Lake Oroville is 100% full as reservoirs are revived
California’s second-largest reservoir is now completely full after a historic rainy season recharged reservoirs across the state following years of drought.
Lake Oroville, fed by the Feather River about 80 miles north of Sacramento, is at 100% of its capacity, according to the California Department of Water Resources.
Since Dec. 1, the lake’s water level has increased more than 240 feet thanks to more than 2.5 million additional acre-feet of water brought on by a series of powerful winter storms and the melting of a historically deep snowpack. That puts the reservoir at 127% of its historical average for the date, state data show.
Scattered showers arrived Tuesday afternoon in the Sierra Nevada and areas east of Oroville, according to the National Weather Service, but dam operators at the reservoir do not expect a deluge of water or a risk of flooding downstream.
The Department of Water Resources has increased the outflow of water from the main spillway at Oroville Dam and an outlet farther south to ensure the full reservoir can hold snowmelt without overflowing. Officials noted that scattered waves could crest over the dam’s emergency spillway, which was repaired after nearly collapsing in a 2017 storm.
Tracy Pettit-polhemus, supervising engineer for the DWR’S State Water Project Operations Control Office, told the Chico Pressenterprise there is a small chance that the agency will need to step up water releases again, but there is no potential for flood risk.
Peak inflow at Lake Oroville occurred in April and is trending downward, though it could tick up at times due to a lateseason storm or increased snowmelt from a heat wave, State Water Project official John Yarbrough told news station KCRA.
It’s a far cry from the situation in 2021, when Lake Oroville was at 24% capacity and the state was pockmarked with dry lake beds after three consecutive drought years.
Farther north, Shasta
Lake — which now sits at 97% full — was at 38% of capacity in the middle of last summer, boasting an unmistakable “bathtub ring” high above the water, showing where levels at California’s largest reservoir typically reach in a healthy rain season.
In October, the U.S. Bureau of Reclamation’s Central Valley Project, which manages Shasta Lake and its outflow, reported that the water year would start with just 3.6 million acre-feet of storage water, marking one of the lowest figures in recent years.