Is Denver, IA Tap Water Safe to Drink?
Graded A, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
90.5/100
waterverge.com Denver, IA — Water Quality Report
Denver's drinking water received a grade of A (90.5 out of 100), indicating excellent water quality. The city's 2 water systems serve approximately 2,087 residents using groundwater.
Lead levels were measured at 0.6 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 14 violations on record, including 2 health-based violations. 3 remain unresolved.
What to know about Denver's water
Denver ranks #173 out of 436 cities in Iowa for water quality, placing it mid-range in the state.
Denver 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, Denver may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Denver, IA water safe to drink?
Denver's drinking water has significant quality concerns based on EPA testing data. With a grade of A (90.5/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 2,087 residents using groundwater (wells).
Recent water quality updates for Denver
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Denver's water quality assessment. Grade: A (90.5/100).
Contaminants: