The easing of California’s drought has boosted the state’s early spring hydropower generation to its highest level since 2011, helping it to recover from a 15-year low reached last year. But hydroelectricity production is not expected to improve much overall this year, according to the U.S. Energy Information Administration.

The West’s four-year drought desiccated many reservoirs in California, the nation’s fourth largest hydropower producer, reducing their ability to generate electricity and forcing the state to rely on other renewables and more fossil fuels for its power supply.