State, Corps study: One in five Californians faces flood threat

U.S. Army Corps of Engineers Sacramento District
Published April 3, 2013
Flooding near the Sutter Buttes, Calif., in 1997.

Flooding near the Sutter Buttes, Calif., in 1997.

SACRAMENTO, Calif. – One in five Californians lives in a flood plain and nearly everyone in California is at risk from flooding.

That’s the warning delivered by a new, comprehensive report on flood risk throughout the state, developed by the California Department of Water Resources and the U.S. Army Corps of Engineers’ South Pacific Division. “California’s Flood Future: Recommendations for Managing California’s Flood Risk,” released in draft for public review today, describes for the first time the specific flood threats and their consequences in every county in California.

“What we found is that floods have the potential to affect just about everyone who lives in California,” said Kim Carsell, the Corps’ lead planner for the project. “Even if you’re not flooded, things you depend on – utilities, hospitals, the farms that grow your food – could be. So a flood would still be a big problem for you; and really, for the nation.”

The report is intended as a guide for how California can most effectively reduce the threat of its growing flood problem in the near and long term.

Every one of California’s 58 counties has had a major flood during the last 20 years, the report revealed, and more than $575 billion in infrastructure and $7 billion in crops are exposed to flooding. California has one of the world’s largest economies, so a major flood here would have national and even international impacts.

The report also concludes that existing flood risk reduction infrastructure in California does not meet the state’s needs, and that even currently-planned future projects would not be enough to address its growing flood threats.

Historically, projects to reduce flood risk in California have often been built to address isolated, local problems - a levee here, a dam there - not always considering the connections between flooding issues within their larger watershed. Among its seven major recommendations, the report concludes that the future of flood risk reduction is about designing and prioritizing projects with multiple benefits: projects that reduce flood risk throughout a watershed, while also restoring the environment and improving water supply reliability.

Staff from each of the three South Pacific Division Corps districts in California – San Francisco, Los Angeles and Sacramento – contributed to “California’s Flood Future,” which received technical review from the division’s fourth district in Albuquerque. The study team, including Corps staff as well as staff from the California Department of Water Resources, consulted 142 local agencies throughout the state to compile the data that informs the report’s conclusions. The report was funded by the state of California.

California’s lead planner for the report, Terri Wegener, said it is just the first phase in a long-term effort to re-imagine how the state manages flood risk and plan projects that make the most efficient use out of limited resources.

“It is much smarter and more cost effective to reduce flood risk now than to spend billions of dollars trying to recover from a major flood,” she said.