An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Clean Water Act Analytical Methods

Methods Update Rule - 2017

Rule Summary

""EPA promulgated changes in 2017 to analytical test procedures that are used by industries and municipalities to analyze the chemical, physical, and biological components of wastewater and other environmental samples that are required by regulations under the Clean Water Act.

The changes include revised methods published by EPA and voluntary consensus standard bodiesHelpvoluntary consensus standard bodiesDomestic or international organizations that plan, develop, establish, or coordinate voluntary consensus standards using agreed-upon procedures. These bodies are defined by openness, balance of interest, due process, the existence of an appeals process, and a consensus process., such as ASTM International and the Standard Methods Committee. EPA added certain methods reviewed under the alternate test procedures (ATP) program to 40 CFR Part 136 and clarified the procedures for Agency approval of nationwide and limited use ATPs. Further, EPA revised the procedure for determination of the method detection limit (MDL).

These revisions:

Final Rule

Documents related to this rulemaking can be found on EPA’s docket at The Docket Number is EPA-HQ-OW-2014–0797.

Background Information

Additional Information

For further information on the final rule, please contact Adrian Hanley ( or 202-564-1564.