Alquist Priolo Special Studies Zone Act

Alquist Priolo Special Studies Zone Act
California State Legislature
Full nameAlquist-Priolo State Special Studies Zone Act
Signed into lawDecember 22, 1972
Sponsor(s)Alfred E. Alquist and Paul V. Priolo
GovernorRonald Reagan
CodePublic Resources Code
ResolutionSB 520
Associated billsAmended 1974, 1975, 197, 1979, 1991, and 1993
Websitehttps://www.conservation.ca.gov/cgs/publications/sp42
Status: Current legislation

The Alquist-Priolo Earthquake Fault Zoning Act was signed into California law on December 22, 1972, to mitigate the hazard of surface faulting to structures for human occupancy.

The act in its current form has three main provisions:

1) It directs the state's California Geological Survey agency (then known as the California Division of Mines and Geology) to compile detailed maps of the surface traces of known active faults. These maps include both the best known location where faults cut the surface and a buffer zone around the known trace(s);

2) It requires property owners (or their real estate agents) to formally and legally disclose that their property lies within the zones defined on those maps before selling the property; and

3) It prohibits new construction of houses within these zones unless a comprehensive geologic investigation shows that the fault does not pose a hazard to the proposed structure.

The act was one of several that changed building codes and practices to improve earthquake safety. These changes are intended to reduce the damage from future earthquakes.