UPGRADE BEGINS AT CASITAS DAM; GROUNDBREAKING HELD FOR EARTHQUAKE PROJECT.

Byline: Don Holland Staff Writer

Concerned that an earthquake could rupture Casitas Dam and send a 300-foot wall of water toward Ventura, officials formally broke ground Thursday on a $42 million construction project to bolster the earthen dam.

A key safety component of the project is a series of seven sirens to sound an early warning should the dam ever fail that are to be up and working next month, said Jeff McCracken, public affairs director with the federal Bureau of Reclamation, which owns the lake and which is paying for 85 percent of the project.

``We held a number of public meetings, and one of the things we learned is that they wanted some sort of an early warning system,'' McCracken said.

Officials estimate up to 400 people along Coyote Creek and the Ventura River could be killed if the dam were to break without warning.

In case of imminent rupture, the dam tender, who monitors the dam from a house at the site, would trigger the solar-powered sirens.

Last November, the bureau made the dam upgrade project a priority after determining that a 7.0-magnitude earthquake probably would rupture the 40-year-old structure.

``This is a very special day for all of us to be out here and actually see this come to fruition,'' Rep. Elton Gallegly, R-Oxnard, said during a groundbreaking ceremony.

Gallegly hailed local and federal officials for quickly joining forces to repair the dam, which is maintained by the Casitas Municipal Water District.

``We don't want to send the message out that the sky is falling,'' Gallegly said. ``It would take a tremendously catastrophic event to cause a failure here. But the basis of this whole program is that a good offense is your best defense. That's what we're doing here. We're not responding to something that is about to fail.''

Work crews will dig a massive trench at the rear of the dam and then haul in 1.5 million cubic yards of soil to support the structure. Officials are worried that a major earthquake on the nearby Red Mountain Fault could ``liquefy'' the sandy soil at the base, causing the dam to break.

The plan also calls for widening the crest of the dam from 40 feet to 110 feet.

``This dam is 40 years old, so this is like a '59 Chevy that now needs seat belts and safety glass,'' McCracken said. ``We're bringing it up to standards. If we built this dam today, that's what we'd do.''

When the project is completed in December 2000, the dam should be able to withstand about a 7.1-magnitude earthquake within three kilometers, or even a direct hit from a small nuclear weapon, Gallegly said.

Although Vista Point will be closed during construction, camping, fishing and boating at the lake will continue as usual.

CAPTION(S):

2 Maps

Map: (1--2 -- 1 ran in Conejo Edition only) DAM REPAIRS

A $42 million repair project is under way to strengthen Lake Casitas Dam against a major earthquake. While recreational uses of the lake will not be affected, Vista Point, a popular scenic spot, is temporarily closed.