Is Dubuque, CO Tap Water Safe to Drink?
Graded A, with 1 unresolved violation on record. See what was cited — and what it means for your tap. What to do next ↓
90.4/100
waterverge.com Dubuque, CO — Water Quality Report
Dubuque's drinking water received a grade of A (90.4 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 548 residents using purchased ground 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 8 violations on record, including 0 health-based violations. 1 remains unresolved.
What to know about Dubuque's water
Dubuque ranks #17 out of 246 cities in Colorado for water quality, placing it one of the best in the state.
Dubuque purchases its water from a regional wholesaler, meaning quality depends on both the supplier's treatment and the local distribution system's condition.
As a small community water system, Dubuque may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 6 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Dubuque, CO water safe to drink?
Dubuque's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (90.4/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 548 residents using groundwater (wells).
Recent water quality updates for Dubuque
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Dubuque's water quality assessment. Grade: A (90.4/100).
Contaminants: TTHM, Total Haloacetic Acids (HAA5).
Contaminants: TTHM, Total Haloacetic Acids (HAA5).
Contaminants: Total Haloacetic Acids (HAA5), TTHM.
Key contaminant findings
Based on the most recent EPA sampling data for Dubuque's water supply.
Well within EPA limits.
Violation history
Dubuque's water system has 8 total violations on record, including 0 health-based violations. 1 remain unresolved. 6 violations were issued in the last 5 years.
Where does Dubuque's water come from?
Dubuque's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 548 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Lee Gulch (river), Dutch (river), South Platte River Below Union Ave, (river), Little Dry Creek Nr Arapahoe (river), Little Dry Creek Above Englewood (river).
What Dubuque 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. | 0.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Dubuque compares by contaminant
Explore where Dubuque ranks among all Colorado cities for specific contaminants.
Water source & infrastructure
Where Dubuque's water comes from
Dubuque purchases its water supply from a regional wholesale provider rather than treating raw water directly.
Water quality depends on both the wholesaler's treatment standards and the condition of Dubuque's local distribution pipes and storage facilities.
Purchased water systems are common in suburban areas and smaller communities that lack the infrastructure for independent treatment.
The system is operated by private ownership and serves approximately 548 people through 1 water system.
Water bodies near Dubuque
Dubuque is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Dubuque
| System Name | PWSID | Population | Source |
|---|---|---|---|
| TERRACE HEIGHTS | IA3126604 | 548 | GWP |
How Dubuque compares
Full Colorado rankings →Dubuque's score of 90.4/100 is above the average of 45/100 among major Colorado cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Colorado rankings →About Dubuque, CO
Wikipedia →Denver is the capital and most populous city of the U.S. state of Colorado. Officially a consolidated city and county, it is located in the South Platte River valley on the western edge of the High Plains, and is just east of the Front Range of the Rocky Mountains (Rockies). Denver is the 19th-most populous city in the United States and the fifth-most populous state capital, with a population of 715,522 at the 2020 census. The ten-county Denver metropolitan area, with over 3.05 million residents, is the 19th-largest metropolitan area in the country and functions as the economic and cultural center of the broader Front Range Urban Corridor.
Learn more about your water
Guides and resources related to Dubuque's water quality findings.
Explore water quality across Dubuque
Frequently asked questions
Is Dubuque, CO tap water safe to drink?
Dubuque's water quality earned a grade of A (90.4/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #17 out of 246 cities tested in Colorado.
What contaminants are in Dubuque's water?
Lead was measured at 0.0 ppb (90th percentile). 8 violations are on record.
How is Dubuque'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 Dubuque?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Dubuque's water come from?
Dubuque's water is sourced from Purchased ground water. The city has 1 water system serving approximately 548 residents.
Is Dubuque's groundwater at risk of contamination?
Dubuque 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 8 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 Dubuque's water compare to other cities?
Dubuque ranks #17 out of 246 cities in Colorado (better than 93% of state cities) and #2267 out of 15744 cities nationally (86th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Dubuque's small water system affect quality?
Dubuque's system serves approximately 548 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 8 violations on record.