Skip to main content
U.S. flag

An official website of the United States government

Here’s how you know

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

HTTPS

Secure .gov websites use HTTPS
A lock (LockA locked padlock) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

    • Environmental Topics
    • Air
    • Bed Bugs
    • Chemicals and Toxics
    • Climate Change
    • Emergency Response
    • Environmental Information by Location
    • Environmental Justice
    • Greener Living
    • Health
    • Land, Waste, and Cleanup
    • Lead
    • Mold
    • Pesticides
    • Radon
    • Science Topics
    • Water Topics
    • A-Z Topic Index
    • Laws & Regulations
    • By Business Sector
    • By Topic
    • Compliance
    • Enforcement
    • Guidance
    • Laws and Executive Orders
    • Regulations
    • Report a Violation
    • Environmental Violations
    • Fraud, Waste or Abuse
    • About EPA
    • Our Mission and What We Do
    • EPA Administrator
    • Headquarters Offices
    • Regional Offices
    • Labs and Research Centers
    • Planning, Budget, and Results
    • Organization Chart
    • EPA History
    • Staff Directory
Contact Us

Clean Water Act Analytical Methods

  • Draft Method 1633 for PFAS

    • Draft Method 1633
  • Frequent Questions about PFAS Methods for NPDES Permits

    • New FAQs concerning Draft Method 1633 for PFAS

EPA publishes laboratory analytical methods (test procedures) that are used by industries and municipalities to analyze the chemical, physical and biological components of wastewater and other environmental samples required by the Clean Water Act.

Current and Recent Actions

  • 3rd Draft Method 1633 for PFAS
  • Frequent Questions about PFAS Methods for NPDES Permits
  • Methods for 2,3,7,8-substituted PCDDs/PCDFs
  • Draft Method 1621 for Adsorbable Organic Fluorine
  • Methods Update Rule - 2023 Proposal
  • PCB Congeners by Low-Resolution GC-MS - Method 1628
  • Coliphage Methods 1642 & 1643
  • MDL Frequently Asked Questions

Approved CWA Methods

  • Chemical
  • Microbiological
  • Whole Effluent Toxicity
  • Radiochemical
  • Industry-Specific
  • Frequent Questions

Other CWA Methods

Optional methods for analyzing wastewater and biosolids (not approved under 40 CFR Part 136):
  • Chemical
  • Microbiological
    including MST Methods 1696 & 1697
  • Biosolids

Alternate Test Procedures

Development of modified EPA methods or new methods
  • ATP Overview
  • Protocol Documents
  • ATP Questions and Answers
  • How to Get Methods Approved

Regulations and Support Documents

  • Regulatory History for:
    • Methods Update Rules
    • Microbiological methods
    • Oil & grease
    • Cyanide
    • Dioxins & furans
    • Mercury and chromium-VI
  • Other methods support documents
  • Toxic and Priority Pollutant lists
  • Legal authority for methods

Related EPA Programs

  • NPDES permit program
  • Effluent Guidelines program
  • Other EPA method collections
    Including drinking water, air and solid waste methods
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on February 22, 2023
United States Environmental Protection Agency

Discover.

  • Accessibility Statement
  • Budget & Performance
  • Contracting
  • EPA www Web Snapshot
  • Grants
  • No FEAR Act Data
  • Plain Writing
  • Privacy
  • Privacy and Security Notice

Connect.

  • Data.gov
  • Inspector General
  • Jobs
  • Newsroom
  • Open Government
  • Regulations.gov
  • Subscribe
  • USA.gov
  • White House

Ask.

  • Contact EPA
  • EPA Disclaimers
  • Hotlines
  • FOIA Requests
  • Frequent Questions

Follow.