MS4 Permit

Peters Township, located within Washington County, covers 19.8 square miles and has a population of approximately 23,000 (as of 2019). The municipality is primarily residential, agricultural, and commercial activity.

Peters Township (as well as many other urbanized areas throughout the state and country) is required by the Pennsylvania Department of Environmental Protection (PaDEP) and the U.S. EPA to obtain an MS4 Permit for the purpose of discharging stormwater from its storm sewer system to surface waters. This MS4 Permit (which stands for Municipal Separate Storm Sewer System) was first obtained by the Township in 2003. The most recent MS4 Permit was issued in late 2018.


The goal of the permitting process is to improve surface water quality through the regulation of stormwater discharges, which can be affected by activities within the watershed. Below are several links to important stormwater related websites, along with multiple resident tips and educational materials regarding common activities potentially affecting water quality in Peters Township.


The Township discharges stormwater to Brush Run, Chartiers Creek, Little Chartiers Creek (Canonsburg Lake), Peters Creek, and Piney Fork watersheds. Of those watersheds, Brush Run has a Total Maximum Daily Load (TMDL) for sediment and phosphorus. Peters Creek, Piney Fork, Little Chartiers Creek (Canonsburg Lake), and Middle Chartiers Creek do not have TMDLs, but are listed as impaired by the PaDEP for various reasons.

The Township intends to reduce the discharge of such pollutants to these waterways by the six required Minimum Control Measures (MCM)s and the associated Best Management Practices (BMP)s outlined in the MS4 permit. Additionally, Pollution Reduction Plan (PRP) / TMDL Plans have been developed for various watersheds and are part of our general MS4 permit PAI136134.

Plan Documentation

The Township has enacted plans for each of the six MCMs that specifically describe our goals, implementation, and evaluation of each MCM. Documentation for the completion of the required action items will be maintained by the Engineering Department and reviewed for our Annual Progress Reports to the PaDEP.

Guidelines for Maintaining Streams in Your Community

DEP wants to help Pennsylvania communities complete all necessary stream work in a way that is environmentally-responsible, reduces the likelihood of future flooding problems, and complies with regulations.  When in doubt, contact PaDEP for assistance before you start stream work projects.