Oroville Dam: Residents return home despite threat of new storm
- Author: Larry Hoffman Feb 16, 2017,
Feb 16, 2017, 1:46
For some here, the beginning of re-entry into normalcy won't come back for a while, at least not while work on the Oroville Dam's emergency spillway continues, the main spillway is still nowhere near ideal and more rain is expected soon. The crack is believed to have Local authorities replied with a mass evacuation over three counties in Northern California. Concern over apparent erosion on the emergency spillway after it activated over the weekend led officials to evacuate nearly 200,000 people downstream from the lake Sunday night.
The department said water is now flowing through the main spillway at 100,000 cubic feet per second, lowering Lake Oroville's level by 3 to 4 inches per hour.
A view of Oroville Dam as lake levels recede from 901 feet on February 12. It's not clear how damage to the two spillways will affect long-term water releases from the dam. Gov.
The Department of Water Resources estimated fix costs last week at $100 million. The goal is to get it to 850 feet before storms hit later this week. As of Wednesday morning, it was at 878 feet and emptying at about 19 feet per day, which Croyle called a "significant improvement" - it had been draining at less than half that rate.
The spillway yesterday looked like a waterfall as roaring water dropped hundreds of feet before crashing into the sinkhole, causing a wet eruption and spraying a mist on onlookers hundreds of feet away.
Crews have been working around the clock to bolster a weakened area beneath an emergency spillway that forced 188,000 residents to flee their homes on Sunday in an emergency evacuation.
L.A. County has experienced catastrophic dam collapses in the past.
The plan is to cover much of the reinforced hillside with slurry, further reducing the risk of erosion.
However, once the rain starts, those efforts will have to stop.
There have been concerns about Oroville Dam safety since the erosion of the primary spillway was discovered a week ago.
But first, the spillways have to handle inflows from a series of upcoming storms. About 11% is in an abnormally dry period, 36% is in moderate drought, 10% is in severe drought and 1% is in extreme drought, after massive rain and snow storms drenched the state over the last month. Still, Croyle said the spillway has been repaired, and he's confident it could be used if needed.