County · New York

Nassau County, New York: drinking water records

Name: Drinking water records for Nassau County, New York
Creator: U.S. Environmental Protection Agency
License: https://www.usa.gov/government-works

Explore EPA records for 40 community water systems across 69 ZIP codes in Nassau County, then find water-testing resources and available recent monitoring-station readings.

In focus40Community water systems

Public records. Clearer context.

Data as of EPA UCMR 5 final release, August 2026 (file dated Aug 28, 2026) · EPA SDWIS 2026Q2 (file dated Jul 9, 2026). How we build these pages

Drinking-water records

EPA survey and compliance records are historical reports. UCMR 5 results are available for 33 of the 40 listed systems in this snapshot. A system with no reported PFAS detection is not a test of every tap or every contaminant.

systems in EPA's PFAS survey

systems where PFAS was found

systems at or above the PFOA or PFOS limit, on the yearly-average basis EPA uses

systems that have reached the lead action level

systems with a health-based violation since 2016

System population figures are summed from EPA registry records and can overlap where wholesalers and retail systems serve the same people. They are not a Census county-population estimate.

Water systems in this county

All 40 active community systems in the available county records, sorted by record completeness. Scroll the table to explore more systems.

Water system	People served	PFAS survey results	PFAS found	Health-based violations	Lead, 9 in 10 homes at or below
Liberty Utilities New York - Lynbrook NY2902835	220,000	1,050	3	3	4.2 ppbbelow the action level
Liberty Utilities New York - Merrick NY2902840	135,000	357	0	3	0 ppbbelow the action level
Jericho WD NY2902831	58,000	975	5	1	0 ppbbelow the action level
Long Beach City NY2902834	35,000	60	0	1	1.1 ppbbelow the action level
Plainview WD NY2902845	34,000	300	1	2	0 ppbbelow the action level
Wa of Western Nassau NY2902830	120,000	780	8	0	1.4 ppbbelow the action level
Town of Hempstead Water Department NY2900000	110,000	780	1	0	1 ppbbelow the action level
Hempstead (V) NY2902827	56,000	120	1	0	0 ppbbelow the action level
Hicksville WD NY2902829	48,000	480	1	0	1 ppbbelow the action level
Freeport (V) NY2902823	45,000	180	0	0	1.3 ppbbelow the action level
South Farmingdale WD NY2902854	44,700	416	0	0	1 ppbbelow the action level
Manhasset Lakeville WD NY2902836	43,000	570	5	0	1.6 ppbbelow the action level
Massapequa WD NY2902837	43,000	540	0	0	0 ppbbelow the action level
Port Washington WD NY2912267	34,000	540	6	0	2 ppbbelow the action level
Bethpage WD NY2902817	33,000	300	4	0	0 ppbbelow the action level
West Hempstead WD NY2902857	32,031	120	0	0	1.1 ppbbelow the action level
Glen Cove City NY2902826	28,000	240	2	0	3.9 ppbbelow the action level
Rockville Centre (V) NY2902848	24,700	240	0	0	1 ppbbelow the action level
Garden City (V) NY2902824	23,272	360	3	0	9.3 ppbbelow the action level
Mineola (V) NY2902839	20,600	240	4	0	2.2 ppbbelow the action level
Westbury WD NY2902856	20,500	540	3	0	0 ppbbelow the action level
Franklin Square WD NY2902822	20,000	180	0	0	0 ppbbelow the action level
Garden City Park WD NY2902825	18,000	300	3	0	2.6 ppbbelow the action level
Roslyn WD NY2902851	17,000	480	2	0	0 ppbbelow the action level
Albertson WD NY2902815	13,500	240	7	0	0 ppbbelow the action level
Liberty Utilities New York - Sea Cliff NY2902853	13,400	120	0	0	0 ppbbelow the action level
Carle Place WD NY2902818	9,005	150	0	0	1 ppbbelow the action level
Farmingdale (V) NY2902821	8,744	120	0	0	2.1 ppbbelow the action level
Oyster Bay WD NY2902844	8,700	120	3	0	5.7 ppbbelow the action level
Locust Valley WD NY2902833	7,500	300	2	0	0 ppbbelow the action level
Williston Park (V) NY2902858	7,287	120	5	0	2 ppbbelow the action level
Bayville (V) NY2902816	6,700	180	0	0	1.9 ppbbelow the action level
Old Westbury (V) NY2902843	4,700	60	0	0	5.4 ppbbelow the action level
Sands Point (V) NY2902852	2,900	0	0	0	2.1 ppbbelow the action level
East Williston (V) NY2902820	2,556	0	0	0	0 ppbbelow the action level
Lido-Point Lookout WD NY2902828	2,000	0	0	0	1.4 ppbbelow the action level
Plandome (V) NY2902846	1,600	0	0	0	0 ppbbelow the action level
Cathedral Gardens WD NY2902859	1,500	0	0	0	1.3 ppbbelow the action level
Glenwood WD NY2902850	1,000	0	0	0	1.3 ppbbelow the action level
Liberty Utilities New York - Mill Neck NY2902838	280	0	0	0	4.2 ppbbelow the action level

USGS · Monitoring stations

The water, more recently.

Available station readings in Nassau County, New York. Each measurement keeps its time, unit and original source.

These readings describe water at a monitoring station. They do not test your tap, measure PFAS or lead, or determine whether water is safe to drink or swim in.

Recent observations load when this section comes into view.

How these readings update

We check for updates every 10 minutes while this section is visible and show supported observations from the last 48 hours. The time beside a reading is when USGS measured it; the checked time is when our service retrieved the response. We mark a reading more than 6 hours old as older. Provisional observations can change after USGS review. A missing reading does not mean zero or clean water.

