Posts tagged: snowpack

Record-setting dry spell impacts California hydropower

Water content in California snowpack is only 17 percent of normal according to the California Department of Water Resources’ May 2 release (pdf). This means there will be a below average water supply this summer, which also impacts hydropower production for Western’s Sierra Nevada Region.

The water year, which began in October, started with some positive precipitation for the Central Valley Project. However California’s record-setting “dry” conditions in January, February and March have reduced the  hydro conditions outlook for 2013.

See the most recent hydro conditions report for April 2013 (pdf).

California releases results from fifth and final snowpack survey

The California Department of Water Resources announced the results from its fifth and final snowpack survey May 1. The survey confirmed the snowpack’s low water content, which will affect water and power deliveries in California this year.

Overall, the average water content of California’s snowpack was 40 percent of normal. The relative composition of the Sierra Nevada snowpack, from which Western’s Central Valley Project relies on to fill reservoirs and generate hydropower, was 70 percent of normal for the northern Sierras, 35 percent of normal for the central Sierras and 20 percent of normal for the southern Sierras.

Last year’s snowpack water content state-wide was 190 percent of normal by this time, which will reduce the impact of the scarce snowpack this year.

“The impact of a below-normal water year has been somewhat mitigated by above-average reservoir storage levels due to unusually wet conditions during the 2010-2011 operating season,” said Sierra Nevada Power Marketer Sonja Anderson.

However, operators of both the state and Federal water projects have already announced reduced water and power deliveries for the upcoming year, including from Western’s Central Valley Project.

California releases results from snowpack survey

The California Department of Water Resources announced the results from the third of five surveys confirming the impacts associated with the continuing dry winter conditions.

Overall, the average water content of California’s snowpack was 26 percent of the expected April 1 normal and continued to remain significantly below normal. The relative composition of the Sierra Nevada snowpack was 28 percent of April 1 normal for the northern Sierras, 26 percent of the April 1 normal for the central Sierras, and 33 percent of the April 1 normal for the southern Sierras.

During normal water conditions, January and Feb. are usually wet. However, the dearth of winter storms has caused state and Federal water managers to announce that projected water deliveries for the upcoming water year will be substantially below normal contract maximums. Although March affords an opportunity for chance for more precipitation, both the state and Federal water projects have announced reduced deliveries for the upcoming water year.

The reduced water deliveries are expected to result in reduced hydropower generation output for the Central Valley and State Water Projects. The impact of reduced water deliveries are, however, somewhat mitigated by last year’s above-normal precipitation which resulted in higher-than- average starting reservoir storage levels.