In the wake of the damage occurring to the two spillways at Oroville Dam, crews are working to widen the channel at the base of the main spillway, with the goal of bringing the 645-MW Hyatt Power Plant back into operation at full capacity.
One turbine-generator unit was restarted March 5, but debris needs to be removed before the remainder can begin operating. The California Department of Water Resources says as of the morning of March 6, 427,000 cubic yards of the estimated 1.7 million cubic yards of debris had been removed.
DWR says that having the power plant fully operational will allow the release of 13,000 cubic feet per second of water to help manage reservoir inflows and outflows due to spring runoff. As of March 6, the lake level was 855.3 feet elevation and inflows were ranging from 15,000 to 20,000 cfs. DWR says it does not expect Lake Oroville to rise above 860 feet elevation while the spillway flows are halted.
To meet environmental requirements, DWR is releasing water through the Thermalito Diversion Dam and Thermalito Afterbay River Outlet, with total flow to the Feather River remaining at 2,500 cfs.
Other issues being faced include fish stranding as water recedes and collapse of the banks of the Feather River.
For example, The Mercury News reported that fish were being stranded in pools as water levels dropped, and California DWR and personnel with the Department of Fish and Wildlife deployed to rescue stranded fish, identified using helicopter surveys.
In addition, the San Francisco Chronicle reported that miles of riverbank have “come crashing down,” particularly around Yuba City. The resulting damage has been reported to include downed trees, collapsed bluffs, and damage to rural roads and irrigation lines.
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