Chesapeake Bay Watershed Pollution Limits


Jon McRay

If fully implemented, the Chesapeake Clean Water Blueprint—the federal/state effort enacted in late 2010—will ensure programs to reduce nitrogen, phosphorus, and sediment pollution sufficiently to get the Bay and its tributaries off the Clean Water Act "Impaired Waters" list are in place by 2025.

The Environmental Protection Agency (EPA) established the following science-based limits (also called the Total Maximum Daily Load or TMDL) for nitrogen, phosphorus, and sediment necessary for the Chesapeake Bay watershed to restore the Bay and its tidal rivers to health.

What It Will Take to Restore the Bay and Its Tidal Rivers to Health

Reduce Bay-wide nitrogen loads to:Reduce Bay-wide phosphorus loads to:Reduce Bay-wide sediment loads to:
219.53 million lbs/year by 2017 16.35 million lbs/year by 2017 7.87 billion lbs/year by 2017
199.27 million lbs/year by 2025 13.31 million lbs/year by 2025 18.58 billion lbs/year by 2025

~ Source: Chesapeake Bay Program, Watershed Model 5.3.2

Pollution Reduction Progress Toward 2025 Goals

Nitrogen Loads
to the Bay
(million lbs/year)
Phosphorus Loads
to the Bay
(million lbs/year)
Sediment Loads
to the Bay
(billion lbs/year)
1985 369.78 25.62


2009 282.66 19.23 8.68
2012 264.14 17.97 8.24
2016 240.24 15.37 7.92
2017 233.10 14.95 7.79
2021 240.45 14.71 18.06
2025* 199.27 13.31 18.58
  Source: Chesapeake Bay Program Source: Chesapeake Bay Program Source: Chesapeake Bay Program

~ Source: Chesapeake Bay Program, Watershed Model 5.3.2

NEXT: The Bay states' role in the Chesapeake Clean Water Blueprint 

Pollution Limits by State

The Bay Needs You

The State of the Bay Report makes it clear that the Bay needs our support now more than ever. Your donation helps the Chesapeake Bay Foundation maintain our momentum toward a restored Bay, rivers, and streams for today and generations to come.

Donate Today


Do you enjoy working with others to help clean the Chesapeake Bay? Do you have a few hours to spare? Whether growing oysters, planting trees, or advocating for a clean Bay, there are plenty of ways you can contribute.

This website uses cookies to tailor and enhance your online experience. By continuing, you are agreeing to our use of cookies. For more information, including details on how to disable cookies, please visit our Privacy Policy. Close