DEPARTMENT OF NATURAL RESOURCES AND ENVIRONMENTAL CONTROL

Division of Water Resources

7 DE Admin. Code 7410

Statutory Authority: 7 Delaware Code,

Chapter 60 (7 Del.C. Ch. 60)

PROPOSED

REGISTER NOTICE

TMDLs for the Shellpot Creek and Naamans Creek Watersheds

1. Brief Synopsis of the Subject, Substance, and Issues

The Department of Natural Resources and Environmental Control (DNREC) is proposing to adopt Total Maximum Daily Loads (TMDLs) Regulations for nitrogen, phosphorous, and bacteria for the Shellpot Creek and Naamans Creek Watersheds. A TMDL sets a limit on the amount of a pollutant that can be discharged into a waterbody and still protect water quality. TMDLs are composed of three components including Waste Load Allocations (WLAs) for point source discharges, Load Allocations (LAs) for nonpoint sources, and a Margin of Safety (MOS) to account for uncertainties and future growth.

2. Possible Terms of the Agency Action

Following adoption of the proposed Total Maximum Daily Loads for the Shellpot Creek and Naamans Creek Watersheds, DNREC will develop a Pollution Control Strategy (PCS) to achieve the necessary load reductions. The PCS will identify specific pollution reduction activities and timeframes and will be developed in concert with Shellpot Creek and Naamans Creek Tributary Action Teams, other stakeholders, and the public.

3. Statutory Basis or Legal Authority to Act

The authority to develop a TMDL is provided by Title 7 of the Delaware Code, Chapter 60, and Section 303(d) of the Federal Clean Water Act, 33 U.S.C. 1251 et. seq., as amended.

4. Other Legislation That May be Impacted

None

5. Notice of Public Hearing and Comment

A public hearing will be held at 6:00 p.m., Wednesday, September 7, 2005, at the auditorium of Mt. Pleasant Elementary School, 500 Duncan Road, Wilmington, Delaware, 19809. The hearing record will close at the conclusion of the hearing. Please send written comments to Robert P. Haynes, Hearing Officer, DNREC, 89 Kings Highway, Dover, DE, 19901; facsimile: (302) 739- 6242; email: Robert.Haynes@state.de.us.

Additional information and supporting technical documents may be obtained by contacting Hassan Mirsajadi, Watershed Assessment Section, Division of Water Resources, Department of Natural Resources and Environmental Control, 820 Silver Lake Boulevard, Suite 220, Dover, DE 19904-2464, (302) 739-4590, facsimile: (302) 739-6140, email: (Hassan.Mirsajadi@state.de.us)

6. Prepared By:

John Schneider, Watershed Assessment Section, 739-4590

7411 TMDLs for Shellpot Creek, Delaware

1.0 Introduction and Background

1.1 Water quality monitoring performed by the Department of Natural Resources and Environmental Control (DNREC) has shown that the Shellpot Creek is impaired by high levels of bacteria and elevated levels of the nutrients nitrogen and phosphorous, and that the designated uses are not fully supported by water quality in the stream.

1.2 Section 303(d) of the Federal Clean Water Act (CWA) requires states to develop a list (303(d) List) of waterbodies for which existing pollution control activities are not sufficient to attain applicable water quality criteria and to develop Total Maximum Daily Loads (TMDLs) for pollutants or stressors causing the impairment. A TMDL sets a limit on the amount of a pollutant that can be discharged into a waterbody and still protect water quality. TMDLs are composed of three components, including Waste Load Allocations (WLAs) for point source discharges, Load Allocations (LAs) for nonpoint sources, and a Margin of Safety (MOS).

DNREC listed Shellpot Creek on several of the State’s 303(d) Lists and proposes the following Total Maximum Daily Load regulation for nitrogen, phosphorous and Enterococcus bacteria.

2.0 Total Maximum Daily Loads (TMDLs) Regulation for the Shellpot Creek, Delaware

Article 1. The nonpoint source nitrogen load from the area south of Business Route 13 shall be reduced by 35% (from the 2000-2003 baseline). This shall result in reducing the yearly-average total nitrogen load from 19.2 pounds per day to 12.5 pounds per day.

Article 2. The nonpoint source nitrogen load from the area north of Business Route 13 shall be capped at the 2000-2003 baseline level. This shall result in a yearly-average total nitrogen load of 89.4 pounds per day.

Article 3. The nonpoint source phosphorous load from the area south of Business Route 13 shall be reduced by 35% (from the 2000-2003 baseline). This shall result in reducing the yearly-average total phosphorous load from 2.0 pounds per day to 1.3 pound per day.

Article 4. The nonpoint source phosphorous load from the area north of Business Route 13 shall be capped at the 2000-2003 baseline level. This shall result in a yearly-average total phosphorous load of 5.7 pounds per day.

Article 5. The nonpoint source bacteria load shall be reduced by 74% from the 1998-2004 baseline level. This shall result in reducing a yearly-mean bacteria load from 3.7E+10 CFU per day to 9.0E+9 CFU per day.

Article 6. The bacteria load from Wilmington CSO 31 shall be reduced by 28% from the 1998-2004 baseline level. This shall result in reducing a yearly-mean bacteria load from 5.4E+10 CFU per day to 3.9E+10 CFU per day.

Article 7. Based upon water quality model runs and assuming implementation of reductions identified by Articles 1 through 6, DNREC has determined that, with an adequate margin of safety, water quality standards will be met in Shellpot Creek.

Article 8. Implementation of this TMDLs Regulation shall be achieved through development and implementation of a Pollution Control Strategy. The Strategy will be developed by DNREC in concert with a Shellpot Creek Tributary Action Team, other stakeholders, and the public.

9 DE Reg. 224 (08/01/05) (Prop.)