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Community Water System · PWS NH1781010

Groveton Water Sys

Northumberland, New Hampshire 03582 - drinking water served from groundwater sources to 2,650 people, tracked in EPA SDWIS and UCMR5.

2,650
People served
79
EPA violations
11
Health-based
Untested
UCMR5 result

The verdict

EPA records 79 drinking-water violations at Groveton Water Sys, 14% of them health-based - above the New Hampshire per-system average.

79
Total EPA violations on record
14%
Health-based (MCL / treatment failure)
2,650
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Groveton Water Sys

Groveton Water Sys is a local-owned community water system that delivers drinking water to 2,650 residents in Northumberland, New Hampshire (Coos County) through 765 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 79 total violations for this system , of which 11 (14%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 57 monitoring and reporting violations are on file. The most recent violation on record dates to 2008.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 10 violations (MCL, health-based). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across New Hampshire, EPA tracks 2,453 public water systems serving 1,242,123 people, with 155,970 cumulative violations and 29,649 health-based violations on record. About 90% of systems in the state carry at least one violation, and state-wide the average per system is 63.6 violations. Statewide, 23 of 51 UCMR5-tested systems have reported PFAS detections (45.1%).

Groveton Water Sys's 79 violations sit above the New Hampshire average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
2,650
Total Violations
79
Health-Based Violations
11
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
765
County
Coos
School/Daycare
No
MCL Violations
10
Monitoring Violations
57
Treatment Tech Violations
1

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MCL 10 1991
Nitrate MR 8 1994
Consumer Confidence Rule Other 6 2008
Coliform (TCR) MR 4 1991
Chlorine MR 3 2006
1,2,4-Trichlorobenzene MR 2 1994
cis-1,2-Dichloroethylene MR 2 1994
DICHLOROMETHANE MR 2 1994
1,1-Dichloroethylene MR 2 1994
1,2-Dichloroethane MR 2 1994
Carbon tetrachloride MR 2 1994
1,2-Dichloropropane MR 2 1994
Tetrachloroethylene MR 2 1994
Benzene MR 2 1994
Styrene MR 2 1994
Trichloroethylene MR 2 1994
Toluene MR 2 1994
1,1,1-Trichloroethane MR 2 1994
1,1,2-Trichloroethane MR 2 1994
o-Dichlorobenzene MR 2 1994
Xylenes, Total MR 2 1994
trans-1,2-Dichloroethylene MR 2 1994
Vinyl chloride MR 2 1994
Ethylbenzene MR 2 1994
p-Dichlorobenzene MR 2 1994
CHLOROBENZENE MR 2 1994
Surface Water Treatment Rule TT 1 1992

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Groveton Water Sys.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID NH1781010 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

New Hampshire Drinking Water Authority

New Hampshire's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find NH regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2008 Consumer Confidence Rule Other 6 SDWIS / NH1781010 / 7000
2006 Chlorine MR 3 SDWIS / NH1781010 / 0999
1994 Nitrate MR 8 SDWIS / NH1781010 / 1040
1994 1,2,4-Trichlorobenzene MR 2 SDWIS / NH1781010 / 2378
1994 cis-1,2-Dichloroethylene MR 2 SDWIS / NH1781010 / 2380
1994 DICHLOROMETHANE MR 2 SDWIS / NH1781010 / 2964
1994 1,1-Dichloroethylene MR 2 SDWIS / NH1781010 / 2977
1994 1,2-Dichloroethane MR 2 SDWIS / NH1781010 / 2980
1994 Carbon tetrachloride MR 2 SDWIS / NH1781010 / 2982
1994 1,2-Dichloropropane MR 2 SDWIS / NH1781010 / 2983
1994 Tetrachloroethylene MR 2 SDWIS / NH1781010 / 2987
1994 Benzene MR 2 SDWIS / NH1781010 / 2990
1994 Styrene MR 2 SDWIS / NH1781010 / 2996
1994 Trichloroethylene MR 2 SDWIS / NH1781010 / 2984
1994 Toluene MR 2 SDWIS / NH1781010 / 2991

How Groveton Water Sys Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Groveton Water Sys New Hampshire avg Federal benchmark
Total violations 79 63.6 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 11 12.1 Indicates a contaminant exceeded a federal MCL
PFAS detection None 45.1% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 2,650 506 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,453 regulated public water systems in New Hampshire.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Groveton Water Sys water safe to drink? ▼
Groveton Water Sys (PWS ID: NH1781010) has 79 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 2,650 people using Groundwater sources.
How many people does Groveton Water Sys serve? ▼
Groveton Water Sys serves 2,650 people in Northumberland, New Hampshire. It is a Local-owned system using Groundwater water sources with 765 service connections.
What type of violations does Groveton Water Sys have? ▼
Groveton Water Sys has 79 total violations: 11 health-based violations (MCL exceedances or treatment failures), 57 monitoring/reporting violations, and 1 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Groveton Water Sys water? ▼
No PFAS testing data is available for Groveton Water Sys under the EPA's UCMR5 monitoring program.
What water source does Groveton Water Sys use? ▼
Groveton Water Sys uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.