The nearly 200,000 people evacuated Sunday from the area surrounding the Oroville Dam in Oroville, California, are now free to return home, Butte County Sheriff Kory Honea announced Tuesday afternoon.
Following successful efforts to lower Oroville Lake’s water level and address erosion in its spillways, officials reduced the evacuation order to an evacuation warning, allowing more than 188,000 residents to return to their homes and businesses.
While there are still repairs to be done and months of construction ahead to permanently repair the spillways, officials said the immediate threat had been mitigated enough to lift the evacuation order.
The episode was “a stark reminder that the forces of Mother Nature can create emergency situations requiring swift and immediate action,” Honea said.
Residents should still be prepared for the possibility of another evacuation order if conditions change, officials said Tuesday.
After both the dam’s main and emergency spillways showed signs of eroding, forcing precautionary evacuations Sunday evening, crews have been working to lower Lake Oroville’s water levels by 50 feet and temporarily fill holes in the dam’s two spillways with large sacks of rocks.
The man-made lake feeds into the Feather River, which runs through downtown Oroville and other populated areas that could be devastated by a flood if the spillways were to be further destabilized.
The California Department of Water Resources, which runs the dam, reported Tuesday morning that water levels were dropping by three to four inches per hour.
While weather conditions have been fair this week, the National Weather Service forecasts three storms lined up to hit Northern California. Heavy rain is expected to return Wednesday night and continue throughout the week. Officials don’t expect that rain to overwhelm the reservoir as crews continue draining water and making repairs.
President Trump on Tuesdayapproved a request by California Gov. Jerry Brown for federal disaster assistance for the area. The Federal Emergency Management Agency announced that three countries near Lake Oroville, as well as other parts of California hit by massive storms in recent weeks, will receive assistance.
But the dam and its spillways will likely face other storms in the near future. The rainy season typically continues through March, and spring will bring runoff from melting snowpacks.
“That will be the challenge at Lake Oroville in the coming months — keeping people downstream safe while managing the dam itself,” atmospheric scientist and Washington Post weather editor Angela Fritz wrote Tuesday. “If the past is any indicator of the future, they should prepare for more precipitation, not less.”