Snow Survey, Water Supply Forecasting, and Drought Monitoring

Conserving and managing scarce water supplies is a priority in many parts of the country.

In the West, most of the available water comes from melting mountain snowpack. Irrigation water management is critical to achieving the most efficient use of this valuable and limited resource. NRCS continuously monitors mountain snowpack and climate using the 650 station SNOTEL (SNOwpack TELemetry) network to forecast water supplies.

Monitoring soil moisture and assessing drought risk are NRCS activities supported by using climate information collected by the expanding NRCS SCAN (Soil Climate Analysis Network) comprised of 49 stations in 32 states.

A full spectrum of water and climate information is available from the National Water and Climate Center, including near real-time SNOTEL and SCAN climate information, water supply forecasts, state climate maps, historical digital datasets, and climate summaries.

Major sectors of the economy — agriculture, industry, recreation, and government — base their water management plans on NRCS water supply forecasts, climate products, and drought risk assessments.

NRCS snow surveyors measure mountain snowpack and forecast seasonal runoff in streams and rivers. This information is used to make sound water management decisions.

Snow Survey School Teaches Sampling — and Survival

Each year, USDA's Natural Resources Conservation Service conducts a snow survey school to train snow surveyors, with a curriculum combining sampling and survival.

"Accurate snow sampling sometimes needs to be done in some pretty remote locations," says school coordinator Garry Schaefer of NRCS. "It is rare, but occasionally snow samplers get caught in the elements and have to hole in and wait for help. It's a possibility we must recognize and prepare for."

Some 30 scientists, engineers, and technicians from 12 western states were trained in such skills as snow sampling, avalanche recognition, and outdoor emergency care at the school held in Tahoe City, California, in January 2001.

The training included an overnight snow bivouac when each of the 30 participants were required to ski to a typical sampling site, build a habitable snow hut, and spend the night in it.

The snow survey school is part of a cooperative effort to forecast water supplies based on snowpack and other hydrometerologic conditions. The school is conducted by USDA's Natural Resources Conservation Service, which heads the National Cooperative Snow Survey and water supply forecasting program in the 12 western states. The exception is in California, where the state's Department of Water Resources heads the program.

The manual data collection is complemented by more than 600 automated SNOTEL stations to make modern water supply forecasts in the West. The automated stations monitor precipitation data and make it available on a daily basis to those who model stream flow and forecast water availability.

Additional Information

• Snow Survey, Water Supply Forecasting Program
• National Water and Climate Center
• Water Supply Forecasts
• Snotel Data by State