I don’t know how I missed this news, but earlier this summer, the California Public Utilities Commission (CPUC) voted 4 to 1, in favor of removing the antiquated San Clemente Dam on the Carmel River.  The National Marine Fisheries Service (NMFS), identified the Carmel River as the most critical watershed on the Central Coast of California, for restoring the numbers of South-Central Coast Steelhead.

I’m not sure I’d have much confidence in conditions like these. Photo courtesy of Carmel River Watershed Conservancy.

The San Clemente dam, which was built in 1921 and is 18 miles up river from the Pacific, is ninety percent silted in and provides no water supply function whatsoever.  Before the dam was built, an average of 20,000 steelhead were able to navigate the entire 36 miles of the Carmel River.  Today the average number of steelhead is 338.  The dam isn’t completely to blame of course, but it has cut off the most important spawning habitat in the watershed.  In 1992, state officials determined that the dam is also in danger of collapsing in the event of an earthquake, which could result in the flooding of lower valley, making the decision that much more important.

The San Clemente Dam on the Carmel River after a heavy rainfall. Photo courtesy of NOAA.

In addition to opening up and improving some 25 miles of high quality spawning habitat for the Carmel River steelhead, removal of the San Clemente Dam will also be an historic precedent, as it will be the largest dam ever taken down in California so far.

California American Water Company (Cal-Am) , which operates the dam, conducted extensive studies to address the issues and determined if removal of the dam was the best option.  The result would cost more than $80 million, nearly twice the expense of other feasible, but less desirable options.  NMFS and the California Coastal Conservancy began negotiating with Cal-Am in support of dam removal.  They reached out to other stakeholders for support, and a remarkable coalition evolved.  Conservation groups like Trout Unlimited, government agencies, and local businesses all committed to taking out San Clemente Dam.

“This project is a laudatory example of innovative thinking, as it provides a creative solution to a host of problems,” says PUC Commissioner Catherine Sandoval. “It is a historic opportunity to protect people from potential flood damage, meet earthquake safety guidelines, protect endangered species, and provide significant environmental benefits to the public and wildlife.”

The San Clemente Dam removal will be launched in September, 2012, and will take three years to complete.