Nearly 200,000 Northern Californians who live downstream of the country's tallest dam were allowed to return home Tuesday after two nights of uncertainty, but they were warned they may have to again flee to higher ground on a moment's notice if hastily made repairs to the battered structure don't hold. The fixes could be put to their first test later this week with the first of a series of small storms forecast for the region. But the real test is still to come in the weeks ahead when a record amount of snowfall melts in nearby mountains, the AP reports. "There is the prospect that we could issue another evacuation order if the situation changes and the risk increases," Butte County Sheriff Kory Honea said Tuesday.
Some 40 trucks have dumped 30 tons of bags loaded with sand, concrete blocks, and boulders every hour into the damaged areas below the Oroville Dam, while helicopters have dropped bags of rocks and cement blocks onto the problem sites. Preliminary estimates say permanently fixing the hole in the main spillway at the dam could cost $100 million to $200 million, acting California Department of Water Resources chief Bill Croyle said. Experts are drawing up plans for repairs that will begin after the spring runoff season ends. Gov. Jerry Brown said late Tuesday that the Federal Emergency Management Agency approved his request for federal assistance with the dam situation. (Read more Oroville Dam stories.)