what degree of emphasis would you expect the City to mitigate the following hazards? Mitigation definition: Hazard mitigation is any sustainable action that reduces or eliminates long-term risk to people and property from future disasters. Hazard mitigation includes long-term solutions that reduce the impact of disasters in the future.

19. If an evacuation was ordered for your area, please indicate how likely you would be to do the following.

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20. What might prevent you from leaving your place of residence if there was an evacuation order? Please select ALL that apply.

21. If you were to evacuate, where would you most likely stay? Please select the best answer.

22. In an evacuation, would you or anyone in your household require special assistance?

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23. If yes, would that assistance be provided by someone within your household, by an outside agency, or by a friend or relative outside your household?

24. What type of structure do you live in?

25. Which of the following best describes your race/ethnicity? Please select ALL that apply.

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26. Please indicate the primary language(s) spoken in your household.

27. Please indicate your gender identity.

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28. What is your employment status? (Click all that apply.)

29. What is your household annual income?

30. (OPTIONAL): If you would like to learn how to better prepare yourself for emergencies, the city offers the Community Emergency Response Training (CERT) two times a year.

Please provide your contact information below and we will provide you with the information.

Resident contact information is not provided in this document due to privacy. Respondent answers are available via the Office of Emergency Management.

31. (OPTIONAL): If you have any additional comments, questions, or feedback, please use the space below to provide your comment.

City of Downey Hazard Mitigation Plan C-1

Resolution Documentation

Table of Contents
C.1 Resolution Placeholder ...................................................................................... 2

City of Downey Hazard Mitigation Plan C-2

C.1 Resolution Placeholder

Downey City CouncilFebruary 25, 2025

Downey City Council
February 25, 2025