New York City’s Municipal Separate Storm Sewer System (MS4) Stormwater Management Program is a multiagency effort led by the Department of Environmental Protection (DEP) to reduce pollution in stormwater runoff in the MS4 Area of NYC. This MS4 Map represents the known MS4 outfalls and drainage areas as of August 1, 2020 and provides additional data relevant to the MS4 Permit. The MS4 map only shows areas draining to the Municipal Separate Storm Sewer System. DEP also maintains combined sewer and sanitary sewer systems; these service area delineations are not represented on this map. More information about the MS4 Stormwater Management Program is available at www.nyc.gov/dep/ms4

This dataset contains the locations and detailed information of green infrastructure practices in NYC neighborhoods built primarily through NYC Green Infrastructure Program initiatives. Green infrastructure (GI) collects stormwater from streets, sidewalks, and other hard surfaces before it can enter the sewer system or cause local flooding. The GI practice data contained in this dataset includes the location, program area, status, and type of GI. This dataset is updated by the NYC Department of Environmental Protection on a monthly basis.

The “Porous_Permeable_Pavement” polygon layer contains constructed porous permeable pavement practices only, which fall under the ROW program area category. The three ROW Porous Permeable Pavement asset types in this shapefile are Porous Concrete, Permeable Pavement, and Porous Asphalt."

This layer is part of a larger Green Infrastructure dataset. You can download the full dataset and the data dictionary below under “Attachments”.

Source Data: DEP Green Infrastructure Program Map

The dataset represents the locations of combined sewer overflow (CSOs) outfall locations in NYS. Combined sewers collect stormwater runoff, domestic sewage and industrial wastewater in the same pipe and bring it to a wastewater treatment facility. They are designed to overflow during heavy rain events, causing excess water to be discharged directly into a waterbody. The public is advised to avoid contact while recreating within waterbodies with a CSO during or following rain or snowmelt. There are about 800 CSO outfalls in New York State. This is a decrease from about 1,300 in 1993, due to CSO abatements completed by the permittees.Service is updated annually and was last updated 11/4/2024.For more information or to download layer see https://www.dec.ny.gov/chemical/48595.html1. The NYS DEC asks to be credited in derived products. 2. Secondary Distribution of the data is not allowed. 3. Any documentation provided is an integral part of the data set. Failure to use the documentation in conjunction with the digital data constitutes misuse of the data. 4. Although every effort has been made to ensure the accuracy of information, errors may be reflected in the data supplied. The user must be aware of data conditions and bear responsibility for the appropriate use of the information with respect to possible errors, original map scale, collection methodology, currency of data, and other conditions.

NYC Green Infrastructure Program initiatives. Green infrastructure (GI) collects stormwater from streets, sidewalks, and other hard surfaces before it can enter the sewer system or cause local flooding. The GI practice data contained in this dataset includes the location, program area, status, and type of GI. Please visit nyc.gov/dep/gimap to view the DEP Green Infrastructure Map.