Public water system · NY5105656
ActiveSmithtown Water District
At a glance
Smithtown Water District (PWSID NY5105656) is an active community water system in Suffolk County, New York. It reports serving 19,635 people through 5,610 service connections. Its primary water source is purchased groundwater, and EPA lists it as owned by a local government. EPA's records list 2 violations for this system; all are health-based, and the most recent began in July 2015.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
19,635
Service connections
5,610
Primary source
GWP
Purchased groundwater
System type
CWS
Community water system
System record
How does Smithtown Water District compare with other water systems in Suffolk County?
By EPA's size categories, Smithtown Water District is a large system (10,001 to 100,000 people). Suffolk County has 151 active public water systems, and Smithtown Water District is the 6th-largest of them by population served. Its population served is about twice the county average of 9,192 people per system, and accounts for 1.4% of the 1,387,972 people reported by systems filed under the county. Across New York, the 8,167 active systems average 2,374 people each. Nationally, the average active community water system reports serving 6,703 people, so Smithtown Water District is about 193% above that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. New York has 2,281 active community water systems, 28% of the state's 8,167 active systems. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own. 114 New York systems (1.4%) list purchased groundwater as their primary source.
Who owns and regulates Smithtown Water District?
EPA lists Smithtown Water District as owned by a local government. The NY state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 38 of the 151 active systems in Suffolk County (25%) are also owned by a local government.
Does Smithtown Water District have drinking water violations?
EPA's records list 2 violations for this system; all are health-based, and the most recent began in July 2015. The violations listed here began between June 2003 and July 2015. By type: 2 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (2 of them). EPA lists 2 as resolved. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2015-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2003-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
All 2 violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Smithtown Water District: frequently asked questions
Who runs Smithtown Water District?
Smithtown Water District (PWSID NY5105656) is a community water system owned by a local government. It is regulated by the NY state drinking water program.
How many people does Smithtown Water District serve?
Smithtown Water District reports serving 19,635 people through 5,610 service connections in Suffolk County, New York.
Where does Smithtown Water District get its water?
EPA SDWIS lists this system's primary water source as purchased groundwater. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own.
Does Smithtown Water District have any drinking water violations?
EPA's records list 2 violations for this system; all are health-based, and the most recent began in July 2015. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Smithtown Water District's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. EPA's records list 2 violations for this system; all are health-based, and the most recent began in July 2015. For current results, consult the system's annual water quality report, EPA ECHO, or the NY state drinking water program.
Where can I find Smithtown Water District's water quality report?
As a community water system, Smithtown Water District must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Suffolk County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Suffolk County Water Authority | Suffolk | 1,100,000 | Community | Groundwater |
| South Huntington Water District | Suffolk | 81,760 | Community | Groundwater |
| Greenlawn Water District | Suffolk | 42,000 | Community | Groundwater |
| Riverhead Water District | Suffolk | 35,000 | Community | Groundwater |
| Dix Hills Water District | Suffolk | 34,522 | Community | Groundwater |
| Hampton Bays Water District | Suffolk | 12,500 | Community | Groundwater |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Smithtown Water District, PWSID NY5105656, New York”, https://aquacensus.com/water-systems/new-york/smithtown-water-district-ny5105656 (data as of October 1, 2026).