Extension of NPDES General Permit (PAG-13) for Small Municipal Separate Storm Sewer Systems

September 27th, 2022

The PA Department of Environmental Protection (DEP) published notice on September 24, 2022 to extend for 24 months the availability of the current National Pollutant Discharge Elimination System (NPDES) General Permit for Discharges of Stormwater Discharges from Small Municipal Separate Storm Sewer Systems (MS4) (PAG-13). This notice does not extend any deadlines that are contained in the existing PAG-13, including the date by which implementation of Pollutant Reduction Plans and Pollutant Control Measures must be achieved.

The existing PAG-13 in effect at this time will expire on March 15, 2023. Persons who are operating under PAG-13 may continue to operate until March 15, 2025.  DEP is extending the availability of this permit to adequately address issues related to the renewal of PAG-13. During the period of administrative extension, DEP may not authorize new coverage under PAG-13.

 By extending the existing PAG-13, DEP, existing permittees and potential applicants will have additional time to consider and address the following:

• The 2020 ''urbanized areas'' defined by the United States Census Bureau have not yet been released. Without this information, it is unknown how the regulated planning area of existing PAG-13 permittees will change, or if additional MS4s will need PAG-13 coverage or waivers.
• With the goal of developing a long-lasting model for future permit terms that is based on robust public engagement, the Department intends to convene a PAG-13 workgroup in the coming months to gather feedback on permit requirements from the regulated community and other interested parties. The purposes of this workgroup include soliciting feedback on the requirements of the 2018 General Permit and discussing the feasibility of pollutant reduction requirements in future permit terms, including consideration of the meaning of ''maximum extent practi-cable'' for MS4s, as specified under the Federal Clean Water Act, and the extent to which collaboration with other MS4s can be achieved.

DEP is soliciting interest for participation in a workgroup to discuss and evaluate requirements to be incorporated into PAG-13 at the time of its renewal. Interested parties may request participation in the workgroup by sending an e-mail to DEP at by Tuesday, October 11, 2022. To keep the workgroup focused and productive, there will be a limited number of workgroup seats. Requesting participation does not guarantee a seat. However, members of the public will be able to provide input during the public comment period for the draft renewed PAG-13. DEP will notify selected workgroup members.

To access the General Permit and related documents, visit the DEP's eLibrary web site at (select Permit and Authorization Packages, then Clean Water, then PAG-13 NPDES General Permit for Stormwater Discharges from Small Municipal Separate Storm Sewer Systems (MS4S) 3800-PM-BCW0100).

For more information on municipal stormwater requirements, visit DEP’s Municipal Stormwater website at

Questions regarding the PAG-13 General Permit can be directed to Jamie Eberl, PE, at or (717) 772-4058.