Water Quality > WQ Assessments & TMDLs for WA Waters Page > Washington State's Water Quality Assessment [303(d)]

Washington State's Water Quality Assessment [303(d)]

Ecology is changing the schedule for conducting the water quality assessment and 303(d) listing process. Rather than assessing all waters every two years, Ecology is moving to assessments of marine waters and freshwaters in alternating two year cycles. The first split list will be an assessment of all marine water data received by October 15, 2009. This assessment will result in submittal of the 2010 candidate 303(d) list for marine waters to the Environmental Protection Agency (EPA). The next freshwater candidate list is scheduled for 2012.

Background

Washington's Water Quality Assessment lists the status of water quality for a particular location in one of 5 categories recommended by EPA. This Assessment represents the Integrated Report for Sections 303(d) and 305(b) of the Clean Water Act.

The 303(d) list reports on category 5 waters, the impaired waters of the state. Waters placed on Category 5 require the preparation of a plan to improve water quality by limiting pollutant loads.  "Total Maximum Daily Loads" (TMDLs) are a key tool in the work to clean up polluted waters.

• Introduction to Washington State's Water Quality Assessment
• Overview of the Water Quality Assessment
• Information on Ensuring Credible Data for Water Quality Management and the Revision to the 303(d)/305(b) Integrated Assessment Report Policy (Policy 1-11) Documents
• Information on the 2010 Water Quality Assessment
• Information on the 2008 Integrated Water Quality Assessment (305[b] report and 303[d] list)
• Historical Information on Washington State’s Water Quality Assessments, 303(d) Lists & 305(b) Reports
• Differences between the Recent 303(d) Lists
• Water Quality Assessment Categories
• View descriptions of local water quality improvement efforts:
  • Category 4b listing descriptions
  • Water Quality Improvement Projects (TMDLs)
• The 305(b) Report
• Related Links
• For more information

Join Our ListServ to receive news and information about water quality from the Department of Ecology

Back to top of page