The Antietam Creek watershed is located in both Maryland (MD) and Pennsylvania (PA) with a drainage area of 291 square miles (186,166 acres). The majority (64%) of the watershed is in Washington County, MD with portions in Franklin and Adams Counties in PA.
The main metropolitan area, Hagerstown, is centrally located along the western edge of the watershed. Antietam Creek and its tributaries flow through several small towns including Mount Alto and Waynesboro in Pennsylvania and Smithsburg, Boonsboro and Sharpsburg in Maryland.
The headwaters of Antietam Creek originate south of Waynesboro, PA with the confluence of East and West Branch Antietam Creek. It continues flowing southwest past Hagerstown, MD then through Antietam National Battlefield in Sharpsburg, and empties into the Potomac River near the town of Antietam.
The tributaries of Antietam Creek include, West Branch Antietam Creek, East Branch Antietam Creek, Little Antietam Creek (north), Marsh Run, Hamilton Run, Landis Spring Branch, Beaver Creek, Little Antietam Creek (south), and Sharmans Branch. The East and West Branches of Antietam Creek are located almost entirely in PA. Marsh Run flows through both PA and MD. The other tributaries are located entirely in MD.
The Maryland Department of the Environment (MDE) has identified Antietam Creek and its tributaries in the State of Maryland’s 303(d) List as impaired by low dissolved oxygen, nutrients, and sediments (all listed in 1996), fecal bacteria (listed in 2002) and impacts to biological communities (listed in 2002). Antietam Creek and its tributaries have been designated as Use IV-P (Recreational Trout Waters and Public Water Supply). Beaver Creek, Marsh Run, Little Antietam Creek and their tributaries have been designated as Use III-P (Nontidal Cold Water and Public Water Supply). See Code of Maryland Regulations (COMAR) 26.08.02.08Q. The document available below establishes a TMDL for fecal bacteria in the Antietam Creek watershed that will allow for attainment of the beneficial use designation of primary contact recreation. A TMDL for Biochemical Oxygen Demand, addressing the low dissolved oxygen listing, was approved by EPA in 2002. The listings for nutrients, sediments and impacts to biological communities will be addressed in separate TMDL documents. MDE monitored the Antietam Creek watershed from 2002-2003 for fecal bacteria. A data solicitation for fecal bacteria was conducted by MDE in 2003, and all readily available data from the past five years were considered.
EPA's Decision Letter
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