Final TMDLs Approved by EPA: Bynum Run

Bynum Run is a free flowing stream that originates in the town of Forest Hill, northwest of the City of Bel Air, in Harford County, Maryland and flows 14 miles in a southeasterly direction until it empties into the tidal Bush River. The watershed is located in the Bush River sub-basin of the Chesapeake Bay watershed entirely within Harford County, Maryland and covers approximately 14,583 acres. The main transportation corridors in the watershed are the Maryland-Route 924 corridor, which runs along the west side of the watershed, and the Interstate-95 corridor which crosses the southern portion of the watershed. There is one “high quality”, or Tier II, stream segment (Benthic Index of Biotic Integrity (BIBI) and Fish Index of Biotic Integrity (FIBI) aquatic life assessment scores > 4 (scale 1 – 5)), which is unnamed, located within the watershed (the southeastern portion) requiring the implementation of Maryland’s antidegradation policy. Also, approximately 0.03% of the watershed area is covered by water (i.e., streams ponds, etc.). The total population in the watershed is nearly 78,540. 

MDE has identified the waters of the Bynum Run watershed on the State’s 2008 Integrated Report as impaired by sediments (1996), nutrients – nitrogen and phosphorus (1996), impacts to biological communities (2002), and polychlorinated biphenyls (PCBs) (2006). The designated use of the Bynum Run mainstem and its tributaries is Use III (Nontidal cold water).

The TMDL, available below, addresses the 1996 sediments listing, for which a data solicitation was conducted, and all readily available data from the past five years were considered. The TMDL sets the maximum load limit for sediments, and provides load allocations to point and nonpoint sources. A Water Quality Analysis (WQA) for eutrophication to address the nutrients listing (nitrogen and phosphorus) was approved by the EPA in 2007. In the 2012 Integrated Report, the listing for impacts to biological communities will include the results of a stressor identification analysis, and the PCBs listing will be addressed at a future date.

Total Maximum Daily Load of Sediment in the Bynum Run Watershed, 
Harford County, Maryland

(Approved on September 30, 2011)

EPA's Decision Letter EPA's Decision Letter 
(Does not include MDE's requested revisions)
MDE's Edits to EPA's Decision Letter MDE's Decision Letter Edits (35KB)
Main Report Bynum_Sed_TMDL_Final  (1,727KB)
Point Source Technical Memorandum Bynum_Sed_TMDL_PS_techmemo_Final (21KB)
Nonpoint Source Technical Memorandum Bynum_Sed_TMDL_NPS_techmemo_Final (15KB)
Comment Response Document Bynum_Sed_CRD_Final (33KB)

Additional Supporting Information

Biological Stressor Identification Bynum Run Watershed Report (581KB)
Biological Stressor Identification Methodology (459KB)
Nontidal Sediment TMDL Methodology Report (361KB)
Addendum to the Nontidal Sediment TMDL Methodology Report (23KB)


Contact Information

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