The City of New York (NYC) is considered a large MS4 subject to the Phase I Stormwater Permitting requirements specified in the Clean Water Act. This page contains the State Pollutant Discharge Elimination System (SPDES) permit that authorizes discharges of stormwater from the large municipal separate storm sewer systems (MS4s) as defined in Title 40 of the Code of Federal Regulations (40CFR 122.26(b)(4)), currently existing within the jurisdictional boundaries of NYC (urbanized area), and limited to those MS4 outfalls owned or operated by New York City. The intent of this SPDES permit is to manage urban sources of stormwater runoff to protect overall water quality and improve water quality in impaired waters as part of a comprehensive integrated planning approach that considers non-MS4 sources and planned controls for those sources.
Other information contained on this page is the factsheet and responsive summary that accompany the permit, and all public comment letters that were received on the permit.
This permit was issued on July 15, 2022, and became effective on August 1, 2022.
- 2022 NYC MS4 Permit (NY-0287890) Fact Sheet (PDF) - July 15, 2022
This document describes the substantive changes made to the official MS4 permit issued on August 1, 2015 as reflected in the renewed permit.
- 2022 NYC MS4 Permit (NY-0287890) Responsiveness Summary (PDF) - July 15, 2022
This document includes the Department's response to all comments received during the public comment periods on the draft Municipal Separate Storm Sewer Systems (MS4) of NYC (NY-0287890).
- The General Permit for Stormwater Discharges from Municipal Separate Storm Sewer Systems, GP-0-15-003 (PDF)
- Resources for SWMP development and implementation can be found on the MS4 Toolbox page