Butte County Sheriff Kory Honea said Tuesday that experts found no additional damage to "compromise the overall integrity" of the spillway. He says the lake behind Oroville Dam also is capable of handling additional rain from an expected storm this week.
Honea said that residents should stay prepared in case the situation changes. He says the water level at the lake behind Oroville Dam, the nation's tallest, is low enough to accommodate an expected storm.
Officials had ordered nearly 200,000 residents to flee to higher ground Sunday after fearing a never-before-used emergency spillway was close to failing and sending a 30-foot wall of water into communities downstream.
Over the weekend, the swollen lake spilled down the unpaved emergency spillway for nearly 40 hours, leaving it badly eroded. The problem occurred six days after engineers discovered a growing hole in the dam's main, concrete spillway.
Officials defended the decision to suddenly call for mass evacuations Sunday, just a few hours after saying the situation was stable, forcing families to rush to pack up and get out.
"There was a lot of traffic. It was chaos," said Robert Brabant, an Oroville resident who evacuated with his wife, son, dogs and cats. "It was a lot of accidents. It was like people weren't paying attention to other people."
A relay of helicopters started moving dirt, rocks and concrete onto the crumbling emergency spillway while keeping an eye on the damaged main spillway using tools as sophisticated as night-vision goggles.
Officials said the spillway has been stable for four days, and that the incoming storms are much smaller than the storms that have helped fill the reservoir so high, allowing them to lift the order.
The mandatory evacuation order has been reduced to an evacuation advisory in Sutter County. Please Drive Safely. [1/2]— County of Sutter (@CountyofSutter) February 14, 2017
Any resident displaced by the evacuation may return home at 1:00 p.m. All residents advised to maintain heightened level of awareness. [2/3]— County of Sutter (@CountyofSutter) February 14, 2017
Evacuation Advisory considers probability area will continue to be affected & residents need to remain prepared for Evacuation Order. [3/3]— County of Sutter (@CountyofSutter) February 14, 2017
VIDEO: Oroville Dam emergency spillway at risk of failing