Levels of major water supply reservoirs in California 2022

Southwestern United States is in the midst of a megadrought, which is causing crucial water resources to deplete. Shasta Lake, the largest reservoir in California, was at 31 percent of its gross capacity on December 1, 2022, at 1.4 million acre feet (AF). This was roughly 57 percent of the historical average for this date. Meanwhile, Lake Oroville, the states second-largest reservoir, was at 55 percent of its average capacity. Lake Oroville provides water to almost 30 million Californians.

California is not the only U.S. state where water resources have dropped to critically low levels due to severe droughts. In Nevada, water levels in Lake Mead have been dropping to historic lows in recent years, and in July 2022 were at the lowest monthly levels recorded since the 1930s.