Function & Details of Storm Water Sampling
Storm water sampling involves regular testing of the quality of the storm water that is generated and discharged in San Juan County. storm water carries contaminates from surfaces that it contacts. Just as we might use a hose to wash off the deck or wash our cars rain falling on surfaces cleans those surfaces and becomes storm water runoff. What is washed off often includes contaminants that damage receiving waters. storm water sampling helps us understand what types of contaminants may be more or less common in our area as compared to the rest of the world and thus help us make better choices about how to manage the storm water.
The storm water Utility funds a sampling program throughout San Juan County. The program is carried out by staff from Washington State University and the San Juan Islands Conservation District. The program is also supported through grants from the Washington Departments of Health and Ecology.
The details regarding the sampling program are described in the storm water Monitoring Plan.
When is Sampling Conducted
Sampling is conducted shortly after or during specific types of rainfall events (qualifying events) that occur after short dry periods and are likely to produce a prescribed minimum amount of rainfall. The water is tested for bacteria, nutrients, metals, organic compounds and various pesticides.
Twenty-two freshwater and nine marine sites have been regularly sampled over the past 2 years. The results of the tests are posted on this web page along with technical memoranda that evaluate the data.