2020 Adjusted Urban Area

Caltrans is responsible for the decennial production of the Adjusted Urban Area Boundaries for the State of California. The CA 2020 adjusted urban area file represents the current Federal Highway Administration (FHWA) approved Caltrans adjusted urban area boundaries.The Urban Area Boundaries are separated into two classifications based on population:Small Urban Areas: population ranging from 5,000 to 49,999Urbanized Areas: population of 50,000 or moreAccording to Title 23 U.S.C. 101(a)(35) and (36), Small Urban and Urbanized Area boundaries are to be adjusted in cooperation by responsible State and local officials, and subject to approval by the Secretary of Transportation. Adjustments may include the addition of significant transportation corridors and areas of growing urbanization.