Dam Owner Responsibilities

Know Your California Dam Safety Laws

In California, dams are regulated by the Department of Water Resources Division of Safety of Dams (DSOD) based on several factors including the height of the dam and the storage capacity of the reservoir. Federal dams are excluded from state regulation, and some non-federal dams also may be exempt. Currently, approximately 1,250 dams in California fall under state jurisdiction. The DSOD website provides summaries of laws and regulations pertaining to dams.

DSOD determines the hazard classification of a dam based on the potential consequences resulting from the uncontrolled release of its reservoir contents because of a failure or wrongful operation of the structure. A highly technical set of factors and criteria that are explained on the DSOD website will determine hazard classification.

Inundation maps are a crucial part of a comprehensive EAP, and in California these maps have been created for most large dams. EAPs and inundation mapping of HHP dams are under the jurisdiction of the California Office of Emergency Services (CalOES) Dam Safety Program within the Hazard Mitigation division. California legal code requires dam owners to submit copies of inundation maps developed by civil engineers to the CalOES. Copies of these maps are also provided to the appropriate public safety agency of any city and/or county likely to be affected. Most local agencies overlay these inundation maps onto their land parcel map systems, such as those used by assessors.