TheBakersfieldCalifornian.com

LAKE ISABELLA -- Rep. Kevin McCarthy wanted something on paper -- something without a lot of wiggle-room.

The Bakersfield Republican got what he wanted Thursday from the U.S. Army Corps of Engineers: a concrete timeline on how and when the two 60-year-old dams here will be made safer over the next decade.

"There's never been a definite timetable," McCarthy said Thursday morning, just minutes after meeting with Army Corps leaders and touring the main dam.

"I wanted something on paper," McCarthy said. "I wanted a process that everyone can see."

The Army Corps, which built the dams in the early 1950s and remains responsible for them today, has been working on a "fix" for the earthen dams since 2006, when it was discovered that water seeping under the structures posed a threat to the structural integrity of the two dams.

Since then, the discovery that an earthquake fault running beneath one of the dams is active -- and the determination that an extreme 5,000-year "Noah's flood" could bring down the dams -- has heightened concerns, resulting in years of risk assessment, engineering, seismic and hydrologic studies, and communication with the public about potential dangers, impacts and solutions.

All of that is well and good, McCarthy said, and he thanked the Corps for its efforts.

But Kern River Valley residents who rely on the tourism the lake generates -- and some 300,000 people downstream who rely on the dams to prevent a massive wall of water from roaring down the Kern River Canyon like a runaway train -- need to be in the know.

U.S. Army Col. Bill Leady, the commander of the Corps' Sacramento district, said he's perfectly happy to keep the process as transparent as possible.

"The concerns of the community have affected our plans, not what we're going to do ... but how we're going to do it," he said.

Leady said the problem and the potential solutions are so complex, it has required a careful, painstaking process.

"We have deliberately done this at this pace," he said.

For the first time Thursday, Corps leaders made it clear that they are going with one of the most "robust" alternative fixes, even though the choice isn't yet official.

At a cost estimated at between $400 million and $600 million, Leady said the final alternative will include raising the crest of the dams by up to 16 feet, adding a buttress and building a wider spillway.

The Corps' own complex, located between the two dams, will have to come down. So will the U.S. Forest Service office nearby.

Approximately one mile of Highway 155 will have to be relocated as will a smaller portion of Highway 178.

"This is a very critical project for us. This is the No. 1 priority in this region for dam safety," said Joe Calcara, director of programs for the Corps' South Pacific Division, which includes four operating districts centered in Albuquerque, Los Angeles, Sacramento and San Francisco

Calcara said he wants the process, expected to be finished in 2022, to be "seamless," effective and efficient.

According to the timeline, environmental impact studies and a fish and recreation plan should be complete by the end of 2013. Investigating and designing the construction and other aspects of the huge project are not expected to be finished until early 2016.

There will be several moving parts, but the first major construction projects will be the realignment of highways 155 and 178, beginning in late 2014 and ending in late 2016, according to the timetable.

Excavation of the emergency spillway, designed to supplement the smaller current spillway in the event of what Leady referred to as an exceedingly rare "Noah's flood" event, will begin in late-2016 and continue for more than three years.

Another massive earth-moving operation will be the buttress to strengthen the weakest link, the auxiliary dam. The project would use rock, concrete or other materials to compact the foundation against the dam, thereby strengthening and stabilizing the dam itself.

That project is expected to begin in mid-2017 and continue through early 2020. A buttress for the more stable main dam is also in the plans, but it would take less than two years to complete, according to the timeline.

Artificially lowering the lake level to allow work on the Borel Canal is one of the most controversial components of the dam project. But Corps leaders promise to do it in the fall and winter of 2020-2021 to avoid impacting the height of the tourist season.

Corps officials are careful to say the timeline is subject to change.

But McCarthy didn't appear too keen on that possibility.

The timetable is a way to ensure "accountability," McCarthy said. "That's what we want."