East Williston (V)

What EPA’s and New York’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves: 2,556 people
Connections: 874
Water source: Groundwater bought from another system
Based in: East Williston (V), NY
County: Nassau
Owner: Local government

The ZIP code it serves

11596

The short answer

Nothing in EPA’s and New York’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.

What was found

Total trihalomethanes (TTHM) and haloacetic acids (HAA5): New York’s yearly summaries per water system, 2020 to 2024.

Below EPA’s limits1

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

0.66ppb

Highest yearly average, 2020 to 2024

2024: not found

Averaged by year, the highest was 0.66 ppb, in 2023, below EPA’s legal limit of 80 ppb. In 2024, the latest year on file, it wasn’t found.

What handles it

NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

2 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.

Haloacetic acids (HAA5)
Lead

Violations since 2016

No health-based violations on file with EPA since 2016.

What this report can’t tell you

Everything else. Total trihalomethanes (TTHM) and haloacetic acids (HAA5) results here are New York’s own yearly summaries from 2020 on, with EPA’s national file for 2012 to 2019. East Williston (V)’s own annual report, which it must send you every year, has the contaminants this page does not show.
Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.
What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.
Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; New York’s yearly summaries cover 2020 to 2024.

Testing your own tap

East Williston (V)’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab New York certifies.

The 3 labs New York certifies closest to the area East Williston (V) serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

EMSL Analytical, Inc.
Carle Place, NY · about 2 miles
Certified for bacteria, lead and copper, asbestos
(516) 997-7251
Nassau County Dept of Health
Hempstead, NY · about 4 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics
(516) 572-1202
NY Environmental and Analytical Labs Inc.
Port Washington, NY · about 6 miles
Certified for bacteria, lead and copper
(516) 944-9500

All 161 certified labs for New York

Sources

EPA UCMR 5 occurrence data, file of Oct. 15, 2026
EPA SDWA bulk download (SDWIS federal data), 2026 Q3
New York State Department of Health, Environmental Public Health Tracker, results from Jan. 1, 2020 to Dec. 31, 2024, read Oct. 8, 2026
Certified labs: NYS Environmental Laboratory Approval Program (ELAP), drinking water labs, as listed in TNI LAMS, read Oct. 11, 2026; distances from the Census 2020 ZIP code tabulation area gazetteer
Limits and goals: each contaminant’s page, with its EPA source.
How this page is built: methodology.