Clean Water Act Section 303(d): Impaired Waters and Total Maximum Daily Loads (TMDLs)

Identifying Polluted Waters and Developing Plans to Restore Them

Learn about Section 303(d) of the Clean Water Act.

Section 303(d) of the Clean Water Act authorizes EPA to assist states, territories and authorized tribes in listing impaired waters and developing Total Maximum Daily Loads (TMDLs) for these waterbodies. A TMDL establishes the maximum amount of a pollutant allowed in a waterbody and serves as the starting point or planning tool for restoring water quality.

Highlights

2022 - 2032 Vision for the Clean Water Act Section 303(d) Program
Information Concerning 2022 Clean Water Act Sections 303(d), 305(b) and 314 Integrated Reporting and Listing Decisions

About the Program

Water Restoration and Protection in the U.S.
- Impaired Waters Restoration Process
- Healthy Watersheds
Program Overview
What You Can Do

Program Activities in EPA's Regions

Find Your Region
Find Impaired Waters in Your State using the Assessment and TMDL Tracking System (ATTAINS)

Working with the States

Statute and Regulations
National Coordination
Program Vision
Identifying and Listing Impaired Waters
Developing TMDLs
Alternative Restoration Plans
Protection Approaches
Technical Tools & Resources
Assessing Impacts from:

Partnerships

Working with Stakeholders
Working with Tribes