The Butte County Sheriff has released an announcement on Tuesday allowing all of the nearly 200,000 residents near the Oroville Dam who were evacuated on Sunday night to return home.
Efforts to lower the level of the lake are succeeding, and large rocks are being used to plug a hole in the emergency spillway that threatened its collapse.
The Butte County Sheriff’s full statement, posted on Facebook, is as follows:
Due to lower lake levels, further inspections, ongoing work to shore-up the Oroville Dam emergency spillway and updated weather forecasts, effective at 1:00 p.m. today, the Evacuation Order for the Oroville Dam Spillway Incident has been reduced to an Evacuation Warning. Any resident displaced by the evacuation may return home at 1:00 p.m.; however all residents are advised to remain vigilant and prepared as conditions can rapidly change. People who have special needs or require extended time to evacuate should consider remaining evacuated.
An Evacuation Warning means the immediate threat has ended but the potential for an emergency remains and therefore residents must remain prepared for the possibility of an Evacuation Order.
The decision to reduce the Immediate Evacuation Order to an Evacuation Warning is based on a number of factors, including:
• Lower lake levels: With the rate of release through the primary spillway remaining at 100,000 cfs, over the last two days the lake level has dropped 12 feet below the top of the auxiliary spillway and no longer has water flowing over the top. This mitigation work will reduce the risk of erosion should the emergency spillway have to be used again, although flow through the primary spillway will continue to attempt to lower the reservoir to 851 feet (approximately 50 feet below full).
• Further inspections: With the water level reduced, geologists and dam safety engineering specialists from the Department of Water Resources (DWR), the Federal Energy Regulatory Commission (FERC) and the United States Army Corps of Engineers were able to inspect the damage. That inspection revealed that the integrity of the emergency spillway was not compromised by the erosion.
• Ongoing work to shore-up emergency spillway: To prevent further erosion the DWR is lining the front of the spillway with boulders and concrete. That work is expected to be completed tomorrow, ahead of the forecasted stormy weather.
• Updated weather forecasts: The decision has taken into account updated weather forecasts. The storm expected later this week is forecasted to be colder, with less rain and therefore a lower level of water flow into the reservoir than last week.
An evacuation center will remain open at the Silver Dollar Fairgrounds. All other evacuation centers supported by Butte County will be closed. Residents from other centers who are still seeking shelter due to the Evacuation Warning can go to the Silver Dollar Fairgrounds.
Residents who evacuated animals to the Silver Dollar Fairgrounds should collect their animals as soon as possible if returning home. Large animals can remain at the evacuation center, but owners are advised to secure an alternative location for animals that is outside the area under the Evacuation Warning. Owners are required to find transportation to get animals home or to an alternate location. A strict animal release protocol will be adhered to at the Silver Dollar Fairground. Animal owners must have photo ID and pink copy of the animal intake form.
Disabled residents who need assistance with transportation home should call (530) 342-0221 for para-transport. Local agencies and medical facilities are determining when patients can be returned to evacuated hospitals and skilled nursing facilities.
Sheriff Kory Honea would like to thank those members of the community who were affected by this evacuation for their cooperation and patience. It was a difficult decision to order the immediate evacuation, but the need to act swiftly in the face of a potentially catastrophic incident was necessary in order to ensure public safety.
When you return home:
• Take all of your personal items and small animals with you when you leave an evacuation center.
• Drive carefully, thousands of Butte County residents evacuated and will be driving back to the Oroville, Gridley, and Biggs communities.
Residents should stay tuned to local information sources for any changes to the Evacuation Warning.
Living in California means being prepared.
The Spillway Incident Public Information Line is (530) 872-5951.
For a full list of state emergency and social media resources visit: http://www.oesnews.com/resources-for-oroville-dam-auxiliary… .