The California Coastal Conservancy reached agreement in December to bypass an obsolete dam on California�s Carmel River rather than dredging and buttressing the 90-year-old structure. The $84-million reroute and dam removal project will divert the river around the 106-ft high concrete arch San Clemente Dam built in 1921. The basin has since been swamped with 2.5 million cu yds of sediment, thereby reducing storage capacity from 1,425 acre-ft to 125 acre-ft. In 1992, the California Dept. of Water Resources Division of the Safety of Dams issued a safety order because of possible failure from a maximum flood event or an earthquake.
A 2008 Dept. of Water Resources study showed that the alternative of buttressing the dam would have cost $49 million, but not resulted in improved access for steelhead trout spawning or restoration of the lower river. California American Water, which draws supplies for its customers from the dam’s diversion point, agreed to pay the cost of buttressing with the California Coastal Conservancy and the National Oceanic and Atmospheric Administration picking up the rest of the price tag.