Final TMDLs Approved by EPA: Patuxent River Upper

The Maryland Department of the Environment (MDE) has identified the waters of the Maryland (MD) 8-digit Patuxent River Upper watershed on the State’s 303(d) List [Category 5 of the Integrated Report of Surface Water Quality in Maryland (Integrated Report)] as impaired by nutrients (listed in 1996, revised in 2008 to phosphorus), sediment (1996), fecal bacteria (2008), and impacts to biological communities (listed in 2002, 2004 and 2006).  Cash Lake, an impoundment in the Patuxent River Upper watershed, was listed in 2004 for methylmercury in fish tissue.  The waters of the MD 8-digit Patuxent River Upper watershed have been designated as Use I (Water Contact Recreation, and Protection of Nontidal Warmwater Aquatic Life).  See Code of Maryland Regulations (COMAR)>

The portion of the MD 8-digit Patuxent River Upper watershed listed as impaired by fecal bacteria begins at the confluence with Little Patuxent River and ends at the crossing of Queen Anne Bridge Road.  The watershed is located in the Patuxent River region of the Chesapeake Bay watershed within Maryland.  The watershed covers portions of Anne Arundel and Prince George’s Counties.  It also includes portions of the towns of Bowie, Davidsonville, and Mitchellville.  The listed watershed area covers 28.7 square miles (18,362 acres), with an additional 342.1 square miles (218,951 acres) draining from upstream areas.

The document available below establishes a TMDL for fecal bacteria in the Patuxent River Upper watershed, from Queen Anne Bridge Road to the confluence with Little Patuxent River, that will allow for attainment of the beneficial use designation of water contact recreation.  The listings for sediment, impacts to biological communities, and methylmercury will be addressed in separate TMDL documents.  The listing for phosphorus was addressed with a Water Quality Analysis in 2007.  MDE monitored the Patuxent River Upper watershed from 2008-2009 for fecal bacteria.  A data solicitation for fecal bacteria was conducted by MDE in 2007, and all readily available data from the past five years were considered. 

Total Maximum Daily Loads of Fecal Bacteria for the Patuxent River Upper Basin in Anne Arundel and Prince George’s Counties, MD

(Approved on August 9, 2011)

EPA's Decision Letter EPA's Decision Letter
Main Report

TMDL_Patuxent_River_Bacteria.pdf (1304KB)

Comment Response Document

CRD_Patuxent_River_Bacteria.pdf (7KB)

Contact Information

Please direct questions or comments concerning this project to Maryland's TMDL Program at (410) 537-3818.