The first multi-state agreement to clean up the Chesapeake Bay dates back to 1983. But by 2008, after three more agreements, the region was still decades away from the goal of restoring the Chesapeake Bay. Recognizing that the Chesapeake Bay was a national gem that needed federal support, President Obama signed an executive order in 2009 directing agencies like the Environmental Protection Agency (EPA) to help the Bay states restore clean water. That same year, the Chesapeake Executive Council set short-term restoration goals—called two-year milestones—to hasten restoration and increase accountability.
Chesapeake Bay TMDL and Watershed Implementation Plans
In 2010, the EPA established the landmark Chesapeake Bay Total Maximum Daily Load (TMDL). The Chesapeake Bay TMDL set limits on the amount of nutrients (phosphorous and nitrogen) and sediment that can enter the Bay and its tidal rivers to meet water quality goals. These limits are often referred to as a “pollution diet” or a “pollution budget.”
To restore the Bay, we need to reduce 25% of the nitrogen loads, 24% of the phosphorus and 20% of the sediment. While the Bay TMDL sets the target, it’s still up to the states to decide how to get there. Each state writes a series of Watershed Implementation Plans, with the tools and best management practices that will reduce its pollution load to meet the Bay TMDL pollution reductions by 2025. Federal, state and local governments coordinate through the Chesapeake Bay Program partnership to develop the WIPs. The third WIPs were issued the spring of 2019.
Still Much Work to be Done to Meet Targets
The dead zone in the Chesapeake Bay is most pronounced in the deep waters of the Bay’s main stem during warm summer months. The average size of the dead zone is approximately 1.89 cubic miles, or nearly the volume of 3.2 million Olympic-size swimming pools. Between 1985 and 2010, the duration of the dead zone fell from five months to four, suggesting efforts to manage nutrient pollution through upgrades to wastewater treatment plants, cuts to vehicle and power plant emissions, and reductions in runoff from farmland are working. While rainfall and weather patterns affect the development of the dead zone, nutrient pollution is the foremost factor in its growth. In addition to dead zones, excess nutrients in the water and the resulting algae blooms can result in the production of algal toxins and strange tastes and smells in drinking water. One of our priorities to the relicensing of the Conowingo Dam, a hydroelectric dam that has been trapping sediment from the Susquehanna River, blocking fish passage, and affecting the water quality of the Chesapeake Bay since it was built in 1928. Nearly 200 million tons of sediment pollution have accumulated behind the dam. During major floods caused by large storms, powerful floodwaters can scoop out or “scour” the stored sediment behind the dam and send that downstream to the Chesapeake Bay.
Throughout this process, our focus has been on the cleanup and restoration of our local waterways, including taking actions to guarantee effective TMDLs for local waterways and to guarantee Watershed Implementation Plans that are accountable, funded and meet restoration goals.
The Restoration of the Bay Starts with Local Streams & Communities
Take Action to Strengthen the Cleanup Plan for Conowingo Dam
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