Public water system · NH0773020
ActiveColby Brook Estates
At a glance
Colby Brook Estates (PWSID NH0773020) is an active community water system in Merrimack County, New Hampshire. It reports serving 68 people through 27 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, 6 are health-based, and the most recent began in June 2014.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
68
Service connections
27
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Colby Brook Estates compare with other water systems in Merrimack County?
By EPA's size categories, Colby Brook Estates is a very small system (500 people or fewer). Merrimack County has 244 active public water systems. Its population served is well below the county average of 509 people per system, and accounts for less than 0.1% of the 124,152 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 Colby Brook Estates 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 Colby Brook Estates?
EPA lists Colby Brook Estates 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. 194 of the 244 active systems in Merrimack County (80%) are also privately owned.
Does Colby Brook Estates have drinking water violations?
Of the 12 most recent violations in EPA's records, 6 are health-based, and the most recent began in June 2014. The violations listed here began between October 1999 and June 2014. By type: 6 contaminant level above the legal limit, 4 monitoring and reporting and 2 public notice, recordkeeping or other. The contaminant or rule involved most often is Arsenic (7 of them). EPA lists 11 as resolved and 1 as archived. 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. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2014-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2013-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2013-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2013-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2013-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2012-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2012-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2006-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2002-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 1999-10-19 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 1999-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | 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.
Colby Brook Estates: frequently asked questions
Who runs Colby Brook Estates?
Colby Brook Estates (PWSID NH0773020) is a community water system privately owned. It is regulated by the NH state drinking water program.
How many people does Colby Brook Estates serve?
Colby Brook Estates reports serving 68 people through 27 service connections in Merrimack County, New Hampshire.
Where does Colby Brook Estates 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 Colby Brook Estates have any drinking water violations?
Of the 12 most recent violations in EPA's records, 6 are health-based, and the most recent began in June 2014. 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 Colby Brook Estates' 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, 6 are health-based, and the most recent began in June 2014. For current results, consult the system's annual water quality report, EPA ECHO, or the NH state drinking water program.
Where can I find Colby Brook Estates' water quality report?
As a community water system, Colby Brook Estates 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 Merrimack County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Concord Water Dept | Merrimack | 44,215 | Community | Surface water |
| Franklin Water Works | Merrimack | 7,200 | Community | Groundwater |
| Pembroke Water Works | Merrimack | 5,200 | Community | Groundwater |
| Central Hooksett Water Pct | Merrimack | 4,650 | Community | Purchased surface water |
| Penacook Boscawen Water Pct | Merrimack | 3,800 | Community | Groundwater |
| New London Springfield Water | Merrimack | 3,250 | 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, “Colby Brook Estates, PWSID NH0773020, New Hampshire”, https://aquacensus.com/water-systems/new-hampshire/colby-brook-estates-nh0773020 (data as of October 1, 2026).