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    Program Updates

    • Draft PAG-13 General Permit for Discharges of Stormwater from Small Municipal Separate Storm Sewer Systems Available for Public Comment

      The availability of the draft PAG-13 General Permit for public comment was announced in the January 18, 2025 edition of the Pennsylvania Bulletin ([55 Pa.B. 601]). Access the draft General Permit and related documents in DEP’s eLibrary. DEP is also soliciting feedback on the draft Maximum Extent Practicable (MEP) Calculator spreadsheet (XLSM) and its instructions (PDF).  The MEP Calculator spreadsheet would be used when preparing renewal Notices of Intent (NOIs).

      A 60-day comment period is being provided for the submission of written comments on the draft PAG-13 General Permit and associated documents. Commenters are encouraged to submit comments using DEP’s online eComment system. Alternatively, written comments can also be submitted by email to ecomment@pa.gov or by mail to the Department of Environmental Protection, Policy Office, Rachel Carson State Office Building, P.O. Box 2063, Harrisburg, PA 17105-2063. Comments, including comments submitted by email, must include the commenter’s name and address and be received by March 19, 2025.

      A brief presentation on the draft PAG-13 has been posted to Clean Water Academy. This presentation includes a summary of the changes proposed in the draft PAG-13 but is not intended to provide a comprehensive  review of all components of the permit. MS4 permittees, consultants, and other interested persons are encouraged to review all of the PAG-13 documents listed above for an in-depth understanding of the draft permit. Detailed training will be developed at a later date to accompany the final PAG-13.
    • PAG-13 General Permit for Discharges of Stormwater from Small Municipal Separate Storm Sewer Systems Extension

      The availability of the current NPDES PAG-13 General Permit has been extended until the PAG-13 is reissued (see Pennsylvania Bulletin (54 Pa.B. 20). The deadlines contained in the PAG-13 General Permit, including the dates by which implementation of Pollutant Reduction Plans (PRPs) and Pollutant Control Measures (PCMs) must be achieved, have not been extended. The administrative extension of PAG-13 does not extend any deadlines associated with waivers. More information on the PAG-13 extension can be found in the MS4 FAQ document (see FAQs # 78 – 82).

    Background

    Municipalities and other entities such as universities and prisons that meet certain criteria must obtain NPDES permit coverage for discharges of stormwater from their municipal separate storm sewer systems (MS4s). In Pennsylvania, there is one Large MS4, one Medium MS4, and 1,059 Small MS4s. Additional Small MS4s may be designated by DEP when determined to be appropriate using DEP’s designation criteria.

    MS4s must apply for NPDES permit coverage or a waiver if they are located in an census-designated Urban Area that meets EPA’s automatic designation criteria for small MS4s, or if they are designated as needing a permit by DEP. EPA has posted Urban Area Maps from the 2020 census data.

    For NPDES permits issued after 2017, MS4s that discharge to surface waters impaired for certain pollutants or that discharge to waters in the Chesapeake Bay watershed were required to develop Pollutant Reduction Plans (PRPs) or TMDL Plans. See the PRP/TMDL Plans webpage for further information.

    NPDES Permits

    Small MS4s that are required by federal regulations to obtain NPDES permit coverage may, if eligible, apply for coverage under the NPDES General Permit for Stormwater Discharges from Small MS4s (PAG-13) (3800-PM-BCW0100). During the period of administrative extension, the Department may not authorize new coverage under PAG-13. Small MS4s that are ineligible for PAG-13 General Permit coverage may apply for an individual permit (3800-PM-BPNPSM0200).

    Permit coverage is generally for a 5-year term. To renew coverage for a new term, MS4 permittees must submit an individual permit application or a NOI to discharge under the statewide General Permit prior to the expiration date of coverage, as specified in the permit. The MS4 can, if it chooses, elect to apply for an individual NPDES permit in lieu of continued coverage under the reissued General Permit.

    DEP has developed a reporting tool that can be used to search NPDES-permitted and waived MS4s in Pennsylvania.

    Compliance

    DEP's regional offices inspect MS4s to determine if the MS4 is meeting its permit obligations. The inspections are documented on a MS4 inspection report. DEP also reviews the Annual Status Reports (3800-FM-BCW0491) submitted by MS4s to DEP.

    Contact Us

    For questions on MS4 NPDES permits and compliance in Pennsylvania, contact DEP’s Bureau of Clean Water (BCW) at RA-EPPAMS4@pa.gov or 717-787-5017.