Is Derby, QC Tap Water Safe to Drink?
Graded A, with 2 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
91.6/100
waterverge.com Derby, QC — Water Quality Report
Derby's drinking water received a grade of A (91.6 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 897 residents using groundwater.
Lead levels were measured at 1.2 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 11 violations on record, including 1 health-based violation. 2 remain unresolved.
What to know about Derby's water
Derby ranks #1 out of 1 cities in QC for water quality, placing it one of the best in the state.
Derby 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, Derby may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Derby, QC water safe to drink?
Derby's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (91.6/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 897 residents using groundwater (wells).
Recent water quality updates for Derby
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Derby's water quality assessment. Grade: A (91.6/100).
Contaminants: Consumer Confidence Rule.
Contaminants: Lead and Copper Rule.
Contaminants: Revised Total Coliform Rule.
Key contaminant findings
Based on the most recent EPA sampling data for Derby's water supply.
Well within EPA limits.
Violation history
Derby's water system has 11 total violations on record, including 1 health-based violation. 2 remain unresolved. 2 violations were issued in the last 5 years.
Where does Derby's water come from?
Derby's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 897 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Derby residents can do
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
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. | 1.2 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Derby compares by contaminant
Explore where Derby ranks among all QC cities for specific contaminants.
Water source & infrastructure
Where Derby's water comes from
Derby'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 897 people through 1 water system.
Water systems serving Derby
| System Name | PWSID | Population | Source |
|---|---|---|---|
| DERBY LINE VILLAGE WATER DISTRICT | VT0020568 | 897 | GW |
About Derby, QC
Wikipedia →Stanstead is a town in the Memphrémagog Regional County Municipality in the Estrie region of Quebec, located on the Canada–United States border across from Derby Line, Vermont.
Learn more about your water
Guides and resources related to Derby's water quality findings.
Explore water quality across Orleans
Frequently asked questions
Is Derby, QC tap water safe to drink?
Derby's water quality earned a grade of A (91.6/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #1 out of 1 cities tested in QC.
What contaminants are in Derby's water?
Lead was measured at 1.2 ppb (90th percentile). 11 violations are on record.
How is Derby'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 Derby?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Derby's water come from?
Derby's water is sourced from Groundwater. The city has 1 water system serving approximately 897 residents.
What health violations has Derby's water system had?
Derby has 1 health-based violation on record. The most recent violation was recorded in July 2023. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 2 violations remain unresolved.
Is Derby's groundwater at risk of contamination?
Derby 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 11 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 Derby's water compare to other cities?
Derby ranks #1 out of 1 cities in QC (better than 0% of state cities) and #1612 out of 15744 cities nationally (90th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Derby's small water system affect quality?
Derby's system serves approximately 897 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 11 violations on record.