Nassau County’s Storm Water Management

Nassau County’s Storm Water Management


In an effort to preserve Long Island's coastal heritage and natural resources, Nassau County has taken the initiative to create an inter-municipal Nassau County Storm Water Management Program (NCSWMP). This program will depend on the participation of every municipality in the county to work with the New York State Department of Environmental Conservation (NYSDEC) to manage our storm water and reduce the toxic runoff that affects our lakes, streams, and coastal waterways.

Roughly 40% of our nation's surface waters do not meet water quality standards, and are contaminated by pathogens, excess nutrients, and chemical pollutants. The health of these surface waters is vital to human health, wildlife, and to our regional economies. Yet every day, storm water runs into these important bodies of water after being contaminated by surface wastes, chemicals, and excess sediment.

Storm water discharges directly into our open waters or to our groundwater system [our aquifers]. Unlike water, which is used in many of our homes, storm water is not collected in a sewer system and passed through a water treatment plant before being discharged. Instead, it is collected in almost 1,000 groundwater recharge basins or directed to the south shore bays or Long Island Sound through 3,720 storm water outfalls or almost 60 miles of open stream corridors.

This means that contaminants that are picked up by storm water after falling on our county's roads, parks, homes, and parking lots flow directly into the groundwater system that we use for our drinking water, or into the sensitive open waters surrounding our island. These pollutants include nutrients, silt/ sediment, pathogens, oil and grease, metals, debris, and litter. The NYSDEC and Nassau County are working together to reduce six pollutants of concern:

  • Nitrogen
  • Oxygen Demand
  • Pathogens
  • Phosphorus
  • Polychlorinated Biphenyls
  • Silt and Sediment

The NCSWMP is a comprehensive program to reduce the levels of contaminants in Nassau County's storm water runoff and educate the public about their impacts on storm water. Storm water systems are the responsibility of the County and its 67 Towns, Villages, and Cities. As the largest municipality, Nassau County has taken the lead in coordinating the NCSWMP and acting as a clearinghouse of information for concerned parties. The Nassau County Department of Public Works Water Engineering Unit is in charge of implementing the plan, including water testing, education, and pollution prevention measures. The five elements of the NCSWMP are:

  • Public Education
  • Public Involvement
  • Illicit Discharge Detection and Elimination
  • Construction Site Storm Water Runoff Control and Post-Construction Storm Water Management
  • Pollution Prevention and Good Housekeeping for Municipal Operations
League to which this content belongs: 
Nassau County Inter-League Organization