States and local jurisdictions in the Chesapeake Bay watershed are working toward water quality goals for the Bay and its rivers. The U.S. Environmental Protection Agency spells out those goals, with a deadline set for 2025, in the Bay’s “pollution diet” — formally known as the total maximum daily load. Each state has a role to play, and each state is coordinating related projects in its counties, towns, and cities.

What’s expected of your local community?

To find out, you could read your state’s 2019 Watershed Implementation Plan. But a better approach may be to review its Two-Year Milestones.

What are Two-Year Milestones?

Each state in the Bay watershed, as well as the District of Columbia, sets Two-Year Milestones to show what it will accomplish during a 24-month timeframe to advance the state’s WIP and ensure progress toward the 2025 pollution reduction goals.

Two-year milestones have been part of state and local cleanup plans for the Bay since the EPA established the TMDL in 2010. The states agreed to set these short-term goals as part of the TMDL accountability framework.

There are two types of milestones: programmatic and numeric.

Volunteers participate in a 2014 tree planting event along a stream in Frederick County, MD. In many places, increasing streamside buffers can be credited toward reaching a state’s Two-Year Milestones in the Chesapeake Bay cleanup effort. Credit: Will Parson / Chesapeake Bay Program

What are programmatic milestones?

Programmatic milestones are the actions a state will take to achieve, enable, or require nutrient and sediment reduction. Examples include updating erosion and sedimentation permit requirements, reissuing MS4 permits, hiring staff to inspect farms for compliance with regulations, and launching new funding programs.

What are numeric milestones?

Numeric milestones predict how many units of each pollution reduction practice will be implemented during the coming two years. For example, states may estimate how many acres of cover crops will be planted, how many trees will be planted, how many acres of wetlands will be restored, and so on until they reach the required pollution limits for nutrients and sediment.

States have two options for developing numeric milestones. The first is to create an “input deck,” forecasting the number of best management practices required for achieving their nutrient and sediment limits. They do this using the Chesapeake Assessment Scenario Tool, a web-based tool found at

The second is to work with the EPA to establish the targets. This alternative allows states to develop milestones for a smaller subset of practices as opposed to the entire suite of practices included in their WIP. It also provides flexibility to project implementation resulting from programmatic actions such as dollars committed or staff hired.

This parking lot structure in St. Michaels, MD, is designed to reduced stormwater runoff. Credit: Will Parson / Chesapeake Bay Program

Who sets the milestones?

Milestones are set by state environmental agencies in consultation with other state agencies such as departments of agriculture. Ideally, states engage those working at the local level to ensure that the needed resources are available and that the forecasts for implementation are realistic and align with local goals and priorities.

What is the milestone schedule?

Draft milestone commitments are submitted to the EPA at the beginning of even-numbered years (2020, 2022, 2024). States generally begin drafting their milestones during the last quarter of odd-numbered years (2021, 2023). This is when states should engage local jurisdictions and other partners in the process.

The draft milestones must be posted on state websites, then go through a period of review before being finalized. This can take several months. The current milestone period began on Jan. 1, 2020, and extends through Dec. 31, 2021.

States report their progress toward meeting milestone commitments to the EPA at the end of each calendar year. At the end of the two-year milestone period, a formal evaluation is conducted and published by the EPA.

What responsibilities do local jurisdictions have for meeting the milestones?

Some milestone commitments come from permits issued to local jurisdictions, such as MS4 or wastewater permits. These permits, issued by the state, project the pounds of nutrients or sediment that will be reduced through permit compliance. Local jurisdictions should be prepared to meet these regulatory obligations and report on their progress.

Other commitments made by the state are voluntary for local jurisdictions or organizations unless the local jurisdiction has entered into some form of a contractual agreement or formal commitment. For example, a state may commit to planting trees, then develop a funding program to incentivize a local jurisdiction to participate in achieving the goal. This type of commitment would only become a requirement when or if there is a contract, such as a grant award, between the state and the local jurisdiction or organization.

Whether commitments are required or voluntary, local jurisdictions can help ensure milestones are met by accurately tracking, verifying, and reporting the activities implemented in their community. The states rely heavily on the local reporting of practices implemented. This may be done in the form of MS4 annual reports, grant progress reports, reporting by soil and water conservation districts, or a variety of other means. For example, Virginia developed a web-based BMP Warehouse for the local reporting of BMPs implemented.

Where can I find my state’s milestones?

Milestones are posted on the state websites and the EPA’s Chesapeake Bay TMDL website.

How is milestone success evaluated?

At the end of each Two-Year Milestone period, states review their accomplishments against the commitments that were made and report their progress to the EPA. The EPA evaluates each state’s reported progress and provides feedback. The EPA’s evaluation acknowledges achievements, and it highlights missed goals and areas to be addressed during the next two years. You might think of the evaluation as a report card, intended to help the states achieve their overall goal.

At the end of each calendar year, states must also submit a report of BMPs implemented during the previous July 1 through June 30 reporting period. Beginning in 2019, only practices that have been verified to be in place and functioning as intended are able to be counted.

How can I learn more?

Projects that reduce stormwater runoff don’t just help the Chesapeake Bay. They help reduce local flooding and water pollution, too. Credit: Dave Harp

To learn about the process your state uses in developing its milestones or to provide feedback, reach out to your state contact person, listed at

For detailed information about the Chesapeake Bay TMDL, including links to state WIPs and milestones, EPA evaluations, and more, visit

Explore the Chesapeake Assessment Scenario Tool at

More Information

Learn more about Two-Year Milestones in your state on these websites:

Terms to know

Milestones: Short-term (2-year) goals established by each state and the District of Columbia to evaluate progress toward achieving the pollution limits established in the Chesapeake Bay TMDL.

BMP: Acronym for best management practice, generally referring to a method or technique for managing pollutant discharge. Examples include cover crops, bioswales and wetland enhancement.

Input deck or scenario: The state’s projection of how many BMPs will be implemented over a period of time. The number is entered into a computer model to determine whether the desired pollution reduction goals will be met.

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