Engineers Test Delta Levees with Simulated Earthquakes

UCLA engineers using mobile field shakers are conducting simulated earthquakes today to test the security of the fragile system of levees in the Sacramento–San Joaquin Delta.

Experts have projected that even a moderate earthquake in the 441,000-acre region could cause multiple levee failures, resulting in major flooding and an influx of saltwater from the San Francisco Bay that would halt water delivery for years, inundate farmland and sensitive wildlife habitat, and cause tens of billions of dollars in damage.

The researchers have constructed model levee in the Delta that measures 6 feet tall and 40 feet wide. To conduct the full-scale earthquake testing, they are using the nees@UCLA Earthquake Engineering Mobile Laboratory, which includes large shakers, actuators, instrumentation and a mobile command center. The test measured the potential deformation of organic foundation soils that could result in a levee breach.

The resulting data on the seismic vulnerability of California's levees could help guide state and federal lawmakers in determining how to best repair and strengthen levees — both those in California, which were built in the mid-19th century, and similar levees around the world.

The researchers hope to complete their results by this spring, when they will present their findings to the U.S. Army Corps and the Department of Water Resources.

Read more about today’s research in UCLA Today and the Sacramento Bee.