Watershed health studies

We collect biological, habitat, water, and sediment chemistry data from stream sites across the state, evaluating multiple aquatic communities to assess river and stream health through time, growing human influence and a changing cliamte. State and local agencies use our data to protect and improve the condition of Washington's surface waters.

Methods and protocols

View or download our dictionary of data metrics and quality assurance project plans, which provide details about our study and metrics we use. To request our standard operating procedures, please contact our science lead listed on this page.

Dictionary of Metrics for Physical Habitat: Definitions and Calculations Used for Watershed Health Monitoring and Related Studies is the data dictionary for habitat metrics in the EIM database.
Status and Trends Monitoring for Watershed Health and Salmon Recovery: Quality Assurance Monitoring Plan describes our study for sampling watersheds in salmon recovery regions.
Quality Assurance Monitoring Plan: Ambient Biological Monitoring in Rivers and Streams: Benthic Macroinvertebrates and Periphyton describes our study for evaluating macrinvertebrate and periphyton communities.

Modeling macroinvertebrate communities in streams

Stream-dwelling macroinvertebrates respond to changes in the physical and chemical environment, and are used as indicators of the conditions experienced at a particular site. Data are collected from sites ranging from targeted reference sites with relatively little human influence to randomly selected sites from around the state to answer two questions:

What is the state of biological conditions in streams and rivers throughout Washington?
Are things getting better or worse through time?

Our bioassessment models evaluate stream macroinvertebrate communities, or the benthic index of biological integrity (B-IBI). B-IBI is a useful tool for assessing streams in the Puget Sound basin. Puget Sound Stream Benthos has more information on this tool.

Data for the studies

Data for raw taxa counts, habitat metrics, water chemistry and physical parameters can be viewed or downloaded from the Environmental Information Management (EIM) database. Individual study datasets are linked in study details below.

We sample over 100 targeted reference sites throughout Washington every 2-3 years. These sites tell us what conditions are like at sites with minimal human impacts. Data collected includes macroinvertebrate and periphyton communities, physical habitat characteristics, chemical and physical parameters.

Data — EIM Study ID = WHM_BIO shows results for ambient biological monitoring sites.

We annually sample 16 targeted reference sites throughout Washington as baselines to spot trends. These sites also tell us what conditions are like at sites with minimal human impacts. We collect data for fish, macroinvertebrate and periphyton communities, physical habitat characteristics, and chemical and physical parameters.

Data — EIM Study ID = WHM_SEN shows results for status and trends sentinel-site monitoring.

Since 2009, we have randomly sampled over 500 sites as part of the watershed health monitoring study to provide a spatially balanced, unbiased estimate of the biological health of the state's streams and rivers. Each summer, 50 sites are sampled in one of Washington's eight Salmon Recovery Regions. Data include those for fish, macroinvertebrate and periphyton communities, physical habitat characteristics, and chemical and physical parameters.

Data — EIM Study ID = WHM_WAM0 shows results for Watershed Health Monitoring.

Reports

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

The Watershed Health Monitoring project tracks the status of Washington's rivers and streams. Each summer our researchers visit over 50 sites between July 1 and Oct. 15 to complete biological, chemical, and physical assessments. The data we collect at these sites allow us to show broad trends about the health of Washington's watersheds.

Learn more about our study and results below:

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.

State of the Salmon in Watersheds reports are updated biennially with our data.
"Improved thermal preferences and a stressor index derived from modeled stream temperatures and regional taxonomic standards for freshwater macroinvertebrates of the Pacific Northwest, USA" — published in Ecological Indicators Volume 160, March 2024, 111869.
“Strong but heterogeneous distributional responses to climate change are projected for temperate and semi-arid stream vertebrates” — published in Aquatic Conservation Volume 32, August 2022, pages 1291-1305.
“The use of multiscale stressors with biological condition assessments: A framework to advance the assessment and management of streams” — published in Ecological Indicators Volume 737, October 2020, 139699.
"The first statewide stream macroinvertebrate bioassessment in Washington State with a relative risk and attributable risk analysis for multiple stressors" — published in Ecological Indicators Volume 102, July 2019, pages 175 –185.
“Flow pulses and fine sediments degrade stream macroinvertebrate communities in King County, Washington, USA” — published in Ecological Indicators Volume 93, October 2018, pages 365-378.
“Stormwater Action Monitoring Status and Trends Study of Puget Lowland Ecoregion Streams: Evaluation of the First Year (2015) of Monitoring Data” — King County publication, May 2018.

Contact information

Edward M. Krynak
Watershed Health Monitoring Lead
edward.krynak@ecy.wa.gov
360-742-1581