OROVILLE, California--Californians who were ordered to evacuate due to a threat from the tallest dam in the United States can now safely return to their homes and businesses may reopen, a county sheriff said on Tuesday.
A previous evacuation order has been reduced to an evacuation warning, Butte County Sheriff Kory Honea told a news conference, after water management officials drained enough water from the Oroville Dam to relieve pressure and avert a catastrophe. The warning means that people can return home but should be prepared to evacuate again if necessary, Honea said.
Officials had ordered 188,000 people living down river from the dam to evacuate. Both the primary and backup drainage channels of the dam, known as spillways, were damaged after a buildup of water that resulted from an extraordinarily wet winter in Northern California that followed years of severe drought.
The greatest danger came from the emergency spillway, which allows water out of the reservoir when capacity is reached. Though damaged, the primary spillway was still useable, officials said.
More rain was forecast for as early as Wednesday and through Sunday, according to the National Weather Service, but the state Department of Water Resources said the upcoming storms were unlikely to threaten the emergency spillway.
Swift action by the department to shore up both spillways while also relieving pressure on the dam averted the immediate danger of a dam failure, Honea said. A failure could have unleashed a wall of water three stories tall on towns below. State officials used 40 trucks carrying 30 tons of rock per hour to reinforce the eroded area while two helicopters dropped rock and other materials into the breach.
