Information Sheet for Consumers Served by Long Island Public Water Systems

February 2002

Source Water Assessment Program

The 1996 Amendments to the Safe Drinking Water Act place a strong emphasis on the protection of surface and ground water sources used for public drinking water. As a result, each state must develop a Source Water Assessment Program, and complete assessments of the sources of water used by public drinking water systems by May 2003.

The New York State Department of Health (NYS DOH) is responsible for developing New York's Source Water Assessment Program and ensuring that the assessments are completed for all the public water systems. In developing the Source Water Assessment Plan, the New York State Department of Health gathered extensive input from many public and private interests. New York's Source Water Assessment Plan was approved by the United States Environmental Protection Agency (US EPA) in November 1999.

New York's Source Water Assessment Program on Long Island

Long Island relies on ground water as a source of drinking water and the ground water system is classified as a sole-source aquifer. In Nassau and Suffolk Counties, there are over 500 public water systems that rely on more than 1,500 different ground water source wells.

The regional aquifer systems on Long Island have been extensively investigated and assessed. Extensive ground water resource management and protection efforts have evolved related to Long Island's unique regional setting and hydrogeological characteristics.

The New York State Department of Health worked with the Nassau and Suffolk County Health Departments and other interested parties to develop a specific approach appropriate for Long Island. Because of the technical nature of the approach, the New York State Department of Health has hired a contractor (Camp, Dresser and McKee) to complete source water assessments for public water systems in Nassau and Suffolk counties.

Contractor Activities

The contractor is responsible for specific tasks associated with conducting source water assessments on Long Island. These tasks are detailed below.

  1. Review and Assemble Existing Information

    The contractor will review and compile the key aspects of historical and ongoing ground water management programs and studies for Long Island drinking water. The contractor will also look at emerging issues about contaminants and review all the relevant data available for each public water supply well. This information has been compiled by the local and State Departments of Health.

    The contractor will review land use data and information about specific contaminant sources, such as landfills and Superfund sites, that are located within a well's recharge area. Much of the information about land use and contaminant sources is available in the digital format known as Geographic Information Systems (GIS).

  2. Delineate Source Water Assessment and Well Recharge Areas

    For many parts of the Long Island regional aquifer system, three-dimensional computer models have already been developed. The contractor will build upon the information in these existing models and incorporate new data and information to better predict ground water flow within the entire aquifer system and to each public water supply well. Also, the contractor will map the estimated ground water recharge area for each public water supply well. The information generated in this step will provide additional detail about the origins of the source water to each well and the likelihood of contaminants to affect a particular public water supply well.

  3. Inventory Contaminant Sources

    The contractor will review the land uses and specific facilities, such as landfills and Superfund sites, within the well's recharge area to assess their potential to contaminate the ground water.

  4. Evaluate Susceptibility to Contamination

    The assessments will not only look at sources of contamination within the ground water recharge area for a well, but also how likely contamination will reach that well. The contractor will consider both of these factors to determine the overall susceptibility of the well to contamination.

  5. Provide Assessment Information to the Public

    The contractor will prepare draft source water assessments for each well or well field. Before the Long Island Source Water Assessments are finalized, the New York State Department of Health will hold three public meetings at different locations on Long Island. These meetings will provide an opportunity for interested parties to comment on how this information can be best communicated to the public and utilized for management and protection of Long Island's ground water resources.

    After the draft reports have been reviewed, the NYS DOH will finalize summary reports of the assessments. The state and local health departments will distribute these final source water assessment reports to government offices, libraries, interested parties and other appropriate locations.

Questions about New York's Source Water Assessment Program?

Please contact:

Center for Environmental Health
Bureau of Water Supply Protection
Empire State Plaza-Corning Tower, Room 1110
Albany, New York 12237