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Water Quality Assessment Approved

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The Washington State Department of Ecology is pleased to announce that the Water Quality Assessment submitted to EPA on September 28, 2015 has been approved by the Environmental Protection Agency (EPA). This Assessment updates freshwater listings based on water quality data meeting the state’s credible data requirements. Prior to submitting this assessment to EPA, it went through a public review and comment period. The Assessment fulfills Washington State’s obligation under the federal Clean Water Act to identify polluted waters (known as the 303(d) list) as well as report on the status of water quality statewide where data is available.

The incorporation of the National Hydrography Dataset (NHD) into the updated Assessment results in a change to the extent of river and stream reaches for which data is assessed. This new system of defining stream and river reaches helps us be consistent with other agencies and states and was strongly recommended by EPA.

With this updated Assessment, Ecology is also releasing an enhanced mapping application called the Water Quality Atlas. The Water Quality Atlas is an interactive search and mapping tool that now includes additional layers of information never before available to the public. Users can now see not only the Water Quality Assessment category results by geographic location, but can also view the associated water quality standards for a location, areas covered by Total Maximum Daily Loads (TMDLs), and nearby permitted wastewater discharge outfalls.

Information on the updated Water Quality Assessment, including access to the new search and map tools, can be found on Ecology’s website at: For questions or further information contact Patrick Lizon at 360-407-6782;

Ecology has already started the next Water Quality Assessment, which will update both marine and freshwater listings. The formal call for data period for the next Assessment was occurred from January 21st, 2016 to June 30th, 2016. Ecology also conducted a 60-day scoping period to solicit comments on the agency policy (Policy 1-11) which describes how data and information will be assessed in the next Water Quality Assessment. Ecology will soon conduct a public process to address Policy 1-11 revisions. An open invitation to participate in this process will be sent out via the water quality listserv in the near future.

Washington State University