Before a project can be permitted, cities and counties must require a geologic investigation to demonstrate that proposed buildings will not be constructed across active faults. An evaluation and written report of a specific site must be prepared by a licensed geologist.
If a property is located in an earthquake zone, a geologic fault hazard investigation is necessary before any new construction is permitted to proceed.
If an active fault is found, a structure for human occupancy cannot be placed over the trace of the fault and must be set back from the fault (generally 50 feet).
Source: Hernandez, J.L., (2014), CGS Fault Evaluation Report FER 253 Supplement No. 1