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Water Quality Standards Handbook

The Water Quality Standards Handbook is a compilation of EPA's water quality standards (WQS) program guidance including recommendations for states, authorized tribes, and territories in reviewing, revising, and implementing WQS. The guidance in this handbook supports EPA’s WQS regulations at 40 CFR Part 131.

The Water Quality Standards Handbook was first issued in 1983 and provided a compilation of EPA's WQS guidance to-date.

In 1994, The Water Quality Standards Handbook: Second Edition was issued and retained all of the guidance in the 1983 handbook unless such guidance was specifically revised in subsequent years. The 1994 handbook also contained new EPA guidance that was developed between 1983 and 1994.

In 2007, EPA updated the online version of the handbook to provide links to additional information and resources that EPA developed subsequent to 1994 in an “Updated Information” box.  In 2012, EPA revised the “Updated information” boxes to reflect any additional EPA guidance since 2007.  EPA did not revise the text of the chapters in either 2007 or 2012.

In 2014, EPA updated the text of the online versions of Chapters 1, 5, 6, and 7 to reflect current EPA guidance, and incorporated the information from the “Updated Information” boxes.  EPA also streamlined the text of these chapters to make the document more user friendly.

In November 2017, EPA published an update to Chapter 3 of its Water Quality Standards (WQS) Handbook. Chapter 3 contains information relevant to water quality criteria.

For any questions related to the guidance in this Handbook, please contact us. Copies of any referenced document can be obtained by clicking on the hyperlink or visiting the Reference Library of Water Quality Standards Policy and Guidance Documents page.

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Use the Handbook

Citing the EPA’s Online WQS Handbook

This is one way to cite/reference the EPA’s online WQS Handbook:


Government Agency (Year published). Document title. Publication number. Government Agency Office and Location. Accessed [date]. Retrieved from


U.S. Environmental Protection Agency (EPA). 2017. Water Quality Standards Handbook: Chapter 3: Water Quality Criteria. EPA-823-B-17-001. EPA Office of Water, Office of Science and Technology, Washington, DC. Accessed November 2018.

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Handbook Appendices and Other Information

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