Is Hopkinton, CT Tap Water Safe to Drink?
Graded F — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
41/100
waterverge.com Hopkinton, CT — Water Quality Report
Hopkinton's drinking water received a grade of F (41 out of 100), indicating failing water quality. The city's 5 water systems serve approximately 769 residents using groundwater.
Lead levels were measured at 4.0 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 266 violations on record, including 37 health-based violations. 72 remain unresolved.
What to know about Hopkinton's water
Hopkinton ranks #135 out of 158 cities in Connecticut for water quality, placing it among the lowest-rated in the state.
Hopkinton 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, Hopkinton may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 187 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Hopkinton, CT water safe to drink?
Hopkinton's drinking water has significant quality concerns based on EPA testing data. With a grade of F (41/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 5 water systems serve approximately 769 residents using groundwater (wells).
Recent water quality updates for Hopkinton
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Hopkinton's water quality assessment. Grade: F (41/100).
Contaminants: Consumer Confidence Rule.
Contaminants: Revised Total Coliform Rule, Lead and Copper Rule.
Contaminants: Lead and Copper Rule.
Key contaminant findings
Based on the most recent EPA sampling data for Hopkinton'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
Hopkinton's water system has 266 total violations on record, including 37 health-based violations. 72 remain unresolved. 187 violations were issued in the last 5 years.
Where does Hopkinton's water come from?
Hopkinton's drinking water comes from groundwater (wells), supplied by 5 water systems serving approximately 769 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Pawcatuck River (river), Wood River (river), Pendleton Hill Brook (river).
What Hopkinton residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Hopkinton'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
Recommended water filters
Based on contaminants detected in Hopkinton'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. | 4.0 | 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. | 1.54 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level trend (90th percentile)
See how Hopkinton compares by contaminant
Explore where Hopkinton ranks among all Connecticut cities for specific contaminants.
Water source & infrastructure
Where Hopkinton's water comes from
Hopkinton'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 769 people through 5 water systems.
Water bodies near Hopkinton
Hopkinton is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Hopkinton
| System Name | PWSID | Population | Source |
|---|---|---|---|
| LINDHBROOK WATER COMPANY | RI1000098 | 200 | GW |
| BETHEL VILLAGE WATER ASSN | RI1000045 | 180 | GW |
| CANONCHET CLIFFS WATER ASSOCIATION INC. | RI1900053 | 154 | GW |
| HOPKINTON, TOWN OF | RI2980473 | 125 | GWP |
| SAUGATUCKET SPRINGS | RI2980423 | 110 | GW |
How Hopkinton compares
Full Connecticut rankings →Hopkinton's score of 41/100 is below the average of 47/100 among major Connecticut cities. It outscores 3 of 10 nearby cities. 6 of 10 nearby cities score higher.
Nearby cities
View Connecticut rankings →About Hopkinton, CT
Wikipedia →Ashaway is an unincorporated village and census-designated place (CDP) in the town of Hopkinton, Rhode Island, United States. It is a principal village of Hopkinton, along with Hope Valley, although it is the smaller of the two. The population was 1,485 at the 2010 census. The name Ashaway is derived from the American Indian name for the river that runs through the village, the Ashawague or Ashawaug, which means "land in the middle" or "land between" in the Niantic and Mohegan languages. The name "Ashawague River" appears as late as 1832 on the Findley map of Rhode Island published in Philadelphia.
Learn more about your water
Guides and resources related to Hopkinton's water quality findings.
Explore water quality across Washington
Frequently asked questions
Is Hopkinton, CT tap water safe to drink?
Hopkinton's water quality earned a grade of F (41/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #135 out of 158 cities tested in Connecticut.
What contaminants are in Hopkinton's water?
Lead was measured at 4.0 ppb (90th percentile). 266 violations are on record.
How is Hopkinton'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 Hopkinton?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Hopkinton's water come from?
Hopkinton's water is sourced from Groundwater. The city has 5 water systems serving approximately 769 residents.
What health violations has Hopkinton's water system had?
Hopkinton has 37 health-based violations on record. The most recent violation was recorded in July 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 72 violations remain unresolved.
Is Hopkinton's groundwater at risk of contamination?
Hopkinton 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 266 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 Hopkinton's water compare to other cities?
Hopkinton ranks #135 out of 158 cities in Connecticut (better than 15% of state cities) and #15082 out of 15744 cities nationally (4th percentile). The grade of F reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.