Assignment 7

Largest dam in state history torn down

Wednesday, May 08, 2013

Monterey County supervisors gave their OK for the largest dam removal project in state history. The San Clemente Dam is eighteen miles from the coast in the Carmel Valley.

The 90-year-old, 106-foot-tall dam was once a major source of water on the Monterey Peninsula. But it has reached the end of its useful life.

"The dam was deemed to be seismically unsafe in 1995," said California American Water spokesperson Catherine Bowie.

She added that, "as the water provider we had to do something to resolve that safety issue."

So the company set out on a plan to retrofit the dam.

"But then the natural resource agencies from the state and federal levels stepped in and said, we want to do more than solve the safety issue, strengthen the dam with concrete, we want to see if we can actually remove the dam," said Bowie.

Tearing down a dam isn't as simple as you think. You can't just knock it down and let the water go. That's because sediment from upstream has backed up behind the dam. It would take 250,000 dump trucks to haul away all the silt behind this dam. Just letting it flow downstream may harm endangered steelhead trout that use the river to breed. The species is already on the verge of vanishing from the Carmel River.

Joyce Ambrosius with the National Marine Fisheries Service said the steelhead numbers have been dwindling over the last couple of years. "It's been down to 91 in the last couple of years, where in the 1960's it was in the thousands of fish. So we are right on the edge of them blinking out here," she said.

Ambrosius has spent the last 15-years waiting for the dam to come down. She says the dam removal can't come soon enough, "Right now the fish have to come up a very steep fish ladder. Some of the steps are three feet tall, that only the strongest fish can make it up just to get past the dam."

Tearing the dam down may open the way to the species recovery. There is now a plan in place to do just that.

Project Manager Jeff Szytel explained, "We're going to build a diversion dike to permanently reroute the river around this existing the sediment." He added that they will "then restore the site, to return health to the river."

The cost to upgrade the dam was $49 million. Removing the dam will cost $83 million. The utility balked at the idea of picking up the whole tab, so Rep. Sam Farr, D-Salinas, stepped in to broker a compromise.

"There is no opposition to this. This is absolutely the right thing to do. You don't have those moments very often in politics," said Farr.

Under the agreement, California American rate-payers will pay $50 million towards the demolition through increases in their water bills. The state Coastal Conservancy and the National Oceanic and Atmospheric Administration committed to raising the additional $35 million through a combination of public funding and private donations.

"It's been an amazing project to work on and it will be the biggest dam removed in California. It's very exciting," said Trish Chapman of the California Coastal Conservancy, a state agency.

When the project is done, the area will be opened to the public. The federal government will rededicate 928 acres as parkland.

Preliminary work on the dam removal will begin this summer. It will take about three years to remove the entire structure.

Written and produced by Ken Miguel

(Copyright ©2014 KGO-TV. All Rights Reserved.)

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monterey county, water, animals in peril, assignment 7, dan ashley
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