Final TMDLs Approved by EPA: Upper and Middle Chester River

The Upper Chester River Watershed is located within Kent and Queen Anne’s Counties, Maryland, with its headwaters in New Castle and Kent Counties, Delaware.  The Middle Chester River is located within Kent and Queen Anne’s Counties.  The Upper, Middle and Lower Chester Rivers make up the Chester River from its confluence with the Bay to its headwaters at New Castle.  The Upper and Middle Chester Rivers are approximately 32.2 kilometers (20 miles) in length, from the downstream extent to the upper reaches of the headwaters.  The Upper Chester River is approximately 16.9 kilometers (10.5 miles) and the Middle Chester River is approximately 15.3 kilometers (9.5 miles) in length.  The Upper Chester River extends from the headwaters downstream to the confluence with Foreman Branch, and the Middle Chester extends from that point downstream to the confluence with Southeast Creek.

The Upper Chester River was first identified on the State’s 1996 303(d) list as impaired by nutrients, sediments, and bacteria, with listings added in 2002 for evidence of biological impacts, and in 2004 for methylmercury in fish tissue in one of the basin’s impoundments (Millington Wildlife Management Ponds).  The sediment, bacteria, biological, and methylmercury in fish tissue impairments will be addressed separately.

The Middle Chester River was first identified on the State’s 1996 303(d) list as impaired by nutrients, sediments, and bacteria.  In 2002, poly-chlorinated biphenyls (PCBs) in fish tissue and evidence of biological impacts were added, with additional subbasins listed as impaired by evidence of biological impacts in 2004.  TMDLs to address the nutrient and sediment listings of Urieville Community Lake, an impoundment within the Middle Chester Watershed, were submitted and approved in 1999; the sediment, bacteria, PCBs in fish tissue and biological impacts will be addressed separately.  The document, available below, establishes TMDLs for nitrogen and phosphorus in the Upper and Middle Chester Rivers.

The U.S. Environmental Protection Agency (EPA) approved the TMDL on November 28, 2006.  However, a request for edits to the Approval Letter and Decision Rationale for this TMDL have been made.  Results from this request are available as of 2/25/08.  Please see EPA's Region 3 website for the approval letter and decision rationale.

In 2013, Genovique Specialties Corp. applied for a permit to discharge within the watershed.  This facility was previously known as Velsicol Chemical Corporation and was included in the calibration of the TMDL but not given an allocation.  As a result of the permit request, two changes occurred to the Middle Chester River phosphorus waste load allocations (WLAs).  To allow the Genovique facility a regulated discharge, part of the allocation for the Chestertown Foods, Inc. facility, which is located within the same model segment as the Chestertown Foods discharge, was redistributed (see Addendum for details).  The reallocation did not affect the load allocation (LA) or the overall TMDL.  The revised point source technical memorandum and addendum were available for public comment from October 24, 2013 through November 25, 2013.  No comments were received.

Revised Final Document for Public Comment

The Kent County Department of Public Works, Water and Wastewater Services, 709 Morgnec Road, Suite 201, Chestertown, MD 21620 applied for revocation of the current Worton – Butlertown Wastewater Treatment Plant permit (State Discharge Permit 13-DP-2109) and reissuance of the permit to discharge on a year-round basis an annual average of 250,000 gallons per day (gpd) of treated domestic wastewater from Worton - Butlertown Wastewater Treatment Plant located at 25310 Chinquapin Road, Worton, MD 21678 to an unnamed tributary of Morgan Creek, which is designated as Use I waters – protected for water contact recreation and nontidal warm water aquatic life. Continued authorization to discharge an annual average of 195,000 gpd of treated domestic wastewater to groundwaters of the State at 24530 Porters Grove Road in Worton, MD 21678, via a spray irrigation system was also requested in the application. The permit was previously renewed on November 1, 2015 as a seasonal discharge.

No TN and TP waste load allocation (WLA) for Worton - Butlertown WWTP for the period from May 1 to October 31 (growing season) is included in the Nutrient TMDL for Middle Chester River approved by EPA in November 28, 2006.  As a result of this permit, an update to the Middle Chester River Nitrogen and Phosphorous TMDL Point Source Technical Memorandum is being made. 

To assign the maximum loading rates of 1,816 lbs TN and 90 lbs TP for the period from May 1 to October 31, Worton - Butlertown WWTP will receive a portion of the allocation originally assigned to the Chestertown Foods Inc. facility (NPDES # MD0002232). The growing season WLA originally assigned to Chestertown Foods Inc. facility were 4,742 lbs TN and 1,000 lb TP. The termination of Chestertown Foods Inc, facility and removal of this discharge from the TMDL, will result in an overall reduction to the growing season WLAs under this TMDL. In addition, the annual TP WLA for Worton -Butlertown WWTP will be reduced from 678 lbs/yr to 228 lbs/yr. The revised point source technical memorandum is available for public comment on the Department’s website at  The reallocation of the WLAs does not affect the nonpoint source allocations (LAs) or the overall TMDL.

The revised point source technical memorandum is available below, for public comment from August 30, 2018 through October 1, 2018. Copies of the document are available below or by contacting Ms. Melissa Chatham at MDE/WSA, Washington Blvd, Baltimore, MD 21230, or by telephone at 410.537.3937;(outside the Baltimore area, dial 1.800.633.6101 x3937). Written comments concerning the revised document may be submitted the Department on or before October 1, 2018 and should be sent to Ms. Chatham at the above address or emailed to


Total Maximum Daily Loads of Nitrogen and Phosphorus for the Upper and Middle Chester Rivers in Kent and Queen Anne's Counties, Maryland

Approved on November 28, 2006

​2018 Revised Point Source Technical Memorandum TMDL_PS_TechMemo_revised_final_2018.pdf
Comment Response Document TMDL_Chester_CRD_2013_revision.pdf
Addendum TMDL_Addendum_Chester_River_nutrient.pdf
2013 Revised Point Source Technical Memorandum TMDL_PS_TechMemo_revised_final.pdf
EPA's Decision Letter EPA's Decision Letter
Main Report TMDL_final_Chester_main_nuts.pdf (1274 KB)
Appendices A-B TMDL_final_Chester_Appen_A_B.pdf (154 KB)

Appendix C

TMDL_final_Chester_Appen_C.pdf (1942 KB)
Appendix D TMDL_final_Chester_Appen_D.pdf (149 KB)
Appendix E TMDL_final_Chester_Appen_E.pdf (314 KB)
Point Source Tech Memo TMDL_final_Chester_PS_TechMemo.pdf (18 KB)
Nonpoint Source Tech Memo TMDL_final_Chester_NPS_TechMemo.pdf (14 KB)
Comment Response Document TMDL_final_Chester_CRD.pdf (5 KB)

Additional Supporting Information

Water Quality Model Report Chester_WQ_modeling_report.pdf (1492KB)
Water Quality Model Report Appendices Chester_WQ_modeling_report_appen_4.pdf (9098KB)

Chester_WQ_modeling_report_appen_5.pdf (6300KB)
Watershed Model Report Chester_Watershed_modeling_report.pdf (3079KB)


Contact Information

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