CA Sea Change Atlas
CA Sea Change Atlas
County Profiles Contra Costa County
Snapshot 2026-10-22 Data as of 2026-10-22

Sea level rise · Contra Costa County, CA

Sea level rise

Visualize sea level rise exposure with this snapshot. Consider incorporating this data into all community planning strategies. In many communities, rising sea levels are already increasing the impacts of high tide flooding and storm surge events.

Projections for the Port Chicago tide gauge, assigned to Contra Costa County · Exposure at 2, 4, 6, 8, 10 ft above MHHW

This is the 2026-10-22 snapshot. See the current profile.

In this profile

  1. People at Risk 01
  2. Flooded Facilities Can't Provide Critical Services 02
  3. Being Underwater Is Not a Good Business Plan 03
  4. Creating a Better Future: Yes, It Can Be Done 04
  5. When Is the Time to Act? Now! 05
  6. Digging Deeper 06
  7. About this data 07

People at Risk

Rising population numbers exacerbate potential flooding risk; impacts can be even greater when social vulnerability factors (age, income, capabilities) are involved, as these citizens may not be able to adequately prepare and respond.

View on map for People at Risk: opens the sea level rise layer and population density for Contra Costa County in a new tab

The map shows current data, not this snapshot's.

0.9%

(10,401 people) of Contra Costa County’s total population lives in areas exposed to just 2 ft of sea level rise. As is already the case in many parts of the country, these areas are the first to experience impacts.

Residents exposed at each increment of sea level rise.

Population: 2 ft 10,401, 4 ft 14,140, 6 ft 21,761, 8 ft 34,508, 10 ft 49,864. Aged 65 and over: 2 ft 1,983, 4 ft 2,503, 6 ft 3,467, 8 ft 5,350, 10 ft 7,922. Below the poverty line: 2 ft 1,403, 4 ft 1,731, 6 ft 2,418, 8 ft 3,580, 10 ft 5,140. 0 10k 20k 30k 40k 50k 10,401 Population 1,983 Aged 65 and over 1,403 Below the poverty line
Sea level rise
2 ft

Residents exposed at each increment of sea level rise: data table

Category2 ft4 ft6 ft8 ft10 ft
Population, ocean-connected1,6794,65713,06028,45247,586
Population, including low-lying areas10,40114,14021,76134,50849,864
Aged 65 and over, ocean-connected2731,0492,5264,6207,437
Aged 65 and over, including low-lying areas1,9832,5033,4675,3507,922
Below the poverty line, ocean-connected2099661,9723,3314,752
Below the poverty line, including low-lying areas1,4031,7312,4183,5805,140
Sources Census ACS 5-year estimates (2020–2024) (2024) Census 2020 tabulation blocks (TIGERweb) (2020) NOAA Sea Level Rise Viewer inundation extents (2026)

Flooded Facilities Can't Provide Critical Services

Fire and police stations. Hospitals. Shelters. These facilities play a central role in response and recovery. Understanding future exposure can help reduce damages and the conditions that make these services unavailable.

View on map for Flooded Facilities Can't Provide Critical Services: opens the sea level rise layer and critical facilities for Contra Costa County in a new tab

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0.5%

(2 of 415 facilities) of Contra Costa County’s critical facilities are in areas exposed to just 2 ft of sea level rise. These areas are the first to experience impacts.

Facilities exposed at each increment of sea level rise.

Schools (304 total): 2 ft 0 exposed (0 with low-lying areas), 4 ft 0 exposed (1 with low-lying areas), 6 ft 2 exposed (2 with low-lying areas), 8 ft 3 exposed (3 with low-lying areas), 10 ft 4 exposed (4 with low-lying areas). Police stations (28 total): 2 ft 0 exposed (0 with low-lying areas), 4 ft 0 exposed (0 with low-lying areas), 6 ft 0 exposed (0 with low-lying areas), 8 ft 1 exposed (1 with low-lying areas), 10 ft 1 exposed (1 with low-lying areas). Fire stations (77 total): 2 ft 1 exposed (2 with low-lying areas), 4 ft 1 exposed (2 with low-lying areas), 6 ft 2 exposed (3 with low-lying areas), 8 ft 4 exposed (5 with low-lying areas), 10 ft 6 exposed (6 with low-lying areas). Medical facilities (6 total): 2 ft 0 exposed (0 with low-lying areas), 4 ft 0 exposed (0 with low-lying areas), 6 ft 0 exposed (0 with low-lying areas), 8 ft 0 exposed (0 with low-lying areas), 10 ft 0 exposed (0 with low-lying areas). 0 100 200 300 0 0 2 0 Number of facilities of each type Schools Police stations Fire stations Medical facilities
Sea level rise
2 ft

