Take a captivating aerial tour of California’s massive water system
As the 2018-19 precipitation year came to a close Sunday, record-setting snowpack in the Sierras and above-average rain means several reservoirs are near full capacity heading into the dry summer months. Here’s a look at the past 12 months of California water.
In May, downtown Sacramento broke a 130-year-old record for May rainfall. While May averages 0.76 inches of rain, this year saw an all-time high 3.42 inches.
Rainfall from July 1, 2018, to June 30, 2019, was 131 percent of average for Sacramento Executive Airport, and it was above average for a majority of the state, according to Golden Gate Weather Services. Irvine saw rainfall that was 135 percent of average, and Los Angeles saw rainfall that was 126 percent of average.
However, San Francisco, Salinas, Fresno, Merced and Modesto only saw between 100 and 110 percent of average.
January through March saw sustained moderate to heavy snow storms, which dropped blankets of snow throughout Northern California.
The April 1 snowpack is an important indicator of water health, and one survey station in the Sierras had its fourth-highest level ever recorded at that location. Water in California’s snowpack was above average in the final snow survey of the year in May.
In early June, the statewide Sierra snowpack was 202 percent of normal, the Department of Water Resources said, making it California’s fifth largest snowpack dating back to 1950.
Winter snowpacks are important as they end up being the state’s water supply for the rest of the year, National Weather Service meteorologist Hannah Chandler-Cooley said.
A majority of the snowpacks have melted already, given that peak snowpack melting occurs in late spring, according to Chandler-Cooley. Northern, Central, and Southern Sierra snowpacks are at 4 percent, 7 percent, and 6 percent respectively of their April 1 averages for snow-water equivalent, which is the amount of water produced if all of the snow were to melt at once.
Lake Oroville, Folsom Lake, Lake Shasta, Lake Berryessa, and Lake Camanche reservoirs were all over 100 percent of average for the month of June as of Sunday, according to the DWR.
Lake Oroville was at 98 percent capacity, Lake Shasta was at 96 percent capacity, and Folsom Lake, Berryessa, and Lake Camanche were all near 96 percent capacity.
Due to robust reservoirs, the Department of Water Resources announced in June that it would increase the 2019 State Water Project allocation from 70 to 75 percent in its final allocation for the calendar year, which is equivalent to 3,145,106 acre-feet of water. The initial allocation in November 2018 was 10 percent.
The increase in water deliveries will provide additional water supply for more than 27 million Californians and 750,000 acres of farmland, according to the release.
Correction: A previous version of this story used an incorrect term for the precipitation year.