Excess nitrogen, phosphorus and sediment from waste water treatment plants, agricultural operations, urban and suburban runoff, wastewater facilities, 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. Though the nutrient contamination levels of the Chesapeake Bay have decreased over the past thirty years, the Bay’s waters remain degraded. 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 is a 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 intend to achieve their assigned pollution reduction goals. These plans are called the Watershed Implementation Plans, WIPs, and lay out a series of pollution control measures that need to be put in place by 2025, with 60% of the steps completed by 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 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.
The EPA reviews our progress every two years against milestones. The two-year milestones are short-term objectives under the Chesapeake Bay TMDL used to assess progress towards our mandated restoration goals to allow the state some flexibly to adapt the Watershed Implementation Plans to meet the goals. Overall Virginia was found to have achieved its state-wide 2015 milestone targets for nitrogen and phosphorus, but did not meet its state-wide target for sediment as a result of being off track for sediment in the Agriculture and Urban/Suburban Stormwater sectors. Reductions in the Wastewater sector remain ahead of schedule for all three pollutants.
The EPA review of progress toward meeting 2014-2015 milestones shows Virginia achieved most of its numeric milestones. Virginia met its state-wide targets, in part, because of greater than expected wastewater reductions achieved by having completed wastewater treatment plant improvements and expansions ahead of population growth.
Based on Virginia’s anticipated reductions for nitrogen, phosphorus and sediment planned for the 2016-2017 milestone period, Virginia is expected to catch up and be on track to meet all its state-wide targets for 2017. To catch up Virginia needs to increase implementation of pollution reduction measures in the Agriculture, Urban/Suburban Stormwater and Septic sectors. The sources of pollution in these areas are non-point source pollution (NPS), diffuse sources of pollution. These pollutants do not come out of a pipe, but are carried to streams and rivers by runoff of rain and snowmelt. The way to reduce impact of this non-point source pollution on the environment is to implement what has been called “best management practices.” There are BMPs to minimize the use of fertilizers and pesticides; and BMPs to reduce runoff and slow rain water while maintaining or even enhancing agricultural production. Now Virginia is expanding these BMPs to suburban neighborhoods. Virginia’s anticipated reductions for the 2016-2017 milestone period should keep it on track to meet the 2017 target of having practices in place to achieve 60% of the reductions necessary for nitrogen, phosphorus and sediment pollution.
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| image from Chesapeake Bay Program |
EPA will maintain “Enhanced Oversight” of Virginia for the Urban/Suburban Stormwater and will continue to monitor Virginia’s progress in closing the nutrients and sediment gap in the 2016-2017 milestone period. EPA will maintain “Ongoing Oversight” of the Virginia sectors for Agriculture, Wastewater and Offsets and Trading which are doing much better at tracking the milestones agreed to with the EPA.
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