Back River Watershed in Baltimore County and Baltimore City, Maryland

Notice of Intent to Establish a TMDL for Sediment

Section 303(d) of the federal Clean Water Act (CWA) directs States to identify and list waters, known as water quality limited segments (WQLSs), in which current required controls of a specified substance are inadequate to achieve water quality standards.  For each WQLS, the State is required to establish a Total Maximum Daily Load (TMDL) of the specified substance(s) that the waterbody can receive without violating water quality standards, demonstrate that another program or action will achieve water quality standards, or demonstrate via the development of a Water Quality Analysis (WQA) that water quality standards for the specified substance(s) are currently being achieved.  The Maryland Department of the Environment (MDE) hereby gives notice of the public availability of a draft TMDL document for Sediment for Back River Watershed (basin code 02130901). This document was available for public review previously from June 15, 2017 through July 14, 2017.  However, due to a calculation error in the WLA, the TMDL and the report had been revised. Following EPA guidance, a second 30-day public comment period will be made available to the public for review and comment. Details are below.

The Maryland Department of the Environment (MDE) identified the non-tidal waters of the Back River watershed on the State’s 2014 Integrated Report as impaired by multiple pollutants including sediments, chlorides, sulfates, polychlorinated biphenyls, metals and nutrients. The Back River is associated with two assessment units in Maryland’s Integrated Report: a non-tidal 8-digit watershed (02130901) and an estuarine portion (Chesapeake Bay segment Back River Oligohaline). For more details about these listings, please see the TMDL report being made available for public comment. A data solicitation for TSS/sediment was conducted by MDE in September 2016, and all readily available data have been considered.
The TMDL sets the maximum load limit for the impairing substance.  The TMDLs also reflect load allocations to point sources, nonpoint sources and a margin of safety that accounts for uncertainty in the procedures used to estimate the TMDLs.  Once established by the State, the TMDLs will be subject to approval by the U.S. EPA.  The approved TMDLs will support measures needed to attain water quality standards in the Back River Watershed.
A 30-day public comment period for the draft document will take place from October 16, 2017 to November 14, 2017. Copies of the draft document have been placed in the Enoch Pratt Free Library (EPFL) – Herring Run Branch, 3801 Erdman Ave, Baltimore MD 21213; EPFL – Hamilton Branch, 5910 Harford Road, Baltimore, MD 21214; Baltimore County Public Library (BCPL) –Loch Raven Library, 1046 Taylor Ave, Towson, MD 21286; and the BCPL – Essex Branch, 1110 Eastern Blvd, Essex, MD 21221.  The draft document is also available on the Internet at web site or by contacting Ms. Melissa Chatham by mail at MDE/WSA, 1800 Washington Boulevard, Baltimore, MD 21230, or by telephone at 410-537-3937 (outside the Baltimore area, dial 1-800-633-6101 x3937).  Anyone wishing to review the draft documents and supporting information or needing technical information may contact Ms. Chatham during normal business hours. 
Written comments concerning the draft document may be submitted to the Department on or before November 14, 2017 and should be sent to Ms. Chatham at the above address or emailed to  All comments received during the comment period will be considered and the draft document may be revised accordingly prior to its submittal to EPA for approval.


Draft Total Maximum Daily Load of Sediment
in the Non-Tidal Back River Watershed,
Baltimore County and Baltimore City, MD

Fact Sheet Back_River_TSS_TMDL_fact_sheet.pdf (413KB)
Main Report Back_River_Sed_TMDL_PN.pdf (1,735KB)
Point Source Technical Memorandum Back_River_Sed_TMDL_PS_TechMemo.pdf (37KB)
Nonpoint Source Technical Memorandum Back_River_Sed_TMDL_NPS_TechMemo.pdf (26KB)

Additional Supporting Information

Biological Stressor Identification Back River Watershed Report (466KB)

Biological Stressor Identification Methodology (459KB)

Nontidal Sediment TMDL Methodology Report (361KB)

Addendum to the Nontidal Sediment TMDL Methodology Report (23KB)