It's a sight that usually means California is having a good winter and water supplies are healthy. This week, operators at Oroville Dam, the tallest dam in the United States, which holds back California's second-largest reservoir, opened the spillway gates and began releasing billions of gallons of water down the massive concrete spillway into the Feather River below. The reason? It's not to waste water. But to prevent potential floods.
California's largest reservoir, Shasta Lake, is at 123% of its historical average for this time of year, measuring at 72% capacity as of Monday, according to the California Department of Water Resources. The reservoir's current surface elevation is 1,019 feet, which is not far from its full capacity, according to Monday data from the Bureau of Reclamation, the agency that oversees the reservoir. When Shasta is full, the elevation is 1,067 feet above sea level.