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Long Island MS4 Phase II Planning Program

Stormwater and MS4s

Urban stormwater runoff is one of the top water quality issues in New York. When it rains, or when snow melts, some of the water soaks into the ground, while the rest collects pollutants as it flows across impervious surfaces such as streets, sidewalks, parking lots, driveways, exposed soil, and lawns before entering sewer systems and local waterbodies. In urban areas, stormwater usually flows through a network of drains, pipes and ditches called a Municipal Separate Storm Sewer System (MS4) before being discharged to nearby waterbodies, often without treatment.

map of regulated MS4s on Long Island
Most Long Island municipalities are operators of regulated MS4s
(shown in purple). See DEC's Stormwater Interactive Map for
a full-size version.

Many waterbodies on Long Island have water quality issues related to stormwater runoff. Reducing the amount of runoff is an important part of efforts to protect and improve water quality that is essential for fishing, tourism and recreation. In New York, operators of MS4s within urbanized areas (including most Long Island communities) must have permit authorization for stormwater discharges and must implement a Stormwater Management Program (SWMP) to help keep pollutants from entering the storm sewer system and flowing to a local waterbody.

Project Overview

In 2009, the Interstate Environmental Commission (IEC) received a $232,785 American Recovery and Reinvestment Act (ARRA) grant from DEC to support stormwater management planning in over 100 communities in Nassau and Suffolk Counties, focusing on MS4s that discharge to waterbodies impaired by pathogens (disease-causing bacteria or viruses). By assisting municipalities with planning, implementing, evaluating, and documenting their Stormwater Management Programs, this project helped Long Island communities meet New York State requirements to manage stormwater runoff, and help protect and restore Long Island's waterbodies.

Project Status

IEC completed this project in January, 2012. IEC worked in partnership with the New York Sea Grant (NYSG) Long Island MS4 Planning Program on this project. The goal was to support stormwater management planning by providing technical assistance, outreach, and training to municipal officials in MS4 communities and members of inter-municipal coalitions.

Long Island shore
Managing stormwater runoff helps
protect Long Island's waterbodies.

The Long Island MS4 Planning Program provided over 100 Long Island municipalities with technical assistance for planning, implementing, evaluating, and documenting their stormwater programs. Over 50 MS4 annual reports were reviewed, and written feedback was provided on each. In-depth consultations were conducted with 25 municipalities to promote their ability to evaluate the effectiveness of their SWMPs and to provide additional guidance and technical resources. The Long Island MS4 Planning Program staff also accompanied DEC and U.S. EPA on site visits of municipal MS4 facilities to review their stormwater programs.

In addition, a series of presentations and workgroup meetings were held for municipal officials, planners, stormwater program managers, highway department personnel, building and site inspectors, consultants, and other local representatives who make important land-use decisions. Topics of these outreach activities included: watershed-based pathogen control; New York State construction and post-construction design standards; green infrastructure; inter-municipal initiatives; and sustainable stormwater program funding mechanisms.

Since stormwater flows across municipal boundaries, it is more cost-effective and efficient to organize and coordinate local stormwater management efforts with larger regional watershed efforts. To strengthen relationships and improve coordination of current inter-municipal programs and practices, the NYSG Long Island MS4 Planning Program provided outreach and training to members of regional groups on Long Island such as the as the Long Island Sound Study, the Peconic Estuary Program, the South Shore Estuary Reserve Council, the Hempstead Harbor Protection Committee, the Manhasset Bay Protection Committee, and the recently formed Oyster Bay/Cold Spring Harbor Protection Committee.

Other outreach activities performed for this project included providing one-on-one stormwater planning assistance via telephone and email, and managing the Long Island MS4 Listserv, which is an e-mail discussion list for Long Island municipal officials and staff who are responsible for meeting MS4 requirements. The listserv provides a forum for subscribers to share expertise, access training and funding opportunities, and receive answers to their questions.

Final Progress Report

When each ARRA 604(b) project is complete, DEC requires a final report summarizing the entire project to be submitted. The report includes a description of the project's goals, work accomplished, and final project outcomes.

To view the final progress report for this project, click the following link:

Long Island MS4 Planning (NYSG LI-MS4 Planning) Program - Final Report (PDF) (180 KB)

About the IEC and New York Sea Grant

IEC is an interstate water and air pollution control agency serving New York, New Jersey and Connecticut. Originally formed in 1936 by the states of New York and New Jersey, Connecticut joined in 1941. In coordination with its member states and the U.S. EPA, IEC continues to enforce water and air quality regulations. IEC has expanded its scope of activities to advance water quality education efforts though promotion of public participation, outreach activities, and research initiatives.

New York Sea Grant is a cooperative program of the State University of New York and Cornell University that supports research and outreach projects that promote the wise use and protection of coastal areas of New York.

Contact Information

Interstate Environmental Commission

311 West 43rd Street, Suite 201, New York, NY 10036

New York Sea Grant

121 Discovery Hall, SUNY at Stony Brook, Stony Brook, NY 11794