Excess nitrogen, phosphorus and sediment from waste water treatment plants, agriculture, urban and suburban runoff, septic systems, air pollution and other sources have impaired the Chesapeake Bay and its tidal waters. These pollutants cause algae blooms that consume oxygen and create dead zones where fish and shellfish cannot survive, block sunlight that is needed for underwater grasses, and smother aquatic life on the bottom.
Since the 1980’s the six bay states- Virginia, Maryland, West Virginia, Delaware, Pennsylvania, New York-and Washington DC have been trying to clean up the Chesapeake Bay with some, but not enough progress as inconsistent levels of effort were put into the task across all the jurisdictions. As a result, U.S. Environmental Protection Agency, EPA, mandated a contamination limit called the TMDL (total maximum daily load for nutrient contamination and sediment) to restore the local waters.
The TMDL sets a total Chesapeake Bay watershed limit for the six states and Washington DC of 185.9 million pounds of nitrogen, 12.5 million pounds of phosphorus and 6.45 billion pounds of sediment per year which was about 25% reduction in nitrogen, 24% reduction in phosphorus and 20 % reduction in sediment from the 2011 levels. The pollution limits were then partitioned to the various states and river basins based on the Chesapeake Bay computer modeling tools and monitoring data.
The six states and Washington DC were required to submit and have approved by the EPA a detailed plan of how they intended to achieve their assigned pollution reduction goals. These plans, Watershed Implementation Plans (WIPs), laid out a series of pollution control measures that need to be put in place by 2025, with 60% of the steps to have been completed by the mid-point assessment in 2017.
While it will take years after 2025 for the Bay and its tributaries to fully heal, EPA expects that once the required pollution control measures are in place there will be gradual and continued improvement in water quality as the nutrient and sediment run off is reduced and there is better control storm water so that the Chesapeake Bay ecosystem can heal itself.
About half of the 39,490 square mile land area of Virginia is drained by the creeks, streams and rivers that comprise the Chesapeake Bay watershed, and two-thirds of the state's population lives within the watershed. To develop a remediation plan acceptable to the EPA and likely to achieve the goals of the revised WIP, the state legislature passed a series of laws and the state implemented a series of regulations addressing among other items: nutrient management plans, septic regulations, limitations of the sale and use of lawn maintenance fertilizer, banning deicing agents containing urea, nitrogen, or phosphorus intended for application on parking lots roadways, and sidewalks, or other paved surfaces, etc.
At the mid-point assessment the EPA’s Chesapeake Bay Program found that overall “Virginia has made progress in wastewater and agriculture, but needs to improve stormwater cost-share programs, account for growth in poultry farming, and strengthen MS4 requirements.” Right now Virginia has begun work on the third and final iteration of their clean-up plans, known as the Phase III Watershed Implementation Plans (WIPs). These plans will describe actions to take, between now and 2025—the deadline for full implementation.
Virginia has made substantial progress towards addressing pollution to satisfy the Chesapeake Bay TMDL goals, especially in wastewater but also in agriculture. There has also been progress reducing polluted runoff from urban and suburban areas, although any progress has been overshadowed by increased land conversion from agricultural uses and permit delays. Looking forward, Virginia must make a substantial shift toward reducing pollution from stormwater, agriculture, and septic systems. The One of the most important steps to addressing these issues is establishing strong incentives for local governments and ensuring they have all the tools and resources necessary to succeed.
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