New modeling from the Chesapeake Bay Program shows significant declines in pollutants entering the Bay between 2009 and 2025 — though the watershed’s states remain well short of their nitrogen reduction target even as they’ve fully met their sediment goal.
As of 2025, jurisdictions across the Bay watershed have met 100% of their sediment reduction goal, 90% of their phosphorus goal, and 57% of their nitrogen goal, according to the Chesapeake Bay Program’s latest estimates, released Aug. 6. Sediment entering the Bay fell 6.8% since 2009, phosphorus fell 21.4%, and nitrogen fell 15% — measured against a 2009 baseline set under the Chesapeake Bay Total Maximum Daily Load. Wastewater treatment plant upgrades have driven the majority of nitrogen and phosphorus reductions since 2009 (64% and 61%, respectively), while agriculture accounted for 43% of sediment reductions. More recently, nonpoint sources like agriculture and stormwater runoff have driven a growing share of nitrogen and phosphorus gains between 2020 and 2025.
Excess nitrogen and phosphorus fuel algal blooms that cloud Bay waters and consume oxygen as they die and decompose, while excess sediment smothers oyster reefs and blocks sunlight underwater habitats need.
Federal and state officials largely framed the results as validation of the region’s collaborative approach. EPA Mid-Atlantic Regional Administrator Amy Van Blarcom-Lackey called it “cooperative federalism in action.” Pennsylvania Gov. Josh Shapiro said the state has cut farm-to-Bay pollution three times faster over the past five years than the previous decade, restored streams cumulatively stretching “from Harrisburg to Annapolis,” and helped more than 2,000 farmers adopt conservation practices. Maryland DNR Secretary Josh Kurtz said Maryland individually achieved 100% of its sediment and phosphorus goals and 99% of its nitrogen goal — outpacing the watershed-wide averages. Virginia’s Secretary of Natural and Historic Resources, David Bulova, pointed to a $304 million investment in the state’s agricultural conservation cost-share program, and West Virginia DEP Secretary Harold Ward said his state has met all of its Bay pollutant reduction goals.
Chesapeake Bay Foundation President and CEO Hilary Harp Falk struck a more cautious note. “There is real progress in these numbers, and it is worth celebrating,” Falk said in a statement. “But modeled pollution reductions are only part of the story. What ultimately matters is what we see and measure in our rivers, streams, and the Chesapeake Bay itself—which indicates there is still significant work to be done.”
Falk called for more monitoring “to understand how the system is responding,” and argued that officials need “the courage to change course when the evidence tells us something isn’t working as expected.” She pointed to specific ongoing problems: pollution still fouling Baltimore Harbor, “troubling signs” in rivers like the Choptank, worsening flooding in Norfolk tied to climate change, algal blooms in Virginia waters, and tens of thousands of miles of impaired rivers and streams in Pennsylvania. That last figure checks out — Pennsylvania’s own draft 2026 water quality report found 31,451 miles, or about 37% of the state’s rivers and streams, fail to meet water quality standards.
The reductions are part of the framework set by the revised Chesapeake Bay Watershed Agreement, adopted last year, which set 2025 as the initial target date for these pollutant reductions. Under the revised agreement, jurisdictions will keep working toward the targets through 2030, at which point the targets themselves will be updated based on the latest science, with jurisdictions then developing plans to meet the revised targets by a final 2040 deadline. CBF separately argues states should have investments and policies in place to meet the 2040 goals well before the deadline arrives, rather than waiting.
