Work continues on Isabella dam studies, evacuation plans

Geologists are studying earthquake faults near the Isabella dams, and Kern County emergency planners are putting the final touches on a dam failure evacuation plan.

The work follows discoveries of new concerns about the dams, which Eyewitness News was first to uncover in 2006.

The evacuation plans are set to go to county and Bakersfield leaders this summer for approval. The current geology studies are looking at the Kern Canyon Fault both south and north of Lake Isabella.

On Tuesday, the crew was working in a couple trenches dug into the fault about eight miles north of Kernville.

"We're doing this so we can determine the best fix for the project," Corps of Engineers geologist Ronn Rose told Eyewitness News. "Determine what the issues are at the dam and the best fix. Scientifically, it's incredibly exciting."

Rose said the crews are marking layers found along the fault, and that will help determine what could happen in the future. "What we need to find out is the size, what maximum earthquakes could occur," Rose said. He added their studies so far have proved the fault is active south of Lake Isabella. No they need to see if it was active at the same time to the north.

"Whether or not ruptures could around this bend through Kernville -- and this whole length of this fault -- will determine how big a potential earthquake can be," Rose said.

Meanwhile, Kern County emergency planners are working on evacuation plans, if there are problems at the dam. Emergency Services Manager Georgianna Armstrong has new guidelines from the Corps on what they will do, if any problems are seen at the dams.

"These are technical conditions that the U.S. Army Corps would report to us, and what actions we would take -- based on each of the levels and their observed conditions," Armstrong said.

If the Corps spots changes or problems, then local emergency crews would decide if they need to warn people or call for an evacuation, for example.

The county also has a new Emergency Operations Center on Panorama Drive, and it's another sign of progress in disaster preparations. "Over the last, I'd say year to two years we've really made dramatic strides in being prepared," said Kern County Fire Deputy Chief Mike Cody.

As for any type of local disaster response, Armstrong says she has one big concern. "The access and functional needs plan, that one stays with me all the time. We will not be the next Katrina."

In Hurricane Katrina in New Orleans, too many sick and disabled people did not survive. Armstrong says Kern County will have a disaster response and evacuation plan that will take care of them.

What about evacuating everyone in a disaster -- especially if the Isabella dams failed? "We've still got some areas that we're trying to firm up," Cody said. The fire chief said they need more specifics on evacuation routes, locations, and how many people would need them.

After the new concerns were discovered at the Isabella dams, the Corps of Engineers ordered the reservoir could not be filled above 66 percent of capacity. "Below the 66 percent reservoir level, the dam is considered safe, it's within acceptable safety parameters," Armstrong said.

But, according to studies done by the Corps of Engineers, if the dams failed for some reason -- water would rush down the Kern River Canyon and cover much of Bakersfield and wide areas to the south, west and north.

That's why the evacuation plans are being drawn up. Armstrong said they're in the process of finalizing the dam evacuation plan, and it will go to the Kern County emergency council in June, and then on to Kern County and Bakersfield City officials.

Armstrong said then they want to have what's called a "table top" exercise of the disaster response plans later this year, and a large drill of the plans by the end of next year.

Emergency crews say practicing the plans are a must. "After we've taken our plan out, and we've kicked it, and poked holes in it to see what could go wrong -- then I'll feel better," Armstrong said.

But, the work to fix the dams is also moving ahead. From the Corps, geologist Ronn Rose said the studies of the Kern Canyon fault will continue through the summer. They plan to dig trenches in two more locations north of Kernville.

Rose also says the Corps is getting all the funds they need for the Isabella Dam studies. He said they're getting about $8 million a year. But, it will take time to get all the data they need to design the right "fix" for the dams. "We want to do this right," Rose said.

At this point, Rose said by 2011 they hope to decide on what type of a "fix" is needed. It's hoped they can have that project designed by 2013, and start construction by 2014.
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