The Western Maryland TMDL for Low pH includes five watersheds: the Casselman River, Georges Creek, the Savage River, the Upper North Branch of the Potomac River, and Wills Creek. All five watersheds are in western Maryland; however, portions of Wills Creek and the Casselman River also flow through Pennsylvania. The headwaters of Wills Creek begin in Pennsylvania. The Casselman River flows through portions of Maryland and Pennsylvania and eventually flows into the Youghiogheny River. The Savage River, Georges Creek, and Wills Creek all flow into the Upper North Branch of the Potomac River. The North Branch of the Potomac flows along the southern edge of Maryland until the river reaches the Chesapeake Bay.
The Casselman River 8-digit Basin (basin code - 05020204) is impaired by impacts on biological communities (2002/2004 listing) and low pH (1996 listing). The Georges Creek 8-digit Basin (basin code - 02141004) is impaired by impacts on biological communities (2002 listing) and low pH (1998 listing). The Savage River 8-digit Basin (basin code - 02141006) is impaired by impacts on biological communities (2004/2006 listing). The Upper North Branch of the Potomac River 8-digit Basin (basin code - 02141005) is impaired by impacts on biological communities (2004 listing) and low pH (1996 listing). The Wills Creek 8-digit Basin (basin code - 02141003) was identified on Maryland’s section 303(d) list of impaired surface waters as impaired by impacts on biological communities (2002 listing) and nutrients (1996 listing). In addition to the 8-digit basin listings for low pH there are several 12-digit basin listings for low pH in George Creek, the Upper North Branch Potomac River, and Wills Creek.
Water quality monitoring data collected in all basins with pH listings in 2005 by the Maryland Department of the Environment (MDE) indicate that observed pH levels sometimes exceed water quality standards for 52 segments in the five watersheds included in the report available below. The pollutant loadings were classified by source, including acid mine drainage (AMD) and atmospheric deposition, and organic sources. In addition, a segment could be classified as having chronic or episodic acidification, with no identified source.
The TMDLs for Georges Creek (Mill Run) and Savage River (Aarons Run) were revised in 2010. In the revision to these TMDLs, discharges from the incorporation of two additional mining operations will increase flow and iron loading into the system without causing a violation of the pH water quality standard. Permit requirements ensure that discharges from these facilities do not violate pH water quality. Even though the iron loading associated with these facilities will increase the TMDLs and WLAs, for the streams in which they discharge, it will not result in any changes to the pH.
A 30-day public comment period for the draft revised document took place from June 4, 2010 to July 6, 2010. No comments were received. The EPA approved revised document is available below.
Western Maryland pH TMDLs for the Casselman River, Georges Creek, Savage River, Upper North Branch of the Potomac River, and Wills Creek WatershedsApproved on April 17, 2008Revised document approved on February 10, 2011
EPA's Decision Letter
EPA's Letter on Revised Final
Comment Response Document
Please direct questions or comments concerning this project to Maryland's TMDL Program at (410) 537-3818.
1800 Washington Boulevard, Baltimore, MD 21230