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Community Water System · PWS NH1661010

New Castle Water Works

Portsmouth, New Hampshire 03801 - drinking water served from surface water sources to 910 people, tracked in EPA SDWIS and UCMR5.

910
People served
115
EPA violations
83
Health-based
Untested
UCMR5 result

The verdict

EPA records 115 drinking-water violations at New Castle Water Works, 72% of them health-based - above the New Hampshire per-system average.

115
Total EPA violations on record
72%
Health-based (MCL / treatment failure)
910
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: New Castle Water Works

New Castle Water Works is a local-owned community water system that delivers drinking water to 910 residents in Portsmouth, New Hampshire (Rockingham County) through 365 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 115 total violations for this system , of which 83 (72%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 30 monitoring and reporting violations are on file. The most recent violation on record dates to 2023.

The most frequently cited contaminant at this system is TTHM, recorded in 66 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%).

New Castle Water Works's 115 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
910
Total Violations
115
Health-Based Violations
83
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Local
Connections
365
County
Rockingham
School/Daycare
No
MCL Violations
81
Monitoring Violations
30
Treatment Tech Violations
2

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
TTHM MCL 66 2018
Coliform (TCR) MCL 15 1995
Total Haloacetic Acids (HAA5) MR 8 2010
TTHM MR 8 2010
Chlorine MR 8 2016
Lead and Copper Rule MR 6 2023
Consumer Confidence Rule Other 2 2008
Lead and Copper Rule TT 2 1994

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 New Castle Water Works.

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 NH1661010 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
2023 Lead and Copper Rule MR 6 SDWIS / NH1661010 / 5000
2018 TTHM MCL 66 SDWIS / NH1661010 / 2950
2016 Chlorine MR 8 SDWIS / NH1661010 / 0999
2010 Total Haloacetic Acids (HAA5) MR 8 SDWIS / NH1661010 / 2456
2010 TTHM MR 8 SDWIS / NH1661010 / 2950
2008 Consumer Confidence Rule Other 2 SDWIS / NH1661010 / 7000
1995 Coliform (TCR) MCL 15 SDWIS / NH1661010 / 3100
1994 Lead and Copper Rule TT 2 SDWIS / NH1661010 / 5000

How New Castle Water Works Compares

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

Metric New Castle Water Works New Hampshire avg Federal benchmark
Total violations 115 63.6 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 83 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 910 506 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 New Castle Water Works water safe to drink? ▼
New Castle Water Works (PWS ID: NH1661010) has 115 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 910 people using Surface Water sources.
How many people does New Castle Water Works serve? ▼
New Castle Water Works serves 910 people in Portsmouth, New Hampshire. It is a Local-owned system using Surface Water water sources with 365 service connections.
What type of violations does New Castle Water Works have? ▼
New Castle Water Works has 115 total violations: 83 health-based violations (MCL exceedances or treatment failures), 30 monitoring/reporting violations, and 2 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in New Castle Water Works water? ▼
No PFAS testing data is available for New Castle Water Works under the EPA's UCMR5 monitoring program.
What water source does New Castle Water Works use? ▼
New Castle Water Works uses Surface Water 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.