Public water system · MA4197000
ActiveWannacomet Water Company
At a glance
Wannacomet Water Company (PWSID MA4197000) is an active community water system in Nantucket County, Massachusetts. It reports serving 27,703 people through 7,221 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
27,703
Service connections
7,221
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Wannacomet Water Company compare with other water systems in Nantucket County?
By EPA's size categories, Wannacomet Water Company is a large system (10,001 to 100,000 people). Nantucket County has 5 active public water systems, and Wannacomet Water Company is the largest of them by population served. Its population served is about 4.3 times the county average of 6,513 people per system, and accounts for 85% of the 32,563 people reported by systems filed under the county. Across Massachusetts, the 1,636 active systems average 6,275 people each. Nationally, the average active community water system reports serving 6,703 people, so Wannacomet Water Company is about 4.1 times 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. Massachusetts has 531 active community water systems, 32% of the state's 1,636 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,354 Massachusetts systems (83%) list groundwater as their primary source.
Who owns and regulates Wannacomet Water Company?
EPA lists Wannacomet Water Company as owned by a local government. The MA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 3 of the 5 active systems in Nantucket County (60%) are also owned by a local government.
Does Wannacomet Water Company have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2025. The violations listed here began between April 2025 and July 2025. By type: 11 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminants or rules involved are Consumer Confidence Rule, Lead and Copper Rule, Vinyl chloride and Antimony. EPA lists 10 as archived, 1 as unaddressed and 1 as addressed. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement. Addressed means the violation is not resolved or archived and is covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-07-02 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Unaddressed |
| 2025-06-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Addressed |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Vinyl chloridecode 2976 | No | Archived |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Antimonycode 1074 | No | Archived |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitritecode 1041 | No | Archived |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,1-Trichloroethanecode 2981 | No | Archived |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Cyanidecode 1024 | No | Archived |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Archived |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Cadmiumcode 1015 | No | Archived |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chromiumcode 1020 | No | Archived |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Benzenecode 2990 | No | Archived |
The 12 most recent 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.
Wannacomet Water Company: frequently asked questions
Who runs Wannacomet Water Company?
Wannacomet Water Company (PWSID MA4197000) is a community water system owned by a local government. It is regulated by the MA state drinking water program.
How many people does Wannacomet Water Company serve?
Wannacomet Water Company reports serving 27,703 people through 7,221 service connections in Nantucket County, Massachusetts.
Where does Wannacomet Water Company get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Wannacomet Water Company have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2025. 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 Wannacomet Water Company'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. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the MA state drinking water program.
Where can I find Wannacomet Water Company's water quality report?
As a community water system, Wannacomet Water Company 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 Nantucket County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Siasconset Water Department | Nantucket | 3,000 | Community | Groundwater |
| Surfside Beach | Nantucket | 1,500 | Transient non-community | Groundwater |
| Wauwinet House | Nantucket | 300 | Transient non-community | Groundwater |
| Sankaty Head Golf Club Inc.. | Nantucket | 60 | Transient non-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, “Wannacomet Water Company, PWSID MA4197000, Massachusetts”, https://aquacensus.com/water-systems/massachusetts/wannacomet-water-company-ma4197000 (data as of October 1, 2026).