Chesapeake Bay TMDL

EPA Oversight of Watershed Implementation Plans (WIPs) and Milestones in the Chesapeake Bay Watershed

The TMDL is being implemented using an accountability framework that guides restoration efforts using four elements. These elements include Watershed Implementation Plans (WIPs), two-year milestones, EPA’s tracking and assessment of restoration progress and, as necessary, specific federal actions if the Bay jurisdictions do not meet their commitments. Bay jurisdictions include Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia and the District of Columbia.

Under the accountability framework, EPA committed to conduct ongoing oversight of Bay jurisdictions' programs to ensure they are on track to meet the goals of their WIPs and two-year milestones.

EPA Evaluations

EPA evaluates the milestone commitments that each jurisdiction makes every two years. In addition, EPA conducts, at a minimum, biennial reviews of the progress that each jurisdiction has made towards achieving the TMDL targets and milestone commitments.  EPA identifies its level of oversight for each sector in each jurisdiction.  The current status is shown here:

Graphic showing the level of EPA oversight for each sector in each jurisdiction of the Chesapeake Bay watershed

Ongoing oversight: EPA, while having no significant concerns with a jurisdiction’s strategy to implement the TMDL goals, will continue to monitor progress. 

Enhanced Oversight: EPA, having identified specific concerns with a jurisdiction’s strategy to implement the TMDL goals, may take additional federal actions, as necessary, to ensure that the jurisdiction stays on-track. 

Backstop Actions Level: EPA, having identified substantial concerns with a jurisdiction’s strategy to implement the TMDL goals, has taken necessary Federal Actions to help the jurisdiction get back on-track. 

EPA Final Evaluation of 2014-2015 Milestone Progress and 2016-2017 Milestone Commitments

EPA Interim Evaluation of 2014-2015 Milestone Progress

EPA Final Evaluation of 2012-2013 Milestone Progress and 2014-2015 Milestone Commitments

EPA Interim Evaluation of 2012-2013 Milestone Progress

EPA Evaluation of Final 2012-2013 Milestones Commitments and Phase II WIPs

EPA Evaluation of Phase I WIPs

2009-11 Milestones to Reduce Nitrogen and Phosphorus - Assessment June 2012(PDF)Exit(14 pp, 1.5 M, About PDF)

Federal Actions

EPA's goal is for the Bay jurisdictions to successfully implement their Watershed Implementation Plans (WIPs) and two-year milestones to achieve the necessary nutrient and sediment reductions. However, EPA is prepared to take federal actions if it is necessary and appropriate to do so to help the jurisdictions reach their targets. Federal actions can be taken at any time. Potential actions could include:

  • Expand National Pollutant Discharge Elimination System (NPDES) permit coverage to unregulated sources.
  • Expand EPA oversight review of state-issued NPDES permits and EPA objection to inadequate permits.
  • Require net improvement offsets for new or increasing loadings.
  • Establish finer-scale waste load allocations and load allocations in the Chesapeake Bay TMDL.
  • Require additional reductions of loadings from point sources.
  • Increase and target federal enforcement and compliance assurance, including both air and water sources of nitrogen, phosphorus and sediment.
  • Condition or redirect EPA grants.
  • Federally promulgate local nutrient water quality standards (WQS).

For more information on the potential actions, please visit:

Program Contacts

If you have additional questions regarding EPA's evaluations of the Watershed Implementation Plans (WIPs) and two-year milestones, please contact the appropriate EPA staff member listed on our Program Contacts page.