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WaterVerge

Water quality report · updated Jul 2026

Is Durham, CT Tap Water Safe to Drink?

Graded D, with 119 unresolved violations on record. See what was cited — and what it means for your tap. What to do ↓

0 contaminants over a legal limit
0.0 ppb lead, 90th percentile · low
119 unresolved violations
2K people served by 7 water systems

PWSID CT0380021 · moderate data confidence · local government utility

Reviewed by WaterVerge Editorial Team · Last updated July 2026
D 49 / 100

#86 of 129Connecticut cities
How we grade →

01The verdict: is Durham water safe?

Durham's drinking water has significant quality concerns based on EPA testing data. With a grade of D (49/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 7 water systems serve approximately 2,024 residents using surface water (rivers, lakes, or reservoirs).

The concern

119 unresolved violations on record

EPA records show open compliance items for this system. Most are administrative, but unresolved items are worth watching.

See what was cited ↓
The good news

Lead is well under the limit

90th-percentile lead is 0.0 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.

See the trend ↓
Keep watching

98 violations in the last five years

Recent compliance history is the best predictor of future problems — the year-by-year record is below.

See the record ↓

Durham's drinking water received a grade of D (49 out of 100), indicating poor water quality. The city's 7 water systems serve approximately 2,024 residents using purchased surface water.

Lead levels were measured at 0.0 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 664 violations on record, including 46 health-based violations. 119 remain unresolved.

Durham ranks #86 out of 129 cities in Connecticut for water quality, placing it below average in the state. The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection. As a small community water system, Durham may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities. The system has seen 98 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

How the 49/100 breaks down Methodology →
ViolationsHistorical violation record including health-based and monitoring violations.
0 / 45F
Lead & CopperLead at 0.0 ppb (90th percentile).
20 / 20A
ContaminantsPFAS + legacy contaminant analysis.
17 / 20B
ComplianceMonitoring and reporting compliance with EPA regulations.
8 / 10B
Source RiskWater source: Purchased surface water.
4 / 5B

02What's in Durham's water

Every contaminant flagged in Durham, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.

1 detection · sorted by % of legal limit
Over the limit Elevated — watch Within limits
0 50% LEGAL LIMIT 150%
1 contaminant tested under EPA SDWIS, LCR and UCMR programs · 1 detected · not yet tested for PFAS under UCMR 5

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
Data source: EPA SDWIS, UCMR 5, local utility CCR.

03Durham's ten-year track record

Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 664 violations on record, including 46 health-based violations. 119 remain unresolved.

1 of the last ten years was clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.

8 health-based in 10 yrs 113 monitoring & paperwork 63 still unresolved
UpdateWater quality data updatedLatest EPA compliance and testing data incorporated into Durham's water quality assessment. Grade: D (49/100).
Violation1 drinking water violation recordedContaminants: Lead and Copper Rule.Open
Violation3 drinking water violations recorded1 health-based. Contaminants: Lead and Copper Rule, Revised Total Coliform Rule.Open
Violation1 drinking water violation recordedContaminants: Consumer Confidence Rule.Open
Lead, 90th percentileppb · lower is better
0100200300400500EPA action level · 15 ppb2000 — 26 ppb2001 — 360 ppb2002 — 0 ppb2003 — 12 ppb2004 — 0 ppb2005 — 3 ppb2006 — 0 ppb2007 — 1 ppb2008 — 0 ppb2009 — 8 ppb2010 — 7 ppb2011 — 6 ppb2012 — 4 ppb2013 — 4.6 ppb2014 — 0 ppb2015 — 2 ppb2016 — 2.2 ppb2017 — 9.6 ppb2018 — 1 ppb2019 — 0 ppb2020 — 0 ppb2021 — 0.90 ppb2022 — 0 ppb2023 — 1.9 ppb2024 — 2.4 ppb2025 — 1.4 ppb261.4200020062012201820242025

Down 25 ppb since 2000. Latest reading: 1.4 ppb (2025) — 9% of the action level. Sampled at higher-risk homes (90th percentile).

04Where Durham's water comes from

Durham's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Source

Purchased Surface Water

Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.

Treatment

Wholesale supplier

Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.

Distribution

7 systems

7 water systems, operated under local government ownership.

Delivery

2,024 people

Residents served across Durham's service area.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards. These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge. The system is operated by local government ownership and serves approximately 2,024 people through 7 water systems.

System namePWSIDPopulationSource
DURHAM CENTER DIVISION CT0380021 1,601 Purchased Surface Water
YESHIVA OF WATERBURY-DURHAM CAMPUS CT0380041 490 Groundwater
BLUE TRAILS WATER ASSOCIATION CT0990011 228 Groundwater
TWIN MAPLES NURSING HOME CT0381011 100 Groundwater
DURHAM ELDERLY HOUSING DIVISION CT0380641 50 Groundwater
DURHAM LEXINGTON PLACE DIVISION CT0380651 45 Groundwater
OLD INDIAN TRAIL CT0820501 32 Groundwater

Water bodies near Durham

Mattabesset River · river Coginchaug River · river Connecticut River Nr Boat House · stream Connecticut River · stream Farm River · river

As a surface-water system, these water bodies may directly influence Durham's drinking water supply.

05Pressure on Durham's watershed

Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.

Industrial discharge

Present — monitored

5 facilities within 10 miles reported 1k lb released to surface water in the latest EPA Toxics Release Inventory. Proximity doesn't equal tap contamination — treatment and hydrology decide — but it's pressure on the watershed.

ALLNEX USA INC. WALLINGFORD CT SITE — methanol 1k lb · 8.0 mi
MIDDLETOWN POWER LLC — ammonia 125 lb · 7.9 mi
TRADEBE TREATMENT & RECYCLING NORTHEAST LLC — nitrate compounds (water dissociable; reportable only when in aqueous solution) 50 lb · 8.1 mi
+ 2 more facilities

Superfund proximity

Low — tracked and monitored

1 National Priorities List site within 10 miles. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.

06How Durham compares

Scores for nearby Connecticut cities on one line, with the average marked.

Branford
85.4 · A-
Ansonia
82.4 · B+
Derby
80.2 · B+
Bethany
55.8 · C-
Durham (this city)
49 · D
Cheshire
35.5 · F

dashed line = Connecticut average (72/100)

Durham scores 49/100below the Connecticut average of 72/100. It outscores 2 of 10 nearby cities. Full Connecticut rankings →

Middlesex water quality rankings
Compare all cities in the county — grades, violations, and contaminant data side by side.

07What to do at home

Steps matched to what testing actually found in Durham's water — not generic advice.

Extra protection

A basic carbon filter still helps

Durham's water meets federal standards, but a simple carbon filter improves taste and adds a margin of safety against short-term issues.

Compare tested filters →
Know your report

Read your utility's annual report

Every utility must publish a yearly Consumer Confidence Report with its own testing results. It pairs well with the independent data on this page.

How to read a CCR →
Stay informed

Watch for Durham alerts

We refresh EPA data monthly and surface new violations, advisories, and boil-water notices for your county on this page.

All water alerts →

Frequently asked questions

Is Durham, CT tap water safe to drink?

Durham's water quality earned a grade of D (49/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #86 out of 129 cities tested in Connecticut.

What contaminants are in Durham's water?

Lead was measured at 0.0 ppb (90th percentile). 664 violations are on record.

How is Durham'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 Durham?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Durham's water come from?

Durham's water is sourced from Purchased surface water. The city has 7 water systems serving approximately 2,024 residents.

What health violations has Durham's water system had?

Durham has 46 health-based violations on record. The most recent violation was recorded in October 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 119 violations remain unresolved.

How does Durham's water compare to other cities?

Durham ranks #86 out of 129 cities in Connecticut (better than 33% of state cities) and #13094 out of 15382 cities nationally (15th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

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About Durham, CT: Durham is a town in Middlesex County, Connecticut, United States. Durham is a former farming village on the Coginchaug River in central Connecticut. The town is part of the Lower Connecticut River Valley Planning Region. The population was 7,152 at the 2020 census. Every autumn, the town hosts the Durham Fair, the largest volunteer agricultural fair in New England. Wikipedia → Sources: EPA SDWIS & ECHO · UCMR 3–5 · Lead & Copper Rule samples · EPA TRI · U.S. Drought Monitor · FEMA declarations. Data last updated Jul 2026. Analysis by the WaterVerge Editorial Team · methodology.