Is Northumberland, NH Tap Water Safe to Drink?
Graded C+ — but Lead was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
69.3/100
Northumberland, NH — Water Quality Report
Northumberland's drinking water received a grade of C+ (69.3 out of 100), indicating fair water quality. The city's 2 water systems serve approximately 2,715 residents using groundwater.
Lead levels were measured at 168.0 ppb (90th percentile), which exceeds the EPA action level of 15 ppb. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 43 violations on record, including 4 health-based violations. 9 remain unresolved.
What to know about Northumberland's water
Northumberland ranks #51 out of 119 cities in New Hampshire for water quality, placing it mid-range in the state.
Northumberland relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
Lead levels exceed the EPA action level of 15 ppb, which typically indicates aging lead service lines or lead solder in the distribution system. An NSF 53-certified filter is strongly recommended for drinking and cooking water.
As a small community water system, Northumberland may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Northumberland, NH water safe to drink?
Northumberland's drinking water has significant quality concerns based on EPA testing data. With a grade of C+ (69.3/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 2,715 residents using groundwater (wells).
Recent water quality updates for Northumberland
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Northumberland's water quality assessment. Grade: C+ (69.3/100).
Contaminants: Revised Total Coliform Rule.
Contaminants: Consumer Confidence Rule.
Contaminants: Consumer Confidence Rule.
Key contaminant findings
Based on the most recent EPA sampling data for Northumberland's water supply.
Exceeds EPA action level. Lead service line replacement and point-of-use filtration recommended.
Violation history
Northumberland's water system has 43 total violations on record, including 4 health-based violations. 9 remain unresolved.
Where does Northumberland's water come from?
Northumberland's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 2,715 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Upper Ammonoosuc River (river).
What Northumberland residents can do
Recommended: NSF 53-certified pitcher or under-sink filter. This addresses the specific contaminants found in Northumberland's water.
Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Drought conditions
D2 — severe droughtCoos County is currently in D2 (severe drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.
Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.
Recommended water filters
Based on contaminants detected in Northumberland's water supply, we recommend the following filter types.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 168.0 | 15 | ppb | Inorganic | Over Limit |
Lead level trend (90th percentile)
See how Northumberland compares by contaminant
Explore where Northumberland ranks among all New Hampshire cities for specific contaminants.
Water source & infrastructure
Where Northumberland's water comes from
Northumberland's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by local government ownership and serves approximately 2,715 people through 2 water systems.
Water bodies near Northumberland
Northumberland is located near 1 notable water body. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Northumberland
| System Name | PWSID | Population | Source |
|---|---|---|---|
| GROVETON WATER SYS | NH1781010 | 2,650 | GW |
| LOST NATION WATER | NH1781030 | 65 | GW |
How Northumberland compares
Full New Hampshire rankings →Northumberland's score of 69.3/100 is on par with the average of 69/100 among major New Hampshire cities. It outscores 4 of 10 nearby cities. 6 of 10 nearby cities score higher.
Nearby cities
View New Hampshire rankings →About Northumberland, NH
Learn more about your water
Guides and resources related to Northumberland's water quality findings.
Explore water quality across Coos
Frequently asked questions
Is Northumberland, NH tap water safe to drink?
Northumberland's water quality earned a grade of C+ (69.3/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #51 out of 119 cities tested in New Hampshire.
What contaminants are in Northumberland's water?
Lead was measured at 168.0 ppb (90th percentile). 43 violations are on record.
How is Northumberland's water quality grade calculated?
The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.
Do I need a water filter in Northumberland?
Yes — lead levels exceed the EPA action level of 15 ppb. We recommend an NSF 53-certified filter or reverse osmosis system. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Northumberland's water come from?
Northumberland's water is sourced from Groundwater. The city has 2 water systems serving approximately 2,715 residents.
What health violations has Northumberland's water system had?
Northumberland has 4 health-based violations on record. The most recent violation was recorded in September 2020. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 9 violations remain unresolved.
Is Northumberland's groundwater at risk of contamination?
Northumberland uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 43 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
How does Northumberland's water compare to other cities?
Northumberland ranks #51 out of 119 cities in New Hampshire (better than 57% of state cities) and #10943 out of 15744 cities nationally (31th percentile). The grade of C+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.