Contra Costa County, CA Animal Ordinances: Chickens & Livestock (2026)

Unincorporated Contra Costa County permits backyard chickens in residential zones subject to density, setback, and sanitation rules in the zoning and animal-control chapters. A common standard is up to 6 hens per residential parcel (larger parcels allow more), with coop and run setbacks of 20 to 40 feet from the nearest dwelling and at least 5 to 10 feet from property lines. Roosters are generally prohibited in suburban residential zones because of noise but allowed in agricultural zones (A-2 and above). Coops must be kept clean and predator-resistant; unsanitary conditions are a nuisance enforceable by Animal Services and Environmental Health. Slaughter of chickens on residential parcels is not allowed. Feed must be stored in rodent-proof containers — rat infestations from chicken feed are a leading source of complaints. East-county agricultural parcels (Byron, Knightsen, Bethel Island) allow commercial-scale poultry subject to county grading, wastewater, and air-quality rules. HOA-governed communities (Rossmoor, Blackhawk, Gale Ranch) often ban chickens even where county zoning permits them.