Last week Russ Baxter the Deputy Secretary of Natural Resources in Virginia briefed a handful of elected officials in Northern Virginia on the status of the Chesapeake Bay TMDL Phase III Watershed Implementation Plan (WIP). It was a small turnout, but it was the first in what is planned to be a series of meetings during the development of the WIP III. About a third of the entire area of the Chesapeake Bay Watershed is within Virginia; 55% of Virginia’s land area drains to the Chesapeake Bay and the WIP directly impacts 75% of Virginia’s population that lives in the Chesapeake Bay Watershed. Within Virginia’s Chesapeake Bay Watershed area, forest covers 66% of the land, agriculture covers 20%, urban/suburban covers 13% and isolated ponds and water covers the rest. The WIP III will have a large impact on the cities, towns, farms and land use regulations within the Chesapeake Bay Watershed. Make sure your elected officials are engaged in the process.
Though the nutrient contamination levels of the Chesapeake Bay have decreased over the past thirty years, the Bay’s waters remain degraded. In 2010 the 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 tributary local waters to Virginia, Maryland, West Virginia, Delaware, Pennsylvania, New York-and Washington DC. This TMDL is what is calculated to be the maximum amount of pollutions from phosphorus, nitrogen and sediments a water body can take on in a day before the water is impaired and we won’t have clear water with healthy grasses and abundant aquatic life in our streams, rivers, estuaries and the Bay.
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.
When the TMDL was first issued in 2010 the six states and Washington DC were required to submit the first version of the implementation plan or WIP by November of 2010, the next revision of the WIP was due in August 2012. The third and hopefully final version of the WIP is due in August 2018 and will have a more focused involvement with local entities like the county, Soil and Water Conservation Districts, towns and HOAs. These WIPs lay out a series of pollution control measures that need to be put in place by 2025. 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 going forward.
The WIPs have been responsible for a series of initiatives. Point source pollution loads from waste water treatment plants have been significantly reduced due to a series of plant improvements and expansions (many planned before the WIP) that will back off a little as population growth occurs in the service areas. An over sized waste water treatment plant is simply more effective during storm events and surges. As has been discussed in earlier blog posts we have gotten all the benefit from improvements in wastewater treatment that we are going to get. Going forward we will need to reduce nutrient and sediment pollution coming from urban and suburban stormwater. In addition, thought sediment loads from agriculture have decreased, the large agricultural land area of Virginia remains a primary source of sediment and further reductions are needed to meet the TMDL goals. Implementation of agricultural best management practices are the best method of achieving this goal.
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