Two years later, questions about the Oroville Dam Spillway remain unanswered


Erosion damage on the bottom half of the Oroville Spillway prompted the Department of California Water Resources to reduce the outflow from the lake. Photo courtesy of the Department of California Water Resources.

Natalie Hanson

Historic Evacuation

On the morning of Feb 12, two years ago, the Oroville Dam had been brimming with overflowing rainwater for days. The surrounding county of Butte and the residents of Oroville had been watching the levels threatening to flow over the top of the dam since Feb. 7, as the spillways released huge amounts of water.

A Crisis Response

When the emergency spillway began to disintegrate on that day, the Department of Water Resources (DWR) was forced to stop releasing water from the full dam, and a crisis of how to manage the water loomed.

On Feb. 11, water had been seen spilling over the top of the dam. The hillside next to the spillway began to deteriorate, and the possibility that the integrity of the dam would fail seemed imminent.

By the afternoon, the evacuation order for the town of Oroville, and over 100,000 residents downstream in the communities of Gridley and Live Oak, was made. A historic evacuation of over 150,000 people in the area followed.

Progress and Closure

Two years later, the town of Oroville still awaits confirmation of when the repairs on the damaged spillway will be completed. In addition, the investigation of the condition of the spillway, and why disintegration occurred, continues.

Work on the damaged spillway has been reported as nearly completed, according to information released by the DWR. In November of last year, the spillway looked nearly ready for opening – however, work on the spillway has continued into this month.

When reached out for comment, the DWR would not respond about the current timeline for completion or about the amounts that have been spent. Scott Huber, the attorney in Oroville’s suit against the Department of Water Resources, also would not provide any current information on the status of the investigation or of the repairs to the spillway. Huber previously stated that repairs of the dam and spillway reveal issues with maintenance and management of resources.

Natalie Hanson can be reached at [email protected] or @NatalieH_Orion on Twitter.