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Earthquake Fault Zone


Area within a close proximity of naturally occurring earth plates. If property being sold or transferred is within a close distance of an earthquake fault zone, the seller or transferor party must disclose this information to the buyer or transferee.


An earthquake fault zone is considered an area that is within a quarter mile of an active fault. Property’s nearing or on the earthquake fault zone or at increased risk of damage due to strong naturally occurring movement. To reduce the chance of damage and loss of human life and property damage, the government passed the Alquist-Priolo Earthquake Fault Zoning Act.

The Alquist-Priolo Earthquake Fault Zoning Act regulates development taking place in areas on or nearing earthquake fault zones. The act considers potential dangers associated with structures nearing or on fault zones to prevent widespread loss of life and property damage. Furthermore, it helps regulate a city’s zoning laws and issues permits for the property’s development based on the relative risk associated with having a property in areas considered at risk.

After the passage of the earthquake fault zoning act, landowners who are building or improving properties within the fault zone must provide a geologic report to their city or county building and safety office. Sellers and real estate agents of properties found near or on a fault zones must disclose the presence of the fault zone next to the property. This gives buyers the necessary information they need when deciding to purchase the property. Furthermore, this information gives buyers the ability to do their due diligence regarding how much it would cost to develop a property built within an earthquake fault zone.