Public water system · NH2055020
ActiveMerrimack Valley Montessor Sch
At a glance
Merrimack Valley Montessor Sch (PWSID NH2055020) is an active non-transient non-community water system in Rockingham County, New Hampshire. It reports serving 60 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in November 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
60
Service connections
1
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Merrimack Valley Montessor Sch compare with other water systems in Rockingham County?
By EPA's size categories, Merrimack Valley Montessor Sch is a very small system (500 people or fewer). Rockingham County has 554 active public water systems. Its population served is well below the county average of 492 people per system, and accounts for less than 0.1% of the 272,726 people reported by systems filed under the county. Across New Hampshire, the 2,450 active systems average 508 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Merrimack Valley Montessor Sch is well below that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. New Hampshire has 453 active non-transient non-community water systems, 18% 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 Merrimack Valley Montessor Sch?
EPA lists Merrimack Valley Montessor Sch 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. 477 of the 554 active systems in Rockingham County (86%) are also privately owned.
Does Merrimack Valley Montessor Sch have drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in November 2024. The violations listed here began between October 1992 and November 2024. By type: 5 contaminant level above the legal limit, 3 monitoring and reporting, 2 public notice, recordkeeping or other, 1 reporting and 1 monitoring. The contaminant or rule involved most often is Total coliform bacteria (TCR) (8 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 |
|---|---|---|---|---|
| 2024-11-13 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-10-01 | MonitoringMonitoring, Additional Routine (RTCR) · code 3B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2014-12-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2013-11-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2013-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2008-12-01 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2008-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2008-09-21 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2008-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2000-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1995-01-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1992-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | 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.
Merrimack Valley Montessor Sch: frequently asked questions
Who runs Merrimack Valley Montessor Sch?
Merrimack Valley Montessor Sch (PWSID NH2055020) is a non-transient non-community water system privately owned. It is regulated by the NH state drinking water program.
How many people does Merrimack Valley Montessor Sch serve?
Merrimack Valley Montessor Sch reports serving 60 people through 1 service connection in Rockingham County, New Hampshire.
Where does Merrimack Valley Montessor Sch 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 Merrimack Valley Montessor Sch have any drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in November 2024. 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 Merrimack Valley Montessor Sch'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, 5 are health-based, and the most recent began in November 2024. For current results, consult EPA ECHO, or the NH state drinking water program.
Where can I find Merrimack Valley Montessor Sch's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Merrimack Valley Montessor Sch is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Rockingham County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Aquarion Water/Nh | Rockingham | 34,000 | Community | Groundwater |
| Portsmouth Water Works | Rockingham | 33,000 | Community | Surface water |
| Salem Water Dept | Rockingham | 21,000 | Community | Surface water |
| Derry Water Dept | Rockingham | 17,370 | Community | Purchased surface water |
| Seabrook Water Dept | Rockingham | 14,000 | Community | Groundwater |
| Exeter Water Dept | Rockingham | 12,236 | 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, “Merrimack Valley Montessor Sch, PWSID NH2055020, New Hampshire”, https://aquacensus.com/water-systems/new-hampshire/merrimack-valley-montessor-sch-nh2055020 (data as of October 1, 2026).