A section of the upper reservoir's dam wall was overtopped, the pumps continued to run, and the section failed, releasing a billion gallons of water in 12 minutes. The flow washed away the forest and soil down to the bedrock. One home was destroyed and its occupants injured, though thankfully there were no deaths.
The failure had several causes, but the most infamous one is that the failsafe gauge had been moved above the top of the dam wall to avoid false positives.
The reservoir was repaired and as far as I know continues to operate. I backpacked in the area several times and the dam wall has a striking appearance on the horizon.
You used to be able to go up the "mountain" and stand on the wall and look out over the water. Unfortunately, when they rebuilt it, they put gates at the road right off the highway.
A section of the upper reservoir's dam wall was overtopped, the pumps continued to run, and the section failed, releasing a billion gallons of water in 12 minutes. The flow washed away the forest and soil down to the bedrock. One home was destroyed and its occupants injured, though thankfully there were no deaths.
The failure had several causes, but the most infamous one is that the failsafe gauge had been moved above the top of the dam wall to avoid false positives.
The reservoir was repaired and as far as I know continues to operate. I backpacked in the area several times and the dam wall has a striking appearance on the horizon.