Temperature, pH, dissolved oxygen, turbidity, conductivity, streamflow and water level are shown only where a station reports them. Different measurements have different units and sampling intervals. USGS data and documentation.

Your next step

Water testing, reports & local help.

Use these official directories to find your drinking-water agency, a certified laboratory and public water records. We have not yet added an individually reviewed local resource list for this county.

Official national directories

Water testing

Find your state’s private-well program

EPA’s state directory points well owners to local program information. Services and eligibility vary by state and county.

U.S. Environmental Protection Agency
Source reviewed 2026-09-15 · Source updated 2026-08-05

Water testing

Find a certified drinking-water laboratory

Use EPA’s directory to reach your state’s laboratory certification program. EPA does not provide on-request testing of residential drinking water.

U.S. Environmental Protection Agency
Source reviewed 2026-09-15 · Source updated 2026-08-11

Public records

Find your utility’s Consumer Confidence Report

EPA links to community water-system reports and explains how to read them. Look for your actual supplier rather than assuming every address in a county shares one system.

U.S. Environmental Protection Agency
Source reviewed 2026-09-15 · Source updated 2026-09-09

Public records

Explore USGS water observations

Find current and historical observations from USGS monitoring locations, including available stream, lake, and groundwater data. Measurements vary by station and do not replace a test of your household water.

U.S. Geological Survey
Source reviewed 2026-09-15

A county overview cannot identify every property’s water provider. If you use a public water system, confirm its name on your bill and request its annual Consumer Confidence Report. Private wells need their own testing; public-system records do not describe a private well.

Understand water testing and laboratory reports

Resource descriptions are compiled by Tap Water Lookup. Review dates describe our source check, not a new water sample. How we review sources · Suggest a correction

Explore your area

Local coverage in Nassau County

69ZIP areas in this overview

Explore the water-system records, recent station readings and testing resources on this county page. They describe the systems and stations identified in each section; they are not a separate water test for every community.

Towns and communities

Albertson
Atlantic Beach
Baldwin
Barnum Island
Bayville
Bellmore
Bethpage
Brookville
Carle Place
Cedarhurst
East Hills
East Meadow
East Rockaway
Elmont
Floral Park
Franklin Square
Freeport
Garden City
Glen Cove
Glenwood Landing
Great Neck
Great Neck Estates
Hempstead
Hewlett Harbor
Hicksville
Inwood
Jericho
Kings Point
Lake Success
Lattingtown
Lawrence
Levittown
Long Beach
Lynbrook
Malverne
Manhasset
Massapequa
Massapequa Park
Merrick
Mill Neck
Mineola
Muttontown
North New Hyde Park
Oceanside
Old Bethpage
Old Brookville
Old Westbury
Oyster Bay Cove
Plainview
Point Lookout
Rockville Centre
Roosevelt
Roslyn Heights
Sands Point
Sea Cliff
Seaford
Syosset
Uniondale
Valley Stream
Wantagh
West Hempstead
Westbury
Williston Park
Woodbury
Woodmere

Explore water-system records Find water-testing resources

View ZIP areas and understand coverage

11001Floral Park
11003Elmont
11010Franklin Square
11020Lake Success
11021Great Neck Estates
11023Great Neck
11024Kings Point
11030Manhasset
11040North New Hyde Park
11042Lake Success
11050Sands Point
11096Inwood
11501Mineola
11507Albertson
11509Atlantic Beach
11510Baldwin
11514Carle Place
11516Cedarhurst
11518East Rockaway
11520Freeport
11530Garden City
11542Glen Cove
11545Old Brookville
11547Glenwood Landing
11548Brookville
11549Uniondale
11550Hempstead
11552West Hempstead
11553Uniondale
11554East Meadow
11556Uniondale
11557Hewlett Harbor
11558Barnum Island
11559Lawrence
11560Lattingtown
11561Long Beach
11563Lynbrook
11565Malverne
11566Merrick
11568Old Westbury
11569Point Lookout
11570Rockville Centre
11572Oceanside
11575Roosevelt
11576East Hills
11577Roslyn Heights
11579Sea Cliff
11580Valley Stream
11581Valley Stream
11590Westbury
11596Williston Park
11598Woodmere
11709Bayville
11710Bellmore
11714Bethpage
11732Muttontown
11753Jericho
11756Levittown
11758Massapequa
11762Massapequa Park
11765Mill Neck
11771Oyster Bay Cove
11783Seaford
11791Syosset
11793Wantagh
11797Woodbury
11801Hicksville
11803Plainview
11804Old Bethpage

These Census ZIP Code Tabulation Areas are grouped here by their largest county overlap. A ZIP area can cross county lines and contain several water suppliers or private wells. Place labels reflect Census geography, not verified postal city names or utility service boundaries.

Records for these areas are currently presented in this county overview rather than individual ZIP reports. An unpublished report does not mean there are no water records. Confirm your supplier on your water bill; if you use a private well, testing your own well is the relevant next step.

Beyond this county page

Keep reading. Compare nearby.

PFASChoosing a PFAS filterPFAS was found in 20 of the 33 systems EPA surveyed here. See how to check a filter’s certified PFAS reduction.LeadChoosing a lead filter5 systems here have reached the lead action level. See how to check a filter’s lead-reduction certification.Your utilityFind your annual water reportConfirm the supplier on your bill, then read its Consumer Confidence Report for local results.

Counties near Nassau County

All New York counties

Sources and scope

EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Database prepared 2026-09-03.

Counts cover the systems that report this county to EPA. A water system may cross county lines. "Found" means at least one result at or above the laboratory reporting level; it is not a compliance finding.

Compiled by Tap Water Lookup from the sources identified on this page. Read the methodology and review process.