The Alquist-Priolo Earthquake Fault Zoning (AP) Act was passed into law following the destructive February 9, 1971 Mw 6.6 San Fernando earthquake. The AP Act provides a mechanism for reducing losses from surface fault rupture on a statewide basis. The intent of the AP Act is to ensure public safety by prohibiting the siting of most structures for human occupancy across traces of active faults that constitute a potential hazard to structures from surface faulting or fault creep.
Thirteen new and revised Official Alquist-Priolo Earthquake Fault Zone Maps Released September 21, 2012. Areas covered include parts of Alameda, Imperial, Riverside, San Diego, and Ventura counties. This release introduces a new graphic presentation of these regulatory zone maps. Click here to view or download the new and revised Official Maps.