MS4

NPDES MS4 Permit from DEP

As part of the Clean Water Act, the U.S. Environmental Protection Agency (EPA) has developed stormwater management regulations to improve water quality. The Township was required to apply for a National Pollutant Discharge Elimination System (NPDES) permit which is administered through the Pennsylvania Department of Environmental Protection (DEP). This permit is a 5-year program which began in 2003. The permit is broken up into 6 control measures which include: Public Outreach and Education, Public Participation and Involvement, Illicit Discharge Detection & Elimination, construction site stormwater runoff control, Post-Construction Storm Water Management in New Development and Redevelopment, and Pollution Prevention and Good Housekeeping for Municipal Operations and Maintenance.

Learn More About MS4

Learn more about stormwater management and pollution prevention!

Illicit Discharge Information

What is an illicit discharge?

Illicit discharges are any discharge into a storm drain system that is not composed entirely of stormwater. Illicit discharges contain contaminants such as bacteria, heavy metals, and viruses that are polluted into receiving waterbodies. Under the Federal Clean Water Act, discharge of storm water is regulated by the National Pollutant Discharge and Elimination System (NPDES). The MS4 map identifies outfalls as the location where stormwater flows enter a surface waterway and may or may not involve a physical structure such as a pipe. These discharges include, but are not limited to:

  • Septic tank seepage
  • Improper disposal of commercial and industrial waste
  • Pesticides and fertilizers
  • Laundry wastewater
  • Household waste
  • Sump pump discharges
  • Improper waste oil disposal

Click here for the Illicit Discharge Ordinance - HR-364(PDF, 92KB)

Contact the Engineering Department to report the occurrence of any dumping or seeping of discharges described above or seeming suspicious.

Other Reporting: Please refer to the table below describing types of discharges and responsive parties for any discharges that seem to threaten public health and/or safety.

Type of Discharge  Responsive Party Contact Information 
  • Immediate danger to public health, safety, or environment;
  • The presence of smoke, smells of gas, chemicals or gas leaks entering the storm system;
  • Any suspected unlawful activity;
  • Visible dumping of toxic or suspicious waste in storm systems (paint, trash, etc.);
  • Report of sheen across a river or creek bed.
 Township Police
  • Dry weather outfall flows;
  • Clogged or leaking sanitary sewer lines;
  • Sewage smell;
  • Illegal discharges into creeks or storm drains;
  • Observations of illicit discharges are identified: color changes, smells, debris, etc.
  • Pet waste, grass clippings or pool water discharging into storm system;
  • Observations of industrial waste (restaurants, carpet/dry cleaners, etc.) discharging into storm system.
 Public Works Director and/or Engineering Department 

Public Works Director - Darin Fitzgerald

Township Engineer - Stephen Burgo, P.E.
  • Immediate danger to public health, safety or environment;
  • The presence of smoke, gas smells, gas leaks;
  • Public report of gasoline or other petroleum products entering the storm sewer.
  Fire Companies

Berwyn Fire Company

Paoli Fire Company

Radnor Fire Company
  • Immediate danger to public health, safety or environment
  Emergency Responders/Police
  • Gasoline or any suspected broken infrastructure;
  • Public report of gasoline or other petroleum products entering the storm sewer.
 PECO 
  • Suspected broken water mains.
 AQUA PA 
  • Debris and flooding carrying storm discharge on the roadway.
 PennDOT and/or PA Turnpike

October 19, 2021 - Message from the Township Engineer

PADEP approved the Township’s Pollution Reduction Plan (PRP) and Municipal Separate Storm Sewer System (MS4) Permit in August 2021. The permit went into effect on 8/1/21 and the permit cycle will run through 7/31/26.  During the 5-year permit cycle, the Township will be obligated to plan, design, and install various Engineering Stormwater Control Measures or Best Management Practices (BMPs), as well as increase its Public Works Operations and Maintenance procedures, such as Street Sweeping and Inlet Cleaning, to comply with the mandatory 10% sediment load reductions in our various Township Watersheds. 

