Final TMDL Approved by EPA: Piscataway Creek Watershed

The Piscataway Creek watershed is located entirely within Prince George’s County, Maryland. Headwaters originate to the west and east of Andrews Air Force Base (AFB) in the vicinity of Camp Springs, Clinton and Woodyard. The base sits atop a north-south drainage divide, in the vicinity of the runways, that separates the Potomac River Basin to the west and the Patuxent River Basin to the east. The area surrounding Andrews AFB to the east is residential, commercial, light and heavy industrial, agricultural and some open land.  On the southwest side of Andrews AFB two branches join to form Tinkers Creek, the major tributary to Piscataway Creek. Surface water runoff flows into Tinkers Creek, to Piscataway Creek, and eventually into the Potomac River. From the southeast of Andrews AFB, the mainstem receives drainage from nearly 1,500 acres of the base and is partially redirected to a man-made lake (Base Lake) on base. The Piscataway Creek mainstem has two named tributaries: Dower House Branch to the northeast and Butler Branch to the southwest. There are several small unnamed tributaries supplying input to Piscataway Creek. The northern region of the Piscataway Creek watershed is the most developed; it is between Andrews AFB and Louise F. Cosca Regional Park. The southern region comprises the area between Louise F. Cosca Regional Park and Piscataway Creek drainage. The land use to the south is mostly forested, some open and row-crop agricultural land, residential, commercial, and light industrial. Butler Branch (tributary to Piscataway Creek) flows through Louise F. Cosca Regional Park and it forms a lake within the park. To the south the land is more forested and agricultural with the encroachment of rural development. Along Accokeek Road (Route 373) between Dyson Road and Bealle Road there are older homes with septic systems. To the south along Indian Head Highway (Route 210) there is extensive urban development and homes with septic systems.
The watershed is located on the western shore of the Coastal Plain region, one of three distinct eco-regions identified in the Maryland Department of Natural Resources Maryland Biological Stream Survey (MDDNR MBSS) Index of Biological Integrity (IBI) metrics. ​The total population in the Piscataway Creek watershed is approximately 10,900. There are two “high quality,” or Tier II, stream segments located within the Piscataway Creek watershed. Tier II segments are designated using MBSS data, and both the FIBI and BIBI values must be greater than 4.00 (on a scale of 1 – 5). Tier II segments require the implementation of Maryland’s anti-degradation policy, which is designed to prevent degradation of high quality waters. The policy requires a review of all permitted activities upstream of Tier II stream segments. 
The TMDL, available below, will ensure that watershed sediment loads are at a level to support the designated uses for the Piscataway Creek watershed, and more specifically, at a level to support aquatic life. 

Total Maximum Daily Load of Sediment in the Piscataway River Watershed, Prince George's County, Maryland

(Approved on October 3, 2019)

EPA's Decision Letter EPA's Decision Letter (3010KB)
​Fact Sheet Piscataway_Creek_Sed_TMDL_FactSheet.pdf (348KB)
Main Report

Piscataway_Creek_Sed_TMDL_final.pdf (1843KB)

Point Source Technical Memorandum Piscataway_Creek_Sed_TMDL_PS_TechMemo.pdf (236KB)
Nonpoint Source Technical Memorandum Piscataway_Creek_Sed_TMDL_NPS_TechMemo.pdf (217KB)
Comment Response Document Piscataway_Creek_Sed_TMDL_CRD.pdf (205KB)

Additional Supporting Information

Biological Stressor Identification Piscataway Creek Watershed Report (738KB)

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.