Snow data recently compiled by survey teams from the Lassen National Forest is now available to the public.
Snow surveys are conducted during the first few months of the year to determine the water content in the accumulated snowfall. The information is collected for the State of California and used for stream flow forecasting to help determine how much water will be available for beneficial uses such as irrigation, fishing, range management, domestic water, and electric power generation, according to Forest Hydrologist Carol Thornton.
As Thornton explained, California is in its third year of drought, with the winter of 2013-2014 having the least amount of rain and snow of the last three years. Rainfall and the snowpack have been low across the state. As of April 1, the state average for rainfall was 50% compared to 75% last year. The snowpack water content is 25% of average so far for this water year (Oct.1, 2013 – Sept. 30, 2014) compared with 40% last water year.
Watersheds that flow into the Sacramento River, including the Feather and Pit rivers, averaged 55% of average for precipitation and had snowpack water content at only 20% of average. The North Lahontan hydrologic region, which includes the Susan River, has had precipitation of 60% of average, with snowpack water content at 25% of average.
The following website provides information on surveys taken throughout California:
http://cdec.water.ca.gov/cgi-progs/snowsurvey_sno/COURSES. For local information, look for the river basins and their courses associated with snow survey data collected at locations around the Lassen National Forest, as follows:
- Feather River Basin – Fredonyer Pass 3/Course 387; and Chester Flat/Course 61
- Pit River Basin – Blacks Mountain/Course 31; Thousand Lakes Wilderness/Course 33; Snow Mountain/Course 34; McElroy Pass/Course 37; Burney Springs/Course 41
- Susan River Basin – Silver Lake Meadows/Course 45; and Norvell Flat/Course 46
Increasing demands on water use means accurate forecasting is very important. The low snowpack and low precipitation combined with the past two years of drought means reservoir levels are low and are expected to continue to drop this summer. Many rivers and springs on the Lassen National Forest have lower spring flows due to lack of runoff, concluded Thornton.
