Publication Summary

The Surface Water Quality Standards for the State of Washington (Chapter 173-201A WAC) contain criteria to reduce the chance of people becoming ill from eating shellfish or from swimming or wading in natural waterbodies. The state′s current criteria for bacterial pollutants is based on the use of fecal coliform as an indicator of contamination by humans and other warm blooded animals. In 1986, the United States Environmental Protection Agency (USEPA) recommended to states that they should no longer use fecal coliform as an indicator of the bacterial health of water. Based on studies conducted by USEPA, it was recommended that states either use Escherichia coli (E. coli) or enterococci for their bacterial indicator criteria in freshwaters, and use only enterococci in marine waters. Washington, along with many other states, did not adopt the newly recommended criteria. In the summer of 1996, the Washington State Department of Ecology (Ecology) convened a technical workgroup to examine the technical merits of the state′s bacterial criteria. This report documents the technical and policy issues evaluated by the initial work-group and a later predecessor group. The information prepared with the assistance of the technical work-groups was used to focus discussions with numerous advisory panels both internal and external to Ecology.