Erosion and Sediment Control (ESC) BMP Expert Panel Report
Recommendations of the Expert Panel to Define Removal Rates for Erosion and Sediment Control Practices.
Description
Construction sites are estimated to comprise about 84,500 acres of the watershed, but deliver about 16% of the total annual sediment load from the urban sector to the Bay, based on current model estimates. An expert panel was convened to review past estimates of the sediment and nutrient removal rates associated with erosion and sediment control (ESC) practices.
In recent years, all of the Bay states have strengthened their ESC requirements for construction sites, through more sophisticated practice specifications, new technology, and more stringent inspection and enforcement procedures. In 2011, West Virginia requested a new BMP review panel for enhanced ESC practices, and proposed an interim efficiency for these enhanced practices (See Appendix E). West Virginia noted that the more stringent design and inspection requirements contained in their most recent construction general permit should produce higher sediment and nutrient removal efficiencies than the existing rates of 25% (TN) and 40% (TSS and TP).
Based upon a review of current literature and monitoring data, the Panel devised a four-tier system to classify the overall sediment removal performance of ESC practices based on past, current and future ESC implementation. Recommendations from the Expert Panel are outlined in this report.