New California Tsunami Inundation Maps Released

On Thursday, December 17, 2009, representatives from the California Emergency Management Agency (Cal EMA), the California Geological Survey (CGS) and other state, federal, and local government officials participated in a press event to launch the newly updated California Tsunami Inundation Maps. Held at the Moscone Center in San Francisco, CA, and coinciding with the American Geophysical Union Conference, this media event provided all contributors opportunity to discuss the value of such maps in the area of emergency preparedness, and the value of the partnership between these agencies and Tsunami Research Center at the University of Southern California, which also contributed to producing the maps.

“California’s coast is subject to tsunamis from both local offshore earthquakes and underwater landslides, and distant sources, such as the 1964 Alaskan quake that spawned a deadly tsunami in Crescent City – it’s important to educate the public, and prepare them for the very real possibility of a tsunami emergency” said Cal EMA Secretary Matthew Bettenhausen.

This collaborative group, known as the California Tsunami Program, works closely with local government emergency planners to provide assistance and guidance to help prepare communities for the next tsunami. For more than two years specialist have been developing and modeling offshore earthquake and submarine landslide scenarios in order to identify the potential tsunami inundation for each coastal community.

“These maps show the maximum inland inundation as a product of the 40 different tsunami scenarios we looked at for California,” states Rick Wilson from CGS who was the state scientific lead on the project.

The resulting 130 maps, which are based on the most up-to-date methodologies, cover vulnerable areas along the California coast, about 50% of the state’s 840 mile-long coastline. These maps also encompass approximately 90% of the coast from Santa Barbara to the Mexico border, and 100% of the San Francisco Bay Area, the first time the state has developed tsunami inundation maps inside the Bay.

Funded through the National Tsunami Hazard Mitigation Program, the state program has worked with county and city emergency managers to help incorporate these tsunami inundation maps into their emergency response plans. The finalized maps are now available to the public through the Cal EMA and CGS websites.

[Source: California Emergency Management Agency press release]