Final TMDLs Approved by EPA: Conococheague Creek

The Conococheague Creek watershed is located in both Maryland (MD) and Pennsylvania (PA) with a drainage area of 568 square miles (363,567 acres).  The majority (88.4%) of the watershed is in PA (in Franklin, Adams, Cumberland and Perry Counties) with a portion in Washington County, MD.

Conococheague Creek and its tributaries flow through several towns including Chambersburg, Greencastle and Mercersburg in PA and Williamsport in MD.  The headwaters of Conococheague Creek originate approximately 13 miles east of Chambersburg, PA.  Passing through Chambersburg it continues flowing southwest through PA and into MD and finally empties into the Potomac River near the town of Williamsport.  The tributaries of Conococheague Creek in MD include Semple Run, Meadow Brook, Rush Run, Toms Run, and Rockdale Run.

The Maryland Department of the Environment (MDE) has identified Conococheague Creek and its tributaries in the State of Maryland’s (MD) 303(d) List as impaired by fecal bacteria (listed in 2002), high pH (listed in 2002) and sediments (listed in 1996).  Conococheague Creek and the tributaries Meadow Brook, Troupe Run, and Rush Run have also been identified as impaired by impacts to biological communities (listed in 2004).  Conococheague Creek and all its tributaries have been designated as Use IV-P (Recreational Trout Waters and Public Water Supply).  See Code of Maryland Regulations (COMAR)  The document available below, establishes a TMDL for fecal bacteria in the Conococheague Creek watershed that will allow for attainment of the beneficial use designation of primary contact recreation.  The listings for pH, sediments, and impacts to biological communities will be addressed in separate TMDL documents. 

Revised Final Document

As a result of the permit renewal (13-DP-3229) processing, an update is being made to the fecal bacteria TMDL approved by USEPA on 05/07/2009.  This facility was not included in the TMDL and so, the facility is being added to the TMDL allocations.  This addition would shift some of the allocation from the stormwater wasteload allocation (SW-WLA) to the wastewater wasteload allocation (WWTP-WLA).  This reallocation of loads results in an overall decrease in the SW-WLA of 0.1%.  Within the subwatershed of interest, the additional decrease of the SW-WLA would be 1.3%.  The reallocation of the wasteload allocations does not affect the nonpoint source load allocation (LA) or the overall TMDL. The revised TMDL document was available for public review from February 2, 2015 through March 5, 2015.  No comments were received related to the TMDL.

Total Maximum Daily Loads of Fecal Bacteria for the Conococheague Creek Basin in Washington County, Maryland

(Approved on May 7, 2009)

​Comment Response Document for Revised Report CRD_ConococheagueCreek_fc_revised.pdf (9KB)
Revised Report TMDL_ConococheagueCreek_fc.pdf (7019KB)
EPA's Decision Letter

EPA's Decision Letter

Main Report TMDL_ConococheagueCreek_fc.pdf (2228KB)

Comment Response Document

CRD_ConococheagueCreek_fc.pdf (9KB)


Contact Information

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