ANNAPOLIS, Md., June 3, 2025 — The Chesapeake Bay Program reported significant progress in reducing nitrogen, phosphorus, and sediment pollution entering the Chesapeake Bay between 2009 and 2024. The seven jurisdictions in the Bay watershed—Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia, and the District of Columbia—have advanced efforts to meet the 2025 goals set by the Chesapeake Bay Total Maximum Daily Load (Bay TMDL). The Bay TMDL requires all practices to be in place by 2025 to achieve water quality standards.
From 2009 to 2024, nitrogen pollution decreased by 15.3%, from 297.1 million pounds to 251.6 million pounds, achieving 59% of the 2025 target. Phosphorus pollution dropped 21.8%, from 16.8 million pounds to 13.1 million pounds, meeting 92% of the goal. Sediment pollution fell 7.6%, from 18.83 billion pounds to 17.39 billion pounds, fully meeting the 2025 target. These estimates, generated by the Chesapeake Bay Program’s Watershed Model, incorporate data on land use, fertilizer, wastewater, and best management practices (BMPs).
The agricultural sector drove 76% of nitrogen reductions between 2023 and 2024, while the natural sector—encompassing trees, shorelines, forests, and wetlands—accounted for 46% of phosphorus and 77% of sediment reductions. Improved data and increased BMP reporting, particularly for phosphorus, contributed to these gains. The 2024 model update, reflecting higher fertilizer use, adjusted baseline pollution calculations set in 2010.
The Chesapeake Bay Program introduced two new indicators in 2024: the Bay TMDL Indicator and the Monitored and Expected Total Reduction Indicator for the Chesapeake (METRIC). These tools combine modeling and water quality monitoring data to better track progress and inform decision-making. Updates to these indicators are expected by July 2025. Progress toward the 2025 goals is detailed on the 2025 Watershed Implementation Plan Outcome webpage on ChesapeakeProgress, with final assessments due in 2026.
Excess nitrogen, phosphorus, and sediment impair the Bay’s water quality, fueling algae blooms, creating low-oxygen “dead zones,” and blocking sunlight needed by underwater grasses. BMPs, such as those used in agriculture and urban stormwater management, help reduce these pollutants. While point-source reductions, like wastewater treatment upgrades, show immediate results, non-point sources, such as agricultural runoff, often require time to impact water quality.
“These results highlight the meaningful progress that Maryland has made with our partners to improve the waterways that sustain the Chesapeake. Through collaboration, dedication and proven strategies, we’ve achieved reductions across all sources and are nearing our targets. We’re committed to building on this momentum for lasting improvements and a healthier Bay,” said Gregorio Sandi, Vice-Chair, Chesapeake Bay Program Water Quality Goal Implementation Team and Chief, Watershed Restoration Planning Division, Maryland Department of the Environment.
In Virginia, conservation efforts are gaining traction. “Virginia’s soil and water conservation districts (SWCD) and the producers they work with are dedicated to continually improving practices that enrich our natural resources. Districts across the Commonwealth provide a one-stop shop for farmers to take advantage of technical assistance and tailored funding options offered by District staffers, and to sign-up for state cost-share programs that fund conservation practices. We are proud of the relationships and the trust built with these farms, many dating back decades, and are appreciative for the opportunity to assist the agricultural community while expanding these mutually beneficial partnerships that enhance our lands and waters. With a historic funding opportunity beginning on July 1, 2025, that fully funds the agriculture needs assessment and necessary technical assistance, there is momentum across SWCDs to continue to ramp up their efforts. Our outreach and adoption efforts are evident not only in improved water quality and decreased pollutant loads, but also in stronger community connections,” said Kendall Elaine Tyree, PhD, Executive Director, Virginia Soil and Water Conservation Districts.
Community engagement is also key. “It’s my opinion that one of the greatest successes of the Chesapeake Bay Program is its ability to connect with audiences throughout the entire watershed and help them realize the impacts their actions have upon one another. These connections are wide reaching—from educating those downstream on the importance of stormwater catchments, tree canopy cover and working forests, to helping those in the headwaters realize the impacts of their actions on folks living next to the Bay,” said Jeremy McGill, Assistant State Forester, West Virginia Department of Forestry.
The Chesapeake Bay Program is revising the Chesapeake Bay Watershed Agreement to update its 2025 goals. Details on this process are available on the Planning for 2025 and Beyond website. The Environmental Protection Agency uses these pollution estimates to ensure jurisdictions meet Bay TMDL targets and two-year milestones, supporting efforts to restore habitats, improve water quality, and sustain the Bay’s ecosystem.
