Watershed health monitoring

Since 2009, we've been collecting data on overall river and stream health to answer questions about the condition of Washington’s watersheds. We follow strict measurement, quality-control, data-management, review, and validation procedures to gain an accurate picture of watershed health.

Our study

The Watershed Health Monitoring project tracks the status of Washington's rivers and streams using a statewide data collection effort. Over 80 sites are visited between July 1 and Oct. 15 to complete biological, chemical, and physical assessments. To learn more about annual sampling, visit our other pages:

  • The Regional reports webpage presents preliminary data for all eight Status and Trends Regions over two to three rounds of sampling per region. Find out how your stream fared.
  • Sampling schedules details the monitoring-sites rotation, sample design, and contains the latest candidate site list.
  • Sampling sites explains the difference between random and reference sites and shows where we have already sampled.

The data we collect at these sites help us statistically represent Washington and allow us to show broad trends throughout the state.

Methods and data

In addition to our sampling, we help other researchers with tools to objectively assess watershed health. These include standard protocols for monitoring rivers and streams, protocol trainings, the Washington Master Sample site set, and the WHM Search database for securely managing stream-habitat data.


Our dataset is publicly available to help support other studies as well.  Below are reports that have used Watershed Health Monitoring data: