A variety of factors influence water quality in the ocean and bays surrounding Fire Island, and this affects the habitat for the plants and animals that live here (including us!). Clean, safe water for recreation is an important resource. Drinking water for the south shore of Long Island comes from sources deep within the aquifers beneath the surface of Fire Island.
As a typical East Coast barrier island-lagoon system, circulation of higher salinity water from the Atlantic Ocean-flushing regularly through inlets on each end of Fire Island-is commingled in the estuary with fresh water from mainland Long Island and to a lesser degree from Fire Island.
Salinity and water temperature primarily affect the biology of the waters around Fire Island, but nutrients and turbidity also affect where plants and animals can survive. The chemicals and organisms in the water can also affect human health and safety.
Other federal, New York State, and Suffolk County agencies conduct research and water quality monitoring programs within the boundaries of Fire Island National Seashore or adjacent waters.
The National Park Service (NPS) has created a protocol to monitor estuarine nutrient enrichment for its Vital Signs Monitoring Program of the .