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GREAT BAY WATER SYSTEM

PWS ID: NH1732030 · NASHUA, New Hampshire 03064

GREAT BAY WATER SYSTEM serves 218 people in NASHUA, New Hampshire using Groundwater water sources. It has 592 recorded EPA violations, including 31 health-based violations. No PFAS contamination was detected in UCMR5 testing.

Water Quality Snapshot: GREAT BAY WATER SYSTEM

GREAT BAY WATER SYSTEM is a private-owned community water system that delivers drinking water to 218 residents in NASHUA, New Hampshire (Rockingham County) through 87 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 592 total violations for this system , of which 31 (5%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 561 monitoring and reporting violations are on file. The most recent violation on record dates to 2009.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 27 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. GREAT BAY WATER SYSTEM's 592 violations sit above the New Hampshire average. Statewide, 23 of 51 UCMR5-tested systems have reported PFAS detections (45.1%). 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
218
Total Violations
592
Health-Based Violations
31
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
87
County
Rockingham
School/Daycare
No
MCL Violations
31
Monitoring Violations
561
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MCL 27 2009
Coliform (TCR) MR 27 1994
Xylenes, Total MR 14 1998
p-Dichlorobenzene MR 14 1998
Vinyl chloride MR 14 1998
1,2-Dichloroethane MR 14 1998
Carbon tetrachloride MR 14 1998
Trichloroethylene MR 14 1998
1,1,2-Trichloroethane MR 14 1998
Benzene MR 14 1998
1,2,4-Trichlorobenzene MR 14 1998
cis-1,2-Dichloroethylene MR 14 1998
o-Dichlorobenzene MR 14 1998
trans-1,2-Dichloroethylene MR 14 1998
1,1,1-Trichloroethane MR 14 1998
1,2-Dichloropropane MR 14 1998
Tetrachloroethylene MR 14 1998
CHLOROBENZENE MR 14 1998
Toluene MR 14 1998
Ethylbenzene MR 14 1998
Styrene MR 14 1998
1,1-Dichloroethylene MR 14 1998
DICHLOROMETHANE MR 14 1998
Endrin MR 9 1998
BHC-GAMMA MR 9 1998
Methoxychlor MR 9 1998
Glyphosate MR 9 1998
Hexachlorocyclopentadiene MR 9 1998
Carbofuran MR 9 1998
Atrazine MR 9 1998

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 GREAT BAY WATER SYSTEM.

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 NH1732030 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
2009 Coliform (TCR) MCL 27 SDWIS / NH1732030 / 3100
2004 Gross Alpha, Excl. Radon and U MCL 2 SDWIS / NH1732030 / 4000
2004 Combined Radium (-226 and -228) MCL 2 SDWIS / NH1732030 / 4010
1998 Xylenes, Total MR 14 SDWIS / NH1732030 / 2955
1998 p-Dichlorobenzene MR 14 SDWIS / NH1732030 / 2969
1998 Vinyl chloride MR 14 SDWIS / NH1732030 / 2976
1998 1,2-Dichloroethane MR 14 SDWIS / NH1732030 / 2980
1998 Carbon tetrachloride MR 14 SDWIS / NH1732030 / 2982
1998 Trichloroethylene MR 14 SDWIS / NH1732030 / 2984
1998 1,1,2-Trichloroethane MR 14 SDWIS / NH1732030 / 2985
1998 Benzene MR 14 SDWIS / NH1732030 / 2990
1998 1,2,4-Trichlorobenzene MR 14 SDWIS / NH1732030 / 2378
1998 cis-1,2-Dichloroethylene MR 14 SDWIS / NH1732030 / 2380
1998 o-Dichlorobenzene MR 14 SDWIS / NH1732030 / 2968
1998 trans-1,2-Dichloroethylene MR 14 SDWIS / NH1732030 / 2979

How GREAT BAY WATER SYSTEM Compares

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

Metric GREAT BAY WATER SYSTEM New Hampshire avg Federal benchmark
Total violations 592 63.6 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 31 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 218 506 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
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is GREAT BAY WATER SYSTEM water safe to drink? ▼
GREAT BAY WATER SYSTEM (PWS ID: NH1732030) has 592 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 218 people using Groundwater sources.
How many people does GREAT BAY WATER SYSTEM serve? ▼
GREAT BAY WATER SYSTEM serves 218 people in NASHUA, New Hampshire. It is a Private-owned system using Groundwater water sources with 87 service connections.
What type of violations does GREAT BAY WATER SYSTEM have? ▼
GREAT BAY WATER SYSTEM has 592 total violations: 31 health-based violations (MCL exceedances or treatment failures), 561 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in GREAT BAY WATER SYSTEM water? ▼
No PFAS testing data is available for GREAT BAY WATER SYSTEM under the EPA's UCMR5 monitoring program.
What water source does GREAT BAY WATER SYSTEM use? ▼
GREAT BAY WATER SYSTEM 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.

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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.

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Data sourced from $official public datasets. See our methodology for details. Retrieved and formatted by PlainWater Editorial