Testing your water quality

The only way to know for sure if your drinking water is safe is to test it. Large water systems are required to test their water often and must report out and fix the issues as soon as they are noticed. Private well and Group B users are responsible for testing their own water. While drinking water may be sampled for a wide variety of germs and chemicals, we recommended people on Group B and private water systems test for bacteria and nitrate at least once per year.

Water quality samples should be submitted to and analyzed by a state accredited lab. Once you have selected a lab, lab staff can answer questions and tell you how to collect samples. To find an accredited lab, use the WA State Dept. of Ecology Lab Search tool. To Learn more about testing your drinking water quality, visit the CDC's Guidance for Water Quality Testing and the WA State Dept. of Health's Coliform Sampling Procedure (PDF).