Overview of California Dam Safety Inundation Map Program

ABSTRACT ONLY - California’s Division of Safety of Dams (DSOD) regulates dams with respect to safety to prevent dam failure for safeguarding life and protecting property. DSOD’s Dam Safety Program continues to evolve and expand to meet and exceed industry best practices for public safety. In a recent step to protect the public and property through enhanced emergency preparedness, dam owners are required to have an emergency action plan (EAP) based on inundation map(s) for a dam and its critical appurtenant structures. As mandated by California Senate Bill 92, signed into law on June 27, 2017, owners of all but low hazard jurisdictional dams are required to prepare EAPs containing DSOD approved inundation maps for the hypothetical failures of the dam and its critical appurtenant structures. The EAPs, containing the DSOD approved maps, are required to be submitted to California Governor’s Office of Emergency Services (Cal OES) for review and approval. In response to the requirements of Senate Bill 92, DSOD initiated an Inundation Map Program, promulgated new Inundation Map Regulations, and acquiring necessary resources for reviewing and approving inundation maps submitted by dam owners under a fast-tracked timeline. This paper provides an overview of the implementation of DSOD’s Inundation Map Program and highlights some of DSOD’s internal guidelines for independent inundation map review and approval process, as well as the potential use of inundation maps in risk informed decision making.