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Impaired Waters and TMDLs

Reports and Resources about Impaired Waters and TMDLs

The Process

The Clean Water Act "Impaired Waters Restoration Pipeline"

The TMDL Program Results Analysis Project: Matching Results Measures with Program Expectations


Introduction to Clean Water Act Section 303(d) Impaired Waters Lists (PDF)

Integrated Reporting (IR) – Improved Reporting for CWA Sections 303(d), 305(b), and 314 (PDF)

303(d) Listed Impaired Waters State, Watershed and National Geospatial Data

Dataset: Section 303(d) Listed Impaired Waters State or Watershed-level, Geographic Information Systems (GIS) Data Downloads

The Impaired Waters with TMDLs National Geospatial Dataset (PDF)

Dataset: Impaired Waters with Total Maximum Daily Loads (TMDL) Geospatial Dataset


Total Maximum Daily Loads (TMDL) Progress (PDF)

Developing Effective TMDLs: An Evaluation of the TMDL Process

Developing Effective Nonpoint Source TMDLs: An Evaluation of the TMDL Process

Third Party TMDL Development Toolkit

Category 4b - A Regulatory Alternative to TMDLs

Category 4b - National Status and Trends

Category 4b Demonstrations


Recovery Potential Project (PDF)

FY2010 National Report on Implementing TMDLs

Analysis of TMDL Implementation Rates in EPA Region 5 (PDF)

Sampling TMDL Implementation Rates and Patterns in the North Central United States

TMDL Implementation: Lessons Learned

State Approaches and Needs for Measuring, Tracking and Reporting on Water Quality Improvements

A Method for Comparative Analysis of Recovery Potential in Impaired Waters Restoration Planning

Implementing Total Maximum Daily Loads: Understanding and Fostering Successful Results


Summary of EPA's "100 TMDLs Review" (PDF)

FY2010 Assessment of Improving and Recovered Waters with TMDLs

Evaluating Options for Documenting Incremental Improvement of Impaired Waters Under the TMDL Program


Applying Results Findings: The Recovery Potential Project

Section 319 Nonpoint Source Success Stories