Water Distribution
On Long Island, every drop of drinking water comes from underground aquifers, a vital natural resource that requires careful management and protection. The distribution of this water is handled by a mix of public authorities, municipal districts, and local utilities, each responsible for delivering safe, clean water to homes and businesses. Below is a breakdown of how water service is organized across Nassau and Suffolk Counties.
Suffolk County Water Authority (SCWA)
The Suffolk County Water Authority (SCWA) is the largest water supplier on Long Island, serving more than 1.2 million residents across Suffolk County. Operating as a public-benefit corporation, SCWA is a not-for-profit utility – all revenue goes back into maintaining infrastructure, improving water quality, and protecting Suffolk’s aquifers.
SCWA is one of the largest groundwater suppliers in the United States and is widely recognized for its advanced treatment systems and extensive well network.
Water Authority of Western Nassau County (WAWNC)
In Nassau County, the Water Authority of Western Nassau County (WAWNC) provides water service to approximately 120,000 customers in western Nassau. This public utility manages wells, treatment facilities, and distribution pipelines, ensuring reliable service for households and businesses throughout its coverage area.
Water Authority of the North Shore (WANS)
On Nassau’s North Shore, communities have been transitioning water service from private providers to public ownership. The newly established Water Authority of the North Shore (WANS) was created to take over systems previously run by private companies, ensuring more accountability and long-term investment in local water infrastructure.
This authority serves communities including Glen Head, Sea Cliff, Roslyn Harbor, and surrounding areas, and reflects a growing trend of municipalities moving water systems into public control.
Local Water Districts in Nassau County
Beyond the large authorities, Nassau County also has numerous local water districts, each responsible for specific neighborhoods or villages. These districts often interconnect with each other to handle emergencies and share resources.
Some of the major districts include:
- Manhasset–Lakeville Water District – Serving Manhasset, Lake Success, and parts of Flower Hill and Plandome Heights.
- Port Washington Water District – Covering Port Washington, Baxter Estates, Manorhaven, and nearby communities.
- Roslyn Water District – Serving Roslyn, Roslyn Estates, and parts of East Hills, Flower Hill, and Port Washington.
- Garden City Park Water District – Longstanding provider serving Garden City Park, parts of Mineola, and surrounding areas.
- Jericho Water District – One of Nassau’s larger districts, serving Jericho, Syosset, Brookville, Muttontown, and parts of Oyster Bay.
- Hicksville Water District – Serving Hicksville and parts of Levittown, Plainview, and East Meadow.
These districts provide residents with local points of contact for billing, water quality information, and community conservation programs. Some Nassau communities were historically served by private water utilities, such as New York American Water, now owned by Liberty Utilities. These areas are gradually moving toward public ownership under authorities like the Water Authority of the North Shore.
With over 50 independent water districts, Nassau County’s water supply landscape is among the most fragmented in New York State.
Town & Village‑run Districts in Suffolk County
While the Suffolk County Water Authority supplies the majority of homes and businesses, several towns and villages operate their own independent water districts. These districts manage wells, treatment facilities, and distribution lines specifically for their communities, offering residents a local point of contact for billing, water quality updates, and service needs.
Notable Suffolk water districts include:
- Riverhead Water District – Serving Riverhead and surrounding hamlets, including residential, business, and agricultural customers.
- South Huntington Water District – Covering parts of Huntington, including South Huntington and Melville.
- Greenlawn Water District – Serving Greenlawn and sections of Huntington Township.
- Southampton Water District – Providing service to Southampton Village and nearby areas.
Although smaller in size compared to SCWA, these districts are vital to their communities and work to protect the Island’s aquifers while delivering reliable drinking water.
Oversight and Regulation
Water distribution on Long Island is closely regulated to ensure safety and reliability.
- In Suffolk County, the Department of Health Services oversees compliance with drinking water standards and monitors community systems.
- In Nassau County, the New York State Department of Public Service regulates private water companies, though most of the Island’s water is supplied by public authorities or districts.
| Region | Primary Providers | Example Local Districts |
|---|---|---|
| Suffolk County | SCWA + several town-run districts | Riverhead, South Huntington, Greenlawn, Southampton |
| Nassau County | WAWNC, Water Authority of North Shore, many small districts | Manhasset–Lakeville, Jericho, Hicksville, Garden City Park |
Why It Matters
Understanding who supplies your water is important for knowing where to go for billing questions, conservation initiatives, or emergency updates. Since all of Long Island’s drinking water comes from aquifers, residents also play a role in protecting this shared resource by supporting conservation efforts and staying informed about their local provider.
