Nashua, NH Water Safety: 81/100 (2026)
5 ZIP codes · 5 water systems · Updated 2026-06-03
How does Nashua tap water hold up under EPA scrutiny? Above average for NH — documented violations are uncommon and the safety grade reflects a clean overall record.
How Nashua Compares
Data: EPA SDWIS Last verified: 2026-06-03
Water Quality Map: Nashua, NH
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Score Distribution
Safety grade breakdown for Nashua's 5 ZIP codes.
Key Facts for Nashua Residents
- Average lead level: 0.002 mg/L.
- Homes built before 1986: 75% — older plumbing may contain lead solder.
- Estimated remediation: $1,360 per household.
- CDC health risk index: 11.54.
Nashua's Water Providers
Water supply in Nashua, NH follows a divided structure: 3 utilities account for the largest share of residential service out of 5 total systems, each managing its own distribution network and EPA reporting. Because these systems operate independently, rate decisions and compliance outcomes are determined separately.
Overview
We track water quality and home safety data for 5 ZIP codes in Nashua, New Hampshire, covering 5 community water systems serving approximately 91,131 people.
No EPA violations recorded across any ZIP codes in Nashua — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Nashua: B (81/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Nashua water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0020 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 5 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 03060 | B | Pennichuck Water Works | 89,073 |
| 03061 | B | Pennichuck Water Works | 89,073 |
| 03062 | B | Pennichuck Water Works | 89,073 |
| 03063 | B | Pennichuck Water Works | 89,073 |
| 03064 | B | Pennichuck Water Works | 89,073 |
All ZIP Codes in Nashua
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
Nashua Community Health Snapshot
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Nashua Infrastructure Age
With 75% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
The lead that enters tap water in older homes often comes not from the municipal supply but from the home's own plumbing — from solder used in copper joints before the 1986 federal ban, or from lead pipes installed before 1970. In Nashua, where the median build year is 1971, these older materials are widespread. More than half the residential stock predates the 1986 solder ban, and a significant fraction predates 1970 as well. For residents in those homes, the city-wide water quality picture is a less relevant frame than the specific materials inside their own walls and under their own street.
Over half of homes in Nashua were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
How Remediation Costs Compare in Nashua
When remediation costs are measured against Nashua home values, the resulting ratio is in the low tier — addressing documented water and safety issues here claims only a minor fraction of typical equity, and most homeowners are in a position where the financial commitment is straightforward rather than a material burden on their household budget.
Remediation costs in Nashua are relatively low compared to home values. The $640–$2,240 estimated range is a small fraction of median property value. Home values are 5% above the New Hampshire average.
Nashua: Lead Risk & Vulnerable Populations
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Locally, 75% of Nashua homes carry interior plumbing from the era when lead solder was still permitted in new builds, and citywide monitoring approaches or crosses the EPA action benchmark. Households can find a draw-test kit and certified filtration through verified retailers.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Nashua: Flood History & Water Damage Risk
Flood history in Nashua spans 68 NFIP claims and 80% flood zone coverage — enough to place it in moderate-exposure territory where flood events are genuinely recurring rather than statistical outliers. That distinction matters for water quality assessment because the connection between flooding and water safety is not uniform across communities. In low-exposure areas, flooding rarely generates the conditions needed to compromise treatment or distribution infrastructure. In high-exposure areas, it can do so repeatedly. Moderate-exposure communities sit in between: flood events occur with enough frequency to make periodic infrastructure stress a reasonable concern, particularly for private well owners and residents in lower-elevation FEMA-designated zones.
Nashua has a moderate flood history with 68 FEMA claims averaging $7,579 per payout. 80% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$1,360</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
Deep Dive Reports
Detailed analysis for Nashua, NH