Do you Discharge into MS4? Do you need a SPDES permit?

A State Pollutant Discharge Elimination Permit (SPDES) is required to prevent harmful pollutants from being washed or dumped into MS4s or surface waters. A municipal Separate Storm Sewer System (MS4) is a system that discharges to Surface Waters of the State and is not part of a publicly owned wastewater treatment plant.

There are two kinds of SPDES permits:

  1. Industrial: If any industrial facility discharges stormwater into MS4s or into surface waters, it is required to obtain a SPDES permit in order to comply with NYSDEC regulations (GP-0-17-004);
  2. and Construction: NYSDEC also requires construction projects disturbing an acre or more of soil to obtain a SPDES permit from construction activities (GP-0-15-002)

New York City Department of Environmental Protection has recently passed a Stormwater Management Program. This has changed the review process for the SPDES Permit within New York City.

The applicant will now have to:

  1. Submit the SPDES permit application, a complete SWPPP (storm water pollution prevention plan) and any other information to the NYCDEP for review.
  2. Once the SWPPP is approved by the DEP, the applicant will have to submit the signed Acceptance Form to the DEC with a NYSDEC Notice of Intent (NOI).


For a SPDES Permit for construction activities, the following steps are needed in addition the steps mentioned above:

  1. The owner/developer will have to submit the Initiation form to the DEP with a maintenance easement (if applicable).
  2. The contractor will now have to submit the Permit Request form to the DEP for a Construction Permit. The DEP can do an inspection of the site while construction occurs.
  3. Once construction is over, the developer or owner will have to submit a NYSDEC Notice of Termination form (NOT) to the DEP to be signed and then submitted to the DEC.
  4. If post-construction stormwater management practices (SMPs) are required, the owner/developer will have to submit a Stormwater Maintenance Permit to the DEP and if issued, the owner will have to submit annual certification and 5-year permit renewal to the DEP. The DEP may inspect post-construction SMPs.


Do you need to apply for a SPDES Permit? Contact one of Walden’s environmental experts to discuss, at 516-624-7200 (Long Island), (518) 698-3012 (Capitol District) or (845) 253-8025 (Hudson Valley).