Washington State Water Quality Assessment 305(b) Report

Section 305(b) of the federal Clean Water Act (CWA) requires each state to prepare a report on the current statewide status of water quality every two years. This evaluation is called the Section 305(b) report. It identifies the water quality status of all waterbodies in the state for which sufficient credible data is available. The Environmental Protection Agency (EPA) compiles the information from the states’ 305(b) reports and prepares a summary for the U.S. Congress on the status of the nation’s waters.

The 303(d) list is related to the 305(b) report in that it identifies waterbodies for which there is evidence that water quality has become degraded relative to the natural conditions and state water quality standards. In other words, the 303(d) list is a subset of the waterbodies evaluated in the 305(b) report, but is a separate CWA requirement that states must fulfill.

Since 2000, EPA recommended that states combine the 305(b) report and 303(d) list into a single “Integrated Report.” The most recent integrated report guidance can be found on EPA’s website at: www.epa.gov/tmdl/integrated-reporting-guidance.

The state of Washington no longer publishes a separate 305(b) report and 303(d) list. These two components of Washington’s water quality assessment are combined into a single searchable database. The water quality status history for each assessed waterbody is available in the most recent EPA-approved Integrated Report through the Water Quality Assessment database search tool.


Past 305(b) Reports:

If you have questions about the Section 305(b) Report, please contact Patrick Lizon at 360-407-6782 or by e-mail at: 303d@ecy.wa.gov.







Last updated December 2015