Is Bolton, MA Tap Water Safe to Drink?
Graded B+ — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
81.1/100
waterverge.com Bolton, MA — Water Quality Report
Bolton's drinking water received a grade of B+ (81.1 out of 100), indicating good water quality. The city's 5 water systems serve approximately 1,173 residents using groundwater.
Lead levels were measured at 1.3 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 42 violations on record, including 4 health-based violations. 13 remain unresolved.
What to know about Bolton's water
Bolton ranks #161 out of 280 cities in Massachusetts for water quality, placing it below average in the state.
Bolton 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.
As a small community water system, Bolton may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Bolton, MA water safe to drink?
Bolton's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (81.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 5 water systems serve approximately 1,173 residents using groundwater (wells).
Recent water quality updates for Bolton
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Bolton's water quality assessment. Grade: B+ (81.1/100).
Contaminants: Lead and Copper Rule.
Contaminants: Revised Total Coliform Rule.
Contaminants: Revised Total Coliform Rule.
Key contaminant findings
Based on the most recent EPA sampling data for Bolton's water supply.
Well within EPA limits.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Bolton's water system has 42 total violations on record, including 4 health-based violations. 13 remain unresolved.
Where does Bolton's water come from?
Bolton's drinking water comes from groundwater (wells), supplied by 5 water systems serving approximately 1,173 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Bolton residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Bolton'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.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Drought conditions
D1 — moderate droughtWorcester County is currently in D1 (moderate 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 Bolton'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. | 1.3 | 15 | ppb | Inorganic | Safe |
| Copper (90th percentile) CopperInorganic A metal that enters drinking water mainly through corrosion of copper plumbing. Small amounts are essential for health, but excess levels are harmful. Health EffectsGastrointestinal distress (nausea, vomiting, diarrhea) at short-term high levels; liver and kidney damage from long-term exposure. EPA Limit1.3 mg/L action level Common SourcesCorrosion of copper household plumbing, erosion of natural deposits. | 3.30 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level (90th percentile)
Latest reading: 3.300 mg/L (2007)
EPA action level: 1.3 mg/L
See how Bolton compares by contaminant
Explore where Bolton ranks among all Massachusetts cities for specific contaminants.
Water source & infrastructure
Where Bolton's water comes from
Bolton'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 private ownership and serves approximately 1,173 people through 5 water systems.
Water systems serving Bolton
| System Name | PWSID | Population | Source |
|---|---|---|---|
| BOLTON OFFICE PARK ALTA NASHOBA VALLEY | MA2034019 | 788 | GW |
| REGENCY AT BOLTON CONDOMINIUMS | MA2034030 | 148 | GW |
| CENTURY MILL ESTATES | MA2034031 | 135 | GW |
| BOLTON COUNTRY MANOR | MA2034027 | 60 | GW |
| SUNSET RIDGE CONDOMINIUMS | MA2034028 | 42 | GW |
How Bolton compares
Full Massachusetts rankings →Bolton's score of 81.1/100 is on par with the average of 80/100 among major Massachusetts cities. It outscores 5 of 10 nearby cities.
Nearby cities
View Massachusetts rankings →Learn more about your water
Guides and resources related to Bolton's water quality findings.
Explore water quality across Worcester
Frequently asked questions
Is Bolton, MA tap water safe to drink?
Bolton's water quality earned a grade of B+ (81.1/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #161 out of 280 cities tested in Massachusetts.
What contaminants are in Bolton's water?
Lead was measured at 1.3 ppb (90th percentile). 42 violations are on record.
How is Bolton'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 Bolton?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Bolton's water come from?
Bolton's water is sourced from Groundwater. The city has 5 water systems serving approximately 1,173 residents.
What health violations has Bolton's water system had?
Bolton has 4 health-based violations on record. The most recent violation was recorded in July 2020. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 13 violations remain unresolved.
Is Bolton's groundwater at risk of contamination?
Bolton 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 42 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 Bolton's water compare to other cities?
Bolton ranks #161 out of 280 cities in Massachusetts (better than 43% of state cities) and #7599 out of 15744 cities nationally (52th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.