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
    • Cancer
    • Chemicals, Toxics, and Pesticide
    • Emergency Response
    • Environmental Information by Location
    • Health
    • Land, Waste, and Cleanup
    • Lead
    • Mold
    • Radon
    • Research
    • Science Topics
    • Water Topics
    • A-Z Topic Index
    • Laws & Regulations
    • By Business Sector
    • By Topic
    • Compliance
    • Enforcement
    • Laws and Executive Orders
    • Regulations
    • Report a Violation
    • Environmental Violations
    • Fraud, Waste or Abuse
    • About EPA
    • Our Mission and What We Do
    • Headquarters Offices
    • Regional Offices
    • Labs and Research Centers
    • Planning, Budget, and Results
    • Organization Chart
    • EPA History

Chesapeake Bay Total Maximum Daily Load (TMDL)

  • Key Developments

    See Key Developments

    EPA Issues Updated Assessment on Virginia's Animal Agriculture Programs

    EPA evaluates Two-year Milestone progress and commitments

    EPA Activities Pursuant to 2023 Settlement Agreement

  • Ensuring Results

    A number of elements are in place to ensure implementation of the Chesapeake Bay TMDL.

  • Learn about the Chesapeake

    Watch educational videosExit
    put together by our partners
    at the Chesapeake Bay Program

    • Monitoring and Modeling the Chesapeake BayExit
  • Have a Question?

    View our Frequent Questions or Contact Us.

EPA Evaluates Two-year Milestone Progress and Commitments
EPA released its evaluations of the 2022-2023 progress and final 2024-2025 milestone commitments.

Read EPA’s evaluations of Two-year Milestones Progress and Commitments

Read the Press Release 

What is the Bay TMDL?

What is the Bay TMDL?

On December 29, 2010, the U.S. Environmental Protection Agency established the Chesapeake Bay Total Maximum Daily Load (TMDL). The TMDL is a historic and comprehensive "pollution diet" to restore clean water in the Chesapeake Bay and the region's streams, creeks, and rivers.

  • Bay TMDL Document
  • Bay TMDL Fact Sheet
  • Bay TMDL Development
  • Frequent Questions
Brook Trout in Pendleton County WV

Implementing the TMDL

A number of elements are in place to ensure that all pollution control measures needed to fully restore the Bay and its tidal rivers are in place by 2025. Practices will also be in place by 2017 to meet 60 percent of the necessary pollution reductions.

  • Watershed Implementation Plans (WIPs)
  • Milestones
  • Air Pollution Reductions
  • Wastewater Pollution Reductions
  • Trading and Offsets
  • Midpoint Assessment
Basket of Chesapeake Bay Oysters

Progress in the Watershed

Actions are being taken across six states and the District of Columbia to reduce nitrogen, phosphorus and sediment loads to meet the clean water goals of the Bay TMDL.Actions are being taken across six states and the District of Columbia to reduce nitrogen, phosphorus and sediment loads to meet the clean water goals of the Bay TMDL. EPA is also implementing the 2023 Settlement Agreement.

  • EPA Oversight
    • WIPs and Milestones
    • Sector-Specific
    • EPA Activities Pursuant to 2023 Settlement Agreement
  • Key Developments
  • Tracking Tools
  • Watershed Happenings

Watershed Map

Map of the Chesapeake Bay Watershed.
The Chesapeake Bay Watershed spans six states and the District of Columbia. 

Connect with the Bay

  • Read the Bay Journal
  • Watch educational videos about the Bay on the Chesapeake Bay Program website
  • Follow the Bay Program on X
  • Like the Bay Program on Facebook

Additional Resources

  • Funding Opportunities
  • Correspondence and Guides
  • Technical Support Documents
  • Federal Register Notices
  • Executive Order 13508
  • Bay Watershed Agreement
  • Contact Us
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on March 10, 2025
  • Assistance
  • Spanish
  • Arabic
  • Chinese (simplified)
  • Chinese (traditional)
  • French
  • Haitian Creole
  • Korean
  • Portuguese
  • Russian
  • Tagalog
  • Vietnamese
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
  • Inspector General
  • Jobs
  • Newsroom
  • Regulations.gov
  • Subscribe
  • USA.gov
  • White House

Ask.

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

Follow.