The Township will continue to enforce its existing Stormwater Management Ordinance (HR-375), which requires redevelopment and development projects in excess of 499-sf of impervious coverage being installed to provide a SWM Plan and install on-site stormwater controls to reduce runoff associated with the increased project impervious surfaces.  In 2022, the Township will be required to adopt some updates into its Stormwater Management Ordinance (HR-375) for MS4 being developed by Chester County, as required by PADEP.  

Over the next 5-years, the Township Engineering and Public Works Departments will be working on Capital Construction Projects, as well as Enhanced Operations and Maintenance Procedures that will help the Township with compliance with the PADEP MS4 Permit requirements. 

In 2022, work is being planned to expand the existing Stormwater Management Basin at Strafford Park in the Gulph Creek Watershed and coordinate and partnering with the Valley Creek Restoration Partnership (VCRP) for various headwater Stormwater Infiltration BMPs in the Crabby Creek Watershed.  These projects will work to benefit not only our MS4 compliance requirements, but also help with capturing, treating, and reducing runoff to downstream residents, businesses and property owners in Tredyffrin Township.  Tredyffrin Township has been speaking with Radnor Township, who is interested in partnering on the Strafford Park Basin Expansion Project to increase the overall flood reduction benefits to both Tredyffrin and Radnor Township residents. 

Finally, PADEP will require Annual Reports to be submitted to their offices on the Engineering and Public Works activities starting in September 2022.

PADEP FINAL NPDES Permit 2021

PADEP Draft NPDES Permit - MS4 Update - April 30, 2021

Final Pollutant Reduction Plan - March 22, 2021

2020 Pollutant Reduction Plan

Tredyffrin Township is required to develop and implement a Pollution Reduction Plan (PRP) for Municipal Separate Stormwater System (MS4) discharges to impaired surface waterways within the Urbanized Area of the township, including Valley Creek, Trout Creek, Little Valley Creek, Gulph Creek, Crow Creek, Darby Creek, and Crum Creek. The PRP is a requirement and condition of the application for a National Pollution Discharge Elimination System (NPDES) MS4 Permit to the Pennsylvania Department of Environmental Protection (PADEP). The MS4 Permit authorizes the township to discharge stormwater to surface waters of the Commonwealth. This PRP Plan has been updated based on comments from PADEP and the most current guidance available.

To review the proposed plan, please click on the links below:  

Any comments on the PRP should be provided in written format either in person at the Township Building or via email to the Township Engineering Department at EngineeringDept@tredyffrin.org.

2017 Pollutant Reduction Plan

2017 - Pollutant Reduction Plan Available for Public Comment – Tredyffrin Township - NOTICE IS HEREBY GIVEN that the Tredyffrin Township Pollutant Reduction Plan (PRP) will be available for public review and comment for a 30-day comment period beginning on Wednesday, November 8, 2017 through Friday, December 8, 2017. The plan will be available for review and comment at the Tredyffrin Township Municipal Building, 1100 DuPortail Road, Berwyn, PA 19312. Tredyffrin Township has developed this plan in order to meet the requirements of the 2018-2023 National Pollutant Discharge Elimination System (NPDES) Individual Permit Application to discharge stormwater from the Municipal Separate Storm Sewer System (MS4). Under the new MS4 permit, Tredyffrin Township is required to reduce pollutants to surface waterways of the township including Little Valley Creek, Valley Creek, Gulph Creek, Crum Creek, Darby Creek, Crow Creek, and Trout Creek. All comments should be submitted in writing to the Township no later than 5:00pm, December 8, 2017.

   

The pages in this department are set up to address some of these issues and communicate with Township residents and businesses about different things that affect stormwater. If you have any additional questions, please contact the Engineering Department at EngineeringDept@tredyffrin.org or 610-644-1400.

 

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