Facilities exposed at each increment of sea level rise: data table

CategoryTotal2 ft exposed4 ft exposed6 ft exposed8 ft exposed10 ft exposed
Schools30400234
Schools, including low-lying areas30401234
Police stations2800011
Police stations, including low-lying areas2800011
Fire stations7711246
Fire stations, including low-lying areas7722356
Medical facilities600000
Medical facilities, including low-lying areas600000
Sources USGS National Structures Dataset (2026-03-18) NOAA Sea Level Rise Viewer inundation extents (2026)

Being Underwater Is Not a Good Business Plan

Flood-related losses of services, revenues, and salaries can hit a community hard.

View on map for Being Underwater Is Not a Good Business Plan: opens the sea level rise layer and jobs density for Contra Costa County in a new tab

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0.6%

(2,320 jobs) of Contra Costa County’s jobs are in areas exposed to just 2 ft of sea level rise.

Jobs in areas exposed at each increment of sea level rise.

2 ft: Ocean-connected 1,300 jobs, Additional, in low-lying areas 1,020 jobs. 4 ft: Ocean-connected 2,605 jobs, Additional, in low-lying areas 1,731 jobs. 6 ft: Ocean-connected 7,057 jobs, Additional, in low-lying areas 1,287 jobs. 8 ft: Ocean-connected 13,116 jobs, Additional, in low-lying areas 883 jobs. 10 ft: Ocean-connected 18,890 jobs, Additional, in low-lying areas 615 jobs. Total jobs 0 5k 10k 15k 2,320 4,336 8,344 13,999 19,505 2 ft 4 ft 6 ft 8 ft 10 ft

Jobs in areas exposed at each increment of sea level rise: data table

CategoryOcean-connectedAdditional, in low-lying areas
2 ft1,300 jobs1,020 jobs
4 ft2,605 jobs1,731 jobs
6 ft7,057 jobs1,287 jobs
8 ft13,116 jobs883 jobs
10 ft18,890 jobs615 jobs
Sources LEHD LODES8 workplace area characteristics (2023) Census 2020 tabulation blocks (TIGERweb) (2020) NOAA Sea Level Rise Viewer inundation extents (2026)

Creating a Better Future: Yes, It Can Be Done

Make it a goal: more natural areas (wetlands, forests, parks, dunes, etc.) to absorb floodwaters and protect the community, and less development in flood-prone areas. Consider not only today’s floodplain, but also the floodplain extent projected for the future.

View on map for Creating a Better Future: Yes, It Can Be Done: opens the sea level rise layer and natural areas for Contra Costa County in a new tab

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22.8%

(16.4 of 72 square miles) of the land inundated in Contra Costa County at 2 ft of sea level rise would be natural: wetland or upland.

Land cover inundated at each increment of sea level rise.

2 ft: Wetlands 14.3 sq mi, Upland 2.1 sq mi, Other 55.6 sq mi. 4 ft: Wetlands 16.5 sq mi, Upland 2.9 sq mi, Other 59.2 sq mi. 6 ft: Wetlands 17.1 sq mi, Upland 3.6 sq mi, Other 64.5 sq mi. 8 ft: Wetlands 17.4 sq mi, Upland 4.3 sq mi, Other 70.2 sq mi. 10 ft: Wetlands 17.5 sq mi, Upland 4.9 sq mi, Other 75.3 sq mi. % natural 0 20 40 60 80 22.8% 24.7% 24.3% 23.6% 22.9%Square miles inundated 2 ft 4 ft 6 ft 8 ft 10 ft

Land cover inundated at each increment of sea level rise: data table

CategoryWetlandsUplandOther
2 ft14.3 sq mi2.1 sq mi55.6 sq mi
4 ft16.5 sq mi2.9 sq mi59.2 sq mi
6 ft17.1 sq mi3.6 sq mi64.5 sq mi
8 ft17.4 sq mi4.3 sq mi70.2 sq mi
10 ft17.5 sq mi4.9 sq mi75.3 sq mi
Sources NOAA C-CAP regional land cover (1996–2021) NOAA Sea Level Rise Viewer inundation extents (2026)

When Is the Time to Act? Now!

Because a number of factors are involved, sea level rise projections are often expressed as scenarios. For projects involving structures with a long lifespan or where a loss would be catastrophic (power plants, ports, hospitals), the higher sea level rise scenarios should be considered. For projects with a shorter lifespan (bike paths, golf courses, parks), lower sea level rise scenarios may be appropriate.

Projections at the Port Chicago gauge, by scenario

Feet above 2000, by year

Projected sea level rise at the Port Chicago tide gauge, 2000 to 2150, by scenario Feet of sea level rise above 2000, for the Intermediate, Intermediate-High and High scenarios. The year each increment is reached is in the table. 2000 2020 2040 2060 2080 2100 2120 2140 4 ft 6 ft 8 ft 10 ft 2 ft Intermediate reaches 2 ft in 2083 Intermediate-High reaches 2 ft in 2067 High reaches 2 ft in 2060
Sea level rise
2 ft

2 ft is reached in:

Intermediate
2083
Intermediate-High
2067
High
2060

Feet above 2000, in 2050 and 2100

Projected sea level rise at the Port Chicago tide gauge in 2050 and 2100, by scenario Feet above 2000. 2050: Intermediate 0.8¤ ft, Intermediate-High 1.0 ft, High 1.3 ft. 2100: Intermediate 3.1 ft, Intermediate-High 4.8 ft, High 6.5 ft. 0 2 4 6 8 0.8¤ 1.0 1.3 2050 3.1 4.8 6.5 2100

¤ Under 1 ft, the lowest level the map shows.

Year each increment is reached

Sea level riseIntermediateIntermediate-HighHigh
2 ft208320672060
4 ft211320922079
6 ft215021152096
8 ftafter 215021482112
10 ftafter 2150after 21502131
Sources California Ocean Protection Council, State of California Sea Level Rise Guidance: 2024 Science & Policy Update, Appendix 2 (2024)

Digging Deeper

Go further with Contra Costa County's sea level rise in the atlas's other tools.

See Contra Costa County on the map

Opens the map on the county, highlighted, with the sea level rise layer switched on.

The map shows current data, not this snapshot's.

Compare the flood and sea level rise resources

Explore descriptions fo the different resources available, including those listed in the OPC guidance.

About this data

Data, methods and citation

Snapshot
2026-10-22 · all snapshots
Methodology
Version 1 · what changed
Tide gauge
Port Chicago (OPC 2024, Appendix 2)
Scenarios
Intermediate, Intermediate-High, High

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Recommended citation

California Sea Change Atlas. (2026, October 22). Contra Costa County coastal county profile: Sea level rise. https://seachangeatlas.org/county-profiles/county/contra-costa/2026-10-22/sea-level-rise/

SourcePeriod coveredRetrieved
Census ACS 5-year estimates (2020–2024)20242026-10-22
Census 2020 tabulation blocks (TIGERweb)20202026-10-22
NOAA Sea Level Rise Viewer inundation extents20262026-10-22
USGS National Structures Dataset2026-03-182026-10-22
LEHD LODES8 workplace area characteristics20232026-10-22
NOAA C-CAP regional land cover1996-01-01 to 2021-12-312026-10-22
California Ocean Protection Council, State of California Sea Level Rise Guidance: 2024 Science & Policy Update, Appendix 220242026-10-22