The 1965 Williamson Act currently shields 15.9 million acres from development. The program provides tax incentives to landowners who voluntarily place land in Williamson Act contracts, which typically last 10 years if not renewed. The landowners keep the land in agricultural production, and development rights remain with the land trust even if the land is sold. Farmland Mapping and Monitoring Program. Information in the report is valuable for providing a statewide perspective on land conversion.
Local governments use it to understand and plan land use in their communities.
The San Joaquin Valley Region, the state's farming heartland, led the state in the conversion of irrigated farmland to urban use, with 8,140 acres. There were significant increases in urbanization in three regions when compared to the 1992-94 reporting period. The Central Coast Region more than doubled its new urban acreage, from 2,048 to 4,743, while the Sierra Foothill Region jumped from 1,614 to 3,673 new urban acres.