Public water system · NH0353020
ActiveMascoma Valley Coop
At a glance
Mascoma Valley Coop (PWSID NH0353020) is an active community water system in Grafton County, New Hampshire. It reports serving 73 people through 29 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
73
Service connections
29
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Mascoma Valley Coop compare with other water systems in Grafton County?
By EPA's size categories, Mascoma Valley Coop is a very small system (500 people or fewer). Grafton County has 270 active public water systems. Its population served is well below the county average of 394 people per system, and accounts for less than 0.1% of the 106,236 people reported by systems filed under the county. Across New Hampshire, the 2,450 active systems average 508 people each. Nationally, the average active community water system reports serving 6,703 people, so Mascoma Valley Coop is well below 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 Hampshire has 706 active community water systems, 29% of the state's 2,450 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,374 New Hampshire systems (97%) list groundwater as their primary source.
Who owns and regulates Mascoma Valley Coop?
EPA lists Mascoma Valley Coop as privately owned. The NH state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 213 of the 270 active systems in Grafton County (79%) are also privately owned.
Does Mascoma Valley Coop have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in January 2026. The violations listed here began between October 1998 and January 2026. By type: 9 monitoring and reporting, 2 public notice, recordkeeping or other and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 of them). EPA lists 12 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 |
|---|---|---|---|---|
| 2026-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2008-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2006-02-06 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2005-11-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2001-08-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1999-05-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1998-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Carbon tetrachloridecode 2982 | No | Resolved |
| 1998-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Vinyl chloridecode 2976 | No | Resolved |
| 1998-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | cis-1,2-Dichloroethylenecode 2380 | No | Resolved |
| 1998-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 1998-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 1998-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Styrenecode 2996 | No | Resolved |
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.
Mascoma Valley Coop: frequently asked questions
Who runs Mascoma Valley Coop?
Mascoma Valley Coop (PWSID NH0353020) is a community water system privately owned. It is regulated by the NH state drinking water program.
How many people does Mascoma Valley Coop serve?
Mascoma Valley Coop reports serving 73 people through 29 service connections in Grafton County, New Hampshire.
Where does Mascoma Valley Coop 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 Mascoma Valley Coop have any drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in January 2026. 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 Mascoma Valley Coop'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, one is health-based, and the most recent began in January 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the NH state drinking water program.
Where can I find Mascoma Valley Coop's water quality report?
As a community water system, Mascoma Valley Coop 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 Grafton County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Lebanon Water Dept | Grafton | 13,600 | Community | Surface water |
| Hanover Water Dept | Grafton | 9,600 | Community | Surface water |
| Plymouth Vlg Water and Sewer | Grafton | 6,700 | Community | Groundwater |
| Littleton Water and Light | Grafton | 6,500 | Community | Surface water |
| Bristol Water Works | Grafton | 3,575 | Community | Groundwater |
| Lincoln Water Works | Grafton | 3,300 | Community | Surface water |
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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, “Mascoma Valley Coop, PWSID NH0353020, New Hampshire”, https://aquacensus.com/water-systems/new-hampshire/mascoma-valley-coop-nh0353020 (data as of October 1, 2026).