Snow Water Supply Forecasting Program

Snow plays an important role in water supplies in most Reclamation watersheds. Snow in mountain watersheds acts as a natural reservoir, holding the frozen water that gradually melts to release flows as the season progresses. Understanding snow conditions is critical for water supply forecasts relied upon by reservoir operations and broader water management in the Western United States. This, coupled with impact of climate change on historical precipitation and snow accumulation/melt patterns, underscores the critical importance of snow monitoring for water managers and water users alike.

Activities to monitor snow and other basin conditions have expanded to cover more areas and technological advancements have made these measurements more precise. Snow monitoring informs a host of forecasts ranging from short-term streamflow to seasonal water supply forecasts, and advancements in monitoring can lead to forecast benefits. However, uncertainty about snow conditions as well as timing and magnitude of snowmelt runoff remains. The variable nature of snow itself and the extreme cold that often accompanies snow can pose challenges for effective, reliable snow monitoring. Snow measurement can be conducted from different platforms, ranging from ground-based to aircraft and satellite based, or estimated using modeling tools. Each platform and each specific snow monitoring technology has tradeoffs between cost, spatial coverage, temporal coverage, accuracy, precision, resolution, geographic suitability, and reliability.

Program Objectives

The Snow Water Supply Forecasting Program aims to enhance snow monitoring and subsequent water supply forecasts to the benefit of water management. This program supports the following objectives through external grants and collaboration with partners:

  • Demonstrating and/or deploying emerging snow monitoring technologies.
  • Demonstrating and/or deploying to existing snow monitoring technologies.
  • Deploying existing snow monitoring technologies in underserved areas.
  • Improving the use of snow monitoring data to enhance the skill of water supply forecasts.

Program Authority

The Snow Water Supply Forecasting Program Authorization Act, 2020, establishes the Snow Water Supply Forecasting Program within the Department of the Interior (DOI). The Bureau of Reclamation, acting on behalf of the Secretary, is implementing the Program to advance emerging technologies to enhance snow monitoring and subsequent water supply forecasts. Program activities stand to build climate change resilience by enabling improved water management and will be implemented consistent with Executive Order (EO) 14008: Tackling the Climate Crisis at Home and Abroad.

Last Updated: 3/21/23