The historic drought in California and the west has slashed the region’s ability to generate hydropower as the amount of water in lakes and rivers has dropped.
California, about half of which is now in an “exceptional” drought, has 287 hydroelectric dams, whose production has dropped 60 percent in the last four years, the Washington Post reports.
{mosads}That is increasing the risks of blackouts, since hydropower, a clean power source, is flexible and can be used to fill in gaps when power demand is highest.
Some dams have shut down as the area’s snowpack, the reserve of snow in mountains that melts to provide water to areas below, has reached its lowest levels in record history, the Post said.
Hydropower is forecast this year to provide only 7 percent of California’s electricity needs, down from 23 percent in 2011.
Much of the gap is being filled in with renewable power sources like wind and solar energy, but natural gas has also increased as a fuel for electricity.