Snow Survey Shows Sierra Is High and Dry
Water agencies expected gloomy results from the season’s last snow survey, and those worries were realized May 2 with the Department of Water Resources reporting California’s snowpack water content is only 17% of normal for the date.
Manual snow readings taken Thursday by DWR near Echo Summit were: Lyons Creek (6,700 feet) with 3.3 inches of water content, 15% of average; Phillips Station (6,800 feet) with no snow; and Alpha (7,600 feet) with 1.2 inches of water content, only 5% of normal.
Electronic readings gathered around the state showed water content in the northern mountains is 16% of normal for the date, the central Sierra is at 23% and the southern Sierra is at 9%.
In addition, beginning in April a new collaboration between DWR and NASA’s Jet Propulsion Laboratory began mapping the Sierra snowpack from the sky. A Twin Otter aircraft carrying NASA's Airborne Snow Observatory took weekly flights over the Tuolumne River Basin. The system’s lasers and spectrometers measure snowpack volume and snow melt. NASA plans to expand the airborne mapping program to the entire Sierra Nevada and Upper Colorado River Basin.
Despite the dry conditions reported Thursday, the state’s major reservoirs remain near or above average levels, with the exception of San Luis Reservoir, which is at 59% of average in part due to Delta pumping restrictions enacted earlier this year to protect smelt. The wet November and December filled the state’s reservoirs, but the historically dry January through March took a big toll on snowpack.
“Reservoir storage will meet much of the state’s water demand this year, but successive dry years would create drought conditions in some areas,” DWR state in a news announcement Thursday.
DWR currently projects it will only be able to deliver 35% of requested amounts from the State Water Project. Central Valley Project allocations currently are at 20% for agricultural water service contractors south of the Delta, and are at 70% of historical use for CVP municipal and industrial water service contractors south of the Delta.
In response to the latest snow survey readings, DWR Director Mark Cowin and others reiterated that continued commitment to the Bay Delta Conservation Plan would help solve conflicts between water deliveries and pumping restrictions aimed at protecting fisheries.
“The low snowpack measurements reinforce how important it is for our state’s water delivery system to be flexible enough to take advantage of extremely wet times so we can prepare for these dry spells,” said Terry Erlewine, general manager of the State Water Contractors.