St. Clair County, IL

The USDA Economic Research Service Food Access Research Atlas flags 42 of St. Clair County's 64 census tracts as low-access, covering 134,558 residents of a 257K total population. That translates to a county-wide low food access share of 52.4%, 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 Illinois classifies tracts using the same distance thresholds the USDA applies nationwide, St. Clair 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 St. Clair County, 30,287 residents are flagged as low-income and more than one mile from a supermarket (the urban threshold), while 10,096 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 $68,915, a poverty rate of 13.8%, and SNAP participation covering 15,347 households — roughly 15.2% 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 7.3% of St. Clair 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 — 1.6% of the population — are counted separately because their food access patterns follow an institution rather than a household. With more than 30% of St. Clair County in a low-access area, the county sits well above the national median and warrants closer review of supermarket siting, SNAP outreach, and transit connections.