Lake Oroville, an important part of California’s water supply, is looking noticeably fuller after a series of January storms.
The atmospheric rivers dumped trillions of gallons of moisture on the state, leading to widespread flooding and devastation, but also giving a healthy boost to snowpack and drought-sapped reservoirs.
Lake Oroville, the State Water Project’s largest reservoir, was at 68% capacity on Friday — up from 28% just two months earlier, according to state data. The State Water Project is a system of reservoirs, canals and dams that provide water to approximately 27 million people.
The reservoir had fallen to such dangerous lows that in 2021 officials closed the Oroville Hydroelectric Power Plant for the first time since its completion in 1967.
Shocking images that year illustrated worsening drought conditions, including exposed areas of Oroville’s soil and a clear “bathtub ring” indicating how far the water had receded.
But photos taken by Times photographers this week showed a significant improvement. Since its lowest point — a height of just 200 meters on Sept. 30, 2021 — Oroville has risen about 55 meters, reaching a height of 250 meters on Friday.
Jeanine Jones, Interstate Resources Manager for the Department of Water Resources, said in a statement that the storms “certainly contributed to reservoir storage in California after the driest three years in the state’s recorded history.”
However, it’s important to continue to maintain supplies, she said. Last year, a wet December was followed by the driest January through March on record in the state.
“Over the next two months, it’s important that we continue to see intermittent rain and snow storms to maintain an above-average pace for our precipitation totals,” Jones said. “While this has been a strong start, the key measurement will be April 1, when snow cover is typically highest. Californians must continue to use water wisely so that we can have a thriving economy, community and environment.
Jones noted that groundwater, or the state’s system of underground aquifers, recovers much more slowly from depletion and has a long way to go before it can be fully replenished.
What’s more, Southern California’s other major water supply, the Colorado River, didn’t benefit much from atmospheric river storms and is still dwindling to dangerous lows. Federal officials have ordered California and six other states dependent on that river to drastically reduce its use.
The wet start to the year “shouldn’t deprive us of the momentum to continue working on building resilience, recycling water and storing water when we have it,” said Adel Hagekhalil, general manager of the Metropolitan Water District in Southern California, to The Times last week. “We need to save as much as possible so we can conserve water to have it available when we need it.”
The state remains under a 2021 drought emergency from Governor Gavin Newsom. MWD also issued a regional drought emergency for all of Southern California in December.
Jones said the remainder of the wet season will be critical for California. The latest season forecast from the National Oceanic and Atmospheric Administration shows equal chances of wetness or drought across most of the state through April.
“Because every day that it doesn’t rain or snow during our wettest months, we dry out,” she said. “A lot of uncertainty remains over the next two months and water managers are maintaining reservoirs to hold as much water as possible while managing flood control requirements.”
Oroville can indeed get overcrowded. In 2017, heavy rainfall flooded the area and nearly flooded the Oroville Dam.