Contra Costa County, CA

The USDA Economic Research Service Food Access Research Atlas flags 72 of Contra Costa County's 291 census tracts as low-access, covering 231,367 residents of a 1.2M total population. That translates to a county-wide low food access share of 19.9%, which measures how many people live more than one mile from the nearest supermarket in urban settings or more than ten miles in rural settings. Because California classifies tracts using the same distance thresholds the USDA applies nationwide, Contra Costa County's figure is directly comparable to peer counties and to the state benchmark.

The food desert signal strengthens when distance is stacked with income. In Contra Costa County, 51,940 residents are flagged as low-income and more than one mile from a supermarket (the urban threshold), while 17,313 meet the low-income, ten-mile rural threshold. Those overlapping conditions are the precise combination the USDA uses to designate a food desert tract. Layered context includes a median household income of $120,020, a poverty rate of 8.3%, and SNAP participation covering 28,958 households — roughly 7.1% of the county — drawn from the Census Bureau American Community Survey five-year estimates.

Transportation is the hidden variable behind most food access gaps. About 5.1% of Contra Costa County households report no vehicle available, meaning any measured distance to a supermarket translates into a real trip on foot, by transit, or by asking for a ride. Group quarters residents — 1.0% of the population — are counted separately because their food access patterns follow an institution rather than a household. The county's low-access share sits near or below the typical U.S. county, but tract-level variation can still produce pockets of food desert conditions inside otherwise well-served areas.