US Energy Information Agency released data on the effect of the California drought on energy production.

California drought leads to less hydropower, increased natural gas generation

Source: U.S. Department of Agriculture Drought Monitor; National Drought Mitigation Center

The drought in California continues to increase in severity since California's governor declared a state of drought emergency in January 2014. As of September 30, 58% of the state was classified as experiencing exceptional drought, the most intense drought category. These dry conditions limit hydropower generation, requiring generation from other sources to make up for the shortfall.

Bad news is Hydropower has decreased due to the drought from 20% to 10%.

California's drought, which began in 2011, has resulted in a significant decline in hydropower generation. On average, hydropower accounted for 20% of California's in-state generation during the first six months of each year from 2004 to 2013. During the first half of 2014, however, hydropower accounted for only 10% of California's total generation. Monthly hydropower generation in 2014 has fallen well below the 10-year range for each individual month.

Good news is Wind and Solar grew to be bigger than hydropower.

California's drought, which began in 2011, has resulted in a significant decline in hydropower generation. On average, hydropower accounted for 20% of California's in-state generation during the first six months of each year from 2004 to 2013. During the first half of 2014, however, hydropower accounted for only 10% of California's total generation. Monthly hydropower generation in 2014 has fallen well below the 10-year range for each individual month.

In the below graph you can see the % of power coming from the various sources.