CASITAS SPRINGS : Earthquake Drill Pleases Agencies

In a realistic training drill, county emergency workers responded to a 5.0 earthquake that would have damaged Casitas Dam south of Ojai.

It would have taken officials 1 1/2 hours to begin evacuations after the quake damaged the earthen dam, officials said. But they were happy with the agencies’ response.

“We were real pleased. It went real well,” said Wendy Haddock, program manager with the Sheriff’s Department.

A moderate earthquake was simulated instead of a large one, she said, to allow agency coordination at a time when no other damage in the county would have occurred.

In the drill, the dam was damaged but held after the imaginary quake, the epicenter of which was along the Red Mountain fault that runs under the dam.

The training exercise was undertaken Sept. 27 by the Ventura County Sheriff’s Department office of emergency services after three months of planning. Casitas Municipal Water District, which operates the earthen dam, released a report on the exercise this week.

The scenario had the quake occurring at 7 a.m. on a Thursday. Participants such as the Red Cross, California Highway Patrol and the county superintendent of schools were given no warning of when the drill was to take place.

At 8:30 a.m., Casitas staff reported that the dam had been damaged but was holding.

Evacuation of about 3,000 residents below the dam was recommended as a precaution.

The dam’s main outlet was damaged in the scenario, which would have left the city of Ventura without its 9,000-acre-foot water supply from the lake.

If the dam completely fails, about 12,000 residents would be in the inundation path along Ventura River to the ocean, Haddock said.