Water Quality Monitoring

Public Works | Natural Resources Division

The Skagit County Monitoring Program (SCMP) monitors the health of freshwater streams, rivers, and sloughs across the county by collecting water quality data.

The major goals of the SCMP are to:

Determine current stream health
Analyze long term trends
Support other water quality projects

We started this program in 2003 and now have over two decades of data. This data is an invaluable resource to understand how our local waters are changing and acts as a baseline for future generations.

Ambient Sites

We monitor 40 long-term or ambient sampling sites throughout Skagit County, spanning from Hamilton to the Swinomish Channel. Sites are visited every other week.

The County started the SCMP to determine the success of water protection rules in agricultural areas. Because of this, many sites are located in or around agricultural zoning. We chose other sites to support water clean-up efforts in Skagit County.

Sampling Methods

We measure multiple water quality parameters to assess the health of a waterway. On a bi-weekly basis we test for basic water quality parameters including temperature, dissolved oxygen, conductivity, salinity, pH, and turbidity. We also collect samples to measure two types of bacteria: fecal coliform and E. coli. On a quarterly basis we collect nutrient samples that are tested for various forms of nitrogen and phosphorus.

For more information on our sampling methods and background on the program, please check out our Quality Assurance Project Plan (QAPP) (pdf) and the SCMP Background and Methods document (pdf).