Los Angeles County, one of California's original 27 counties, was established on Feb. 18, 1850. It is one of the nation's largest counties with 4,084 square miles, and has the largest population of any county in the nation - nearly 10 million residents who account for approximately 27 percent of California's population. As a subdivision of the state, the County is charged with providing numerous services that affect the lives of all residents, including law enforcement, tax collection, public health protection, public social services, elections and flood control.
Gateway Cities COG Air Quality Action Plan
Due in part to the heavy concentration of goods movement and industry in and around the Gateway Cities, the sub?region has historically experienced the adverse impacts of air pollution. Learn More