D32/100
PORTSMOUTH WATER WORKS — Water Quality Report 2026
Serving 33,000 people · New Hampshire
Water Source
Surface Water
County
—
System ID
NH1951010
Violations
12
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 1.43 mg/L | 1.30 mg/L | Over Limit |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2014.
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Frequently Asked Questions About PORTSMOUTH WATER WORKS
Is PORTSMOUTH WATER WORKS water safe to drink?
PORTSMOUTH WATER WORKS water receives a grade of D (32/100), which is considered poor. 1 contaminant(s) exceed EPA legal limits and 12 violation(s) are on record. Customers may want to consider using a water filter.
What contaminants has PORTSMOUTH WATER WORKS detected?
70 contaminants were tested in PORTSMOUTH WATER WORKS's water. Notable contaminants include Copper (90th percentile). 1 exceed EPA legal limits (MCLs). 1 exceed EPA health goals (MCLGs).
Does PORTSMOUTH WATER WORKS have any EPA violations?
Yes, PORTSMOUTH WATER WORKS has 12 EPA violation(s) on record, with the most recent in 2014. Violation types include MCL, TT. 12 are health-based violations.
How many people does PORTSMOUTH WATER WORKS serve?
PORTSMOUTH WATER WORKS serves approximately 33,000 people, New Hampshire. The system provides water to 1 community: Portsmouth.
What type of water does PORTSMOUTH WATER WORKS provide?
PORTSMOUTH WATER WORKS sources its water from surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is NH1951010.
How does PORTSMOUTH WATER WORKS compare to other utilities in New Hampshire?
PORTSMOUTH WATER WORKS scores 32/100 with a grade of D (poor). This score suggests significant water quality concerns relative to other utilities. Visit our New Hampshire state page for a full comparison of water systems.