The Chesapeake Bay, North America’s largest estuary, is a national treasure with nearly 12,000 miles of shoreline and economic and recreational benefits estimated at $33 billion a year (PDF).1 Among the Bay’s resources are more than 2,700 plant species, nearly 350 species of finfish and 175 species of shellfish, including the iconic blue crab. Every year more than a million birds winter in the Bay region, and the Bay's waters produce more than 500 million pounds of seafood.
But the Bay is in trouble and has been for some time. During the 1970s, the many stresses on the Bay became apparent: important underwater grasses disappearing; areas of low or no oxygen developing; and harvests of oysters, crabs and striped bass dropping dramatically.2
In 1983, three governors joined with the Administrator of the Environmental Protection Agency (EPA) and the Mayor of the District of Columbia, pledging cooperation to improve water quality (PDF) and protect the Bay’s resources.3 This early effort acknowledged the complexity of the restoration task and identified priorities for action. Chief among those was the reduction of the nitrogen and phosphorus that had fueled the overenrichment of Bay waters and set in motion a spiral of harmful impacts.
Since that time, cleanup has continued, engaging policymakers in Maryland, Delaware, Pennsylvania, Virginia, the District of Columbia, New York, West Virginia and numerous federal agencies. Scientific expertise has been marshaled and sophisticated models employed to predict the impact of various actions on Bay health. Billions in state and federal funds have been spent on water quality protection, improved agricultural practices, land use planning and habitat restoration. Despite these efforts, however, it is now widely understood that the Bay’s legacy will remain in jeopardy unless and until additional dramatic reductions in nitrogen, phosphorus and sediment can be made.
New Cleanup Commitments
Today, the Bay states and the EPA are involved in an unprecedented large-scale effort to achieve those reductions. This effort involves using the federal Clean Water Act to establish a Total Maximum Daily Load (TMDL) or “pollution diet” for the Chesapeake and each of its tributaries.
The Bay’s TMDL covers the entire 64,000 square miles of the watershed and sets an overall limit on the amount of nitrogen, phosphorus, and sediment that can flow into it. The total quantity of these pollutants that scientists believe the Bay can tolerate is well below current levels, and each Bay state has been assigned a pollution allocation, or share of that total. To ensure that these allocations are not exceeded, each jurisdiction is preparing a watershed implementation plan (WIP) to describe how the shares will be divided among pollution sources, and what steps will be taken to achieve the necessary reductions. The states may phase in their selected controls, but all of the measures must be fully in place by 2025.
In 2010, the Phase I WIPs were completed and approved by the EPA. The Phase II WIPs (PDF) are due for final approval March 30, 2012, and must identify how the jurisdictions will ensure that 60 percent of their controls are in place by 2017. The Phase III WIPs are due in 2017. In the meantime, progress will be monitored with reporting on a series of two-year milestones selected by each state.
Fair Shares for Reducing Pollution
In the Bay watershed, as elsewhere, nitrogen, phosphorus and sediment come from a diverse range of sources. The culprit pollutants can flow from wastewater treatment plants and industrial facilities, run off of urban streets, suburban lawns, construction sites and farm fields, seep slowly into streams from polluted groundwater and fall to the ground from polluted air.
Current estimates indicate that agriculture is the largest source of these pollutants overall, contributing nearly half of the Bay’s phosphorus and nitrogen and more than half the sediment.5 These pollutants result from runoff from fields fertilized with commercial fertilizers and manure as well as airborne releases of ammonia, a form of nitrogen that escapes from manure storage lagoons, poultry houses and manured cropland.
Farming and farmland has long been an important part of the Bay region and, the preservation of those traditions can contribute significantly to the improved health of the Bay. Achieving Bay nutrient reductions as outlined in the TMDL, however, will require significant improvements in the farming practices that are regulated by the states, particularly those associated with manure from intensive animal confinement.
1 EPA Needs to Better Report Chesapeake Bay Challenges: A Summary Report, Evaluation Report (US EPA, Office of
Inspector General, July 14, 2008), http://www.epa.gov/oig/reports/2008/20080714-08-P-0199.pdf.
2 Robin Herbst, The State of the Chesapeake Bay: A Report to the Citizens of the Bay Region (Annapolis, Maryland: US
EPA, Chesapeake Bay Program, July 2002).
3 1983 Chesapeake Bay Agreement, http://www.chesapeakebay.net/content/publications/cbp_12512.pdf.
4 More information can be found at the US Environmental Protection Agency’s Chesapeake Bay TMDL website.
http://www.epa.gov/chesapeakebaytmdl/
5 US Environmental Protection Agency, “Draft Total Maximum Daily Load (TMDL) for the Chesapeake Bay,” Section 4,
September 22, 2010 (Federal Register, Volume 75, Number 183).
