The New York State Department of Environmental Conservation (“DEC”) has issued public notice of a draft State Pollutant Discharge Elimination System (“SPDES”) permit for Stormwater Discharges from Municipal Separate Storm Sewer Systems (“MS4s”) owned or operated by the City of New York (the “draft MS4 permit”).  Under existing law, DEC regulates discharges from MS4s that are located within the boundaries of a Census Bureau defined “urbanized area” or “additionally designated areas.”  DEC authorizes most MS4s to be covered under a SPDES General Permit; however, New York City MS4s are regulated through a separate general permit.  The draft MS4 permit would consolidate the MS4 sections from 10 of the 14 existing SPDES Permits that govern each of the Waste Water Treatment Plants operated by the New York City Department of Environmental Protection.

The MS4 permit would authorize stormwater discharges from large MS4s currently existing within the jurisdictional boundaries of the City of New York and limited to those MS4 outfalls owned or operated by New York City.  The following areas would be regulated under the permit: City-owned storm sewers that ultimately discharge to MS4 outfalls also owned by the City; High Level Storm Sewers and Bluebelts that ultimately discharge to MS4 outfalls owned by the City; SPDES general permitted construction and industrial stormwater facilities/areas that ultimately discharge to MS4 outfalls owned by the City; and New York City municipal operations and facilities that drain by overland flow to surface waters of New York State.   Under the draft MS4 permit, the City would be excluded from monitoring/administering construction and industrial stormwater facilities/areas operating pursuant to separate general permits, including 1) facilities and operations that drain directly into surface waters of New York State through pipes or open channel conveyances that are not owned or operated by the City, and 2) facilities and operations for which NYC is not responsible and that drain by overland flow to surface waters of New York State.

Pursuant to the MS4 permit, New York City would be required to develop a Stormwater Management Program Plan (“SWMP”) that describes how it would meet the requirements of the permit.  The draft MS$ permit would require the City to submit its SWMP within three years of the effective date of the permit.  The permit would require that the City develop, implement, and enforce public education and participation programs, an Illicit Discharge Detection & Elimination (“IDDE”) program, a Construction Site Stormwater Runoff Control program, a Post Construction Stormwater Management program, and a good housekeeping program for municipal operations – with each of these programs to be described in the SWMP.

The Construction Site Stormwater Runoff Control Program required under the draft MS4 permit would apply to construction activities that result in a land disturbance of greater than or equal to one acre – the same threshold for obtaining coverage under DEC’s General Permit for Construction Activities.  To meet this requirement, the City would need to adopt an ordinance or other regulatory mechanism requiring the implementation of proper erosion and sediment controls and controls for other wastes at applicable construction sites; develop written procedures for site plan review of construction plans that consider potential water quality impacts; develop written procedures for site inspection and enforcement of control measures; develop sanctions to ensure compliance; develop procedures for the receipt and consideration of complaints and other information submitted by the public; develop and maintain an inventory of active construction sites within their jurisdiction; and select and assess appropriate construction BMPs and measureable goals to ensure the reduction of pollutants of concern.  Additional information can be found in the draft MS4 permit Fact Sheet.

Comments to the draft MS4 permit must be submitted to DEC no later than March 7, 2014.