Disclosure of Seismic Hazard Zone​s

The Natural Hazards Disclosure Act, effective June 1, 19​​98 (as amended June 9, 1998), requires that sellers of real property and their agents provide prospective buyers with a "Natural Hazard Disclosure Sta​​tement" when the property being ​sold lies within one or more state-mapped hazard areas, including a Seismic Hazard Zone.

​​What is a Seis​mic Hazard Zone​?​

​​A Seismic Hazard Zone is a regulatory zone that encompasses areas prone to liquefaction (failure of water-saturated soil) and earthquake-induced landslides. What does it mean to be located within a Seismic Hazard Zone? It means that the state has determined that there is likely that weak soil and/or rock may be present beneath the property. If present, these weak materials can fail during an earthquake and, unless proper precautions are taken during grading and construction, can cause damage to structures. If a property is undeveloped, a site-specific investigation by a licensed engineering geologist and/or civil engineer may be required before the parcel can be subdivided or before most structures can be permitted. If the property lies within a mapped Seismic Hazard Zone, that fact must be disclosed by the seller to prospective buyers.

How does the Seismic Hazards Mapping Act ​​​work?

The law requires the State Geologist to establish regulatory zones (Zones of Required Investigation) and to issue appropriate maps (Seismic Hazard Zone maps). These maps are distributed to all affected cities, counties, and state agencies for their use in planning and controlling construction and development. Single family frame dwellings up to two stories not part of a development of four or more units are exempt from the state requirements. However, local agencies can be more restrictive than state law requires.

Before a development permit can be issued or a subdivision approved, cities and counties must require a site-specific investigation to determine whether a significant hazard exists at the site and, if so, recommending measures to reduce the risk to an acceptable level. The investigation must be performed by state-licensed engineering geologists and/or civil engineers.

Disclosu​​re Requirements

Effective June 1, 1998, the Natural Hazards Disclosure Act, requires that sellers of real property and their agents provide prospective buyers with a "Natural Hazard Disclosure Statement" when the property being sold lies within one or more state-mapped hazard areas. If a property is located in a Seismic Hazard Zone as shown on a map issued by the State Geologist, the seller or the seller&quots agent must disclose this fact to a potential buyers. The law specifies two ways in which this disclosure can be made. One is to use the new Natural Hazards Disclosure Statement as provided in Section 1102.6c of the California Civil Code. The other way is to use the Local Option Real Estate Disclosure Statement as provided in Section 1102.6a of the Califor​nia Civil Code. The Local Option Real Estate Disclosure Statement can be substituted for the Natural Hazards Disclosure Statement only if the Local Option Statement co​ntains substantially the same information and substantially the same warning as does the Natural Hazards Disclosure Statement.

In addition to Seismic Hazard Zones, information shown on official maps of Earthquak​e Fault Zones and other state and federal maps of natural hazards also must be disclosed.

​How can I find out​​ if a property is located in a Seismic Hazard Zone?

Official Maps of Seismic Hazard Zones are issued periodically by the California Geological Survey in compliance with the Seismic Hazard Mapping Act. The easiest way is to find out​​ if a property is located in a Seismic Hazard Zone is to use the California Earthquake Hazards Zone Application​​ or search our collection of online maps. You can also visit one of the California Geological Survey offices​ (call ahead), or your city or county office. Your county assessor, recorder, and planning agency are all required to post notices that advise the public of the availability and location of Seismic Hazard Zone Maps affecting that county (Public Resources Code 2696c). Consult the appropriate local agency if you are uncertain whether a property lies within a Seismic Hazard Zone.

​How can I be certain that the map I have is an Official Map of Seismic Hazard Zones?

The California Earthquake Hazards Zone Application​​ is the best official resource for locating Seismic Hazard Zones; however, if you have a paper or PDF version of a Seismic Hazard Zone Map, only official maps will have the following text displayed prominently:

[NAME] QUADRANGLE

SEISMIC HAZARD ZONES

Delineated in compliance with Chapter 7.8
Division 2 of the California Public Resources Code
(Seismic Hazards Mapping Act)

OFFICIAL MAP [or] REVISED OFFICIAL MAP

Released: [Date]

[Signature​]
STATE GEOLOGIST