Water supply monitoring

Rivers and streams are an important part of the state's water supply. These online tools track flow levels:

• Freshwater DataStream – current and historical continuous data for rivers and streams  
  • Instream Flow Data – includes USGS gage (control points) identified in rule

• U.S. Geological Survey – Look at daily streamflow data for Washington state
• Northwest River Forecast Center – View river volume forecasts for the coming year

• Natural Resources Conservation Services (NRCS)
  • Predefined maps - links to snowpack maps and data
  • Current Snow Water Equivalent (SWE) % of Normal - Basin summary snowpack map
  • Washington Snowpack Summary - Maps and Graphs
  • Washington SNOTEL - Map of Current Snow Water Equivalent (SWE) % of Normal
•  National Weather Service
  • Regional Snow Analysis

Rain, lowland snow, and other precipitation are important contributors to water supply. Find maps and measurements of this precipitation below:

• Natural Resources Conservation Services (NRCS)
  • Predefined maps - links to precipitation maps and data
• Community Collaborative Rain, Hail and Snow Network - Citizens provide these weather measurements

Groundwater — water held in aquifers — is critical to the water cycle. Find the assessments of aquifers here:

• USGS: Washington Active Water Level Network
• Ecology: Statewide 2017 Groundwater Assessment:
• Ecology: Groundwater Quality Assessment