Is Carroll, CT Tap Water Safe to Drink?
Graded C — but Lead and Copper were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
64.5/100
waterverge.com Carroll, CT — Water Quality Report
Carroll's drinking water received a grade of C (64.5 out of 100), indicating fair water quality. The city's 1 water system serves approximately 1,050 residents using groundwater.
Lead levels were measured at 48.0 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 62 violations on record, including 9 health-based violations. 7 remain unresolved.
What to know about Carroll's water
Carroll ranks #57 out of 158 cities in Connecticut for water quality, placing it mid-range in the state.
Carroll 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, Carroll may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Carroll, CT water safe to drink?
Carroll's drinking water has significant quality concerns based on EPA testing data. With a grade of C (64.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 1,050 residents using groundwater (wells).
Recent water quality updates for Carroll
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Carroll's water quality assessment. Grade: C (64.5/100).
Contaminants: Lead and Copper Rule.
Contaminants: Public Notice.
1 health-based. Contaminants: Lead and Copper Rule.
Key contaminant findings
Based on the most recent EPA sampling data for Carroll's water supply.
Exceeds EPA action level. Lead service line replacement and point-of-use filtration recommended.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Carroll's water system has 62 total violations on record, including 9 health-based violations. 7 remain unresolved. 5 violations were issued in the last 5 years.
Where does Carroll's water come from?
Carroll's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,050 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Pootatuck River (river), Pomperaug River (river), Housatonic River (river), Naugatuck River (river), Saugatuck R Below Saugatuck Res Nr Lyons Plain (river).
What Carroll residents can do
Recommended: NSF 53-certified pitcher or under-sink filter. This addresses the specific contaminants found in Carroll'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 Carroll'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. | 48.0 | 15 | ppb | Inorganic | Over Limit |
| 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. | 2.95 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level trend (90th percentile)
See how Carroll compares by contaminant
Explore where Carroll ranks among all Connecticut cities for specific contaminants.
Water source & infrastructure
Where Carroll's water comes from
Carroll'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 1,050 people through 1 water system.
Water bodies near Carroll
Carroll is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Carroll
| System Name | PWSID | Population | Source |
|---|---|---|---|
| ROSEBROOK WATER | NH0382010 | 1,050 | GW |
How Carroll compares
Full Connecticut rankings →Carroll's score of 64.5/100 is above the average of 47/100 among major Connecticut cities. It outscores 9 of 10 nearby cities.
Nearby cities
View Connecticut rankings →About Carroll, CT
Wikipedia →Monroe is a town located in eastern Fairfield County, Connecticut, United States. The population was 18,825 at the 2020 census. Monroe is part of the Greater Bridgeport Planning Region.
Learn more about your water
Guides and resources related to Carroll's water quality findings.
Explore water quality across Coos
Frequently asked questions
Is Carroll, CT tap water safe to drink?
Carroll's water quality earned a grade of C (64.5/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #57 out of 158 cities tested in Connecticut.
What contaminants are in Carroll's water?
Lead was measured at 48.0 ppb (90th percentile). 62 violations are on record.
How is Carroll'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 Carroll?
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 Carroll's water come from?
Carroll's water is sourced from Groundwater. The city has 1 water system serving approximately 1,050 residents.
What health violations has Carroll's water system had?
Carroll has 9 health-based violations on record. The most recent violation was recorded in January 2022. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 7 violations remain unresolved.
Is Carroll's groundwater at risk of contamination?
Carroll 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 62 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 Carroll's water compare to other cities?
Carroll ranks #57 out of 158 cities in Connecticut (better than 64% of state cities) and #11652 out of 15744 cities nationally (26th percentile). The grade of C reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Carroll's small water system affect quality?
Carroll's system serves approximately 1,050 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 62 violations on record.