California's reservoirs will enter fall in a slightly better position than last year, but the Golden State should prepare for more dryness, extreme weather events and water quality hazards in 2023, officials say.
The latest climate forecasting update from the Department of Water Resources came Wednesday, just days before the end of the water year, which runs from Oct. 1 to Sept. 30 in California. Officials said some of the state's biggest reservoirs, including Lake Oroville and Lake Shasta, are slightly more full than they were at the same time last year, but still remain well below average.
Water managers are now preparing for a "fourth dry year," as well as more unpredictable weather and wildfires associated with climate change, DWR Assistant Deputy Director John Yarbrough said during a meeting of the California Water Commission.
"We have more storage in the reservoirs, but we're still well below average, well below where we'd like to be," Yarbrough said. What's more, "we have to prepare and expect that we're going to see things that we haven't seen before."
Part of the challenge facing the state's water managers is that climate change is making it more difficult to predict and prepare for water outcomes, Yarbrough said. During the 2022 water year, officials observed significant swings between extreme wet and extreme dry conditions, including a notably rainy October through December followed by the driest January through March on record.
Yarbrough said such variability underscores the need for conservative planning and aggressive multiagency action.
"When we look at patterns like this, it really challenges a lot of our practices for how we plan the system, for how we're going to operate for the next year," he said.
The 2022 water year also saw warmer-than-normal temperatures and drier-than-normal conditions, he said, but both metrics were slightly improved from the year prior. Lake Shasta, the state's largest reservoir, is projected to end the water year with 1.48 million acre-feet in storage — up from 1.07 million acre-feet last year.
Still, Yarbrough emphasized that California remains in serious drought. Even with improved storage, Shasta sits at about 34% of its capacity, according to The Times' drought tracker.
It's "better than last year but not good enough," he said.