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Study: California Drought Means Less Hydropower, More CO2 Pollution

Folsom Lake, California

Credit: California Department of Water Resources

Above: Folsom Lake, California

Study: California Drought Means Less Hydropower, More CO2 Pollution


Peter Gleick, president, Pacific Institute


A new report shows reduced hydroelectricity generation, due to the drought in California, has increased costs to electric ratepayers and increased greenhouse gas pollution.

"The four-year drought in California has had harsh economic and environmental impacts," said Peter Gleick, president of the Pacific Institute and the report’s author.

Gleick said the increase in electricity costs is more than $2 billion from October 2011 to September 2015.

During that time period, the additional combustion of fossil fuels for electric generation also led to a 10 percent increase in the release of carbon dioxide from California power plants.

"In a normal water year, when we have full reservoirs, and we get the rain and snow that we expect, hydropower is probably 15 to 18 percent of our electricity supply," Gleick said. "Last year in 2015 it was down to around 7 percent."

Gleick said it's not just water and electricity users paying the price for reduced hydropower in California.

"The impacts of the California drought — which is the driest and the hottest in 120 years of instrumental records and one of the worst in history — has had widespread impacts on all water users, including farmers, industries, cities, and natural ecosystems," Gleick said. "And in fact, all California ratepayers are affected by the drought as they pay for electricity that is both dirtier and more expensive than in non-drought years."

The report does not project 2016 to show much improvement.

"As of early 2016, the drought continues: reservoir levels remain abnormally low, precipitation and especially Sierra Nevada snowpack are marginally above normal, and hydrogeneration is expected to continue to be below average until reservoirs refill," the report said.

"Thus, we expect costs to California ratepayers and to the environment will continue to mount."

"We're still in a hole, we're still in a big hole," Gleick said. "And unless we get a lot more rain and a lot more snow in the next month and a half or two months, I think we can expect to see hydropower below normal this year as well."

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