The 106-foot-tall dam was built more than 90 years ago and has back-filled with silt, said Robert MacLean of California American Water, the utility that owns the structure. It is deemed at risk of collapse in an earthquake and poses problems for the threatened steelhead trout population, wildlife experts say.
Like salmon, steelhead trout are hatched in fresh water, spend several years in the ocean and return to swim upstream to spawn. The San Clemente dam has a fish ladder that's supposed to allow the trout to make their upstream trek but it isn't very efficient.
Though originally built to provide a water source for the region -- Carmel, where the dam is located is 75 miles south of San Jose -- it now holds back less water than sediment that's piled up behind it.
The amount of dirt behind the dam would fill 250,000 dump trucks, officials say. What to do with all the dirt posed a significant problem so engineers devised a plan to reroute a half-mile of the river itself and leave the dirt where it is, the Los Angeles Times reported Sunday. The three-year project is to commence next month, the newspaper said.
"It really is innovative," said Joyce Ambrosius, Central Coast supervisor of the federal National Marine Fisheries Service, which has worked with the utility and the California State Coastal Conservancy on the dam removal.
The entire project will cost $84 million, with American Water putting up $49 million for the project. The state will chip in another $25 million and the federal government will contribute $2.4 million. The remainder will have to be raised by environmental groups. The Nature Conservancy has committed $1 million to the project, the Times said.