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Chesapeake Bay TMDL

Chesapeake Bay TMDL Midpoint Assessment

The Chesapeake Bay TMDL document called for an assessment in 2017 to review progress toward meeting the nutrient and sediment pollutant load reductions necessary for Bay restoration. This midpoint assessment was finalized in 2018 and measured the Bay jurisdictions' progress towards meeting the 2017 goal of having practices in place to achieve 60 percent of the necessary reductions compared to 2009 levels. The Bay jurisdictions include Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia and the District of Columbia.

The ultimate goal is to have all practices and controls in place by 2025 to achieve the Bay's dissolved oxygen, water clarity/submerged aquatic vegetation and chlorophyll-a standards.

As part of this midpoint assessment, the Chesapeake Bay Program (CBP) partnership reviewed the latest science, data, modeling and decision support tools used to measure progress. The intent of this part of the midpoint assessment is to strengthen the CBP partnership's decision support capabilities to optimize the jurisdictions' Phase III Watershed Implementation Plans (WIPs).

The Phase III WIPs, finalized in August 2019, provide information on what actions the jurisdictions intend to implement between 2018 and 2025 to meet the Bay TMDL restoration goals.

For more information on the Midpoint Assessment, please click on the links below:

EPA Final Evaluation of 2016-2017 Milestone and Midpoint Progress and 2018-2019 Milestone Commitments

Fact Sheet on the Midpoint Assessment of the Chesapeake Bay Total Maximum Daily Load  (PDF) (4 pp, 4 K, About PDF

Chesapeake Bay Program Bay TMDL 2017 Midpoint Assessment (scroll down to Chesapeake Bay TMDL 2017 Midpoint Assessment)Exit

Scenario Builder and Watershed Model Plan for the Midpoint Assessment (scroll down to see Phase 6 Model and Midpoint Assessment and Phase 6 Scenario Builder Review)Exit

Water Quality Goal Implementation TeamExit

Final Phase III WIPs (click on the "Phase III WIPs" tab)

EPA's Evaluations of Draft Phase III WIPs