Alquist-Priolo Earthquake Fault Zones
In the context of location intelligence and home buying, Alquist-Priolo Earthquake Fault Zones are designated areas in California that encompass active surface traces of faults. These zones were established by the Alquist-Priolo Earthquake Fault Zoning Act of 1972, which was enacted to mitigate the hazard of surface fault rupture to structures for human occupancy.
Key aspects of Alquist-Priolo Earthquake Fault Zones include:
- Active faults: The zones are delineated around faults that are deemed sufficiently active and well-defined. An active fault is one that has ruptured in the last 11,000 years (Holocene time).
- Regulatory requirements: Within these zones, the act prohibits the construction of new buildings for human occupancy without a comprehensive geologic investigation. The investigation must demonstrate that the proposed structure is not located across an active fault trace.
- Setback requirements: If an active fault is identified during the geologic investigation, a minimum 50-foot setback from the fault trace is typically required for new structures.
- Disclosure: Sellers of real property within an Alquist-Priolo Earthquake Fault Zone are required to disclose that the property lies within such a zone at the time of sale.
When considering purchasing a home in California, it is essential to determine whether the property lies within an Alquist-Priolo Earthquake Fault Zone. Homes within these zones may be subject to additional development restrictions, potentially limiting future expansion or renovation plans. Additionally, the proximity to an active fault may impact the home's value and insurability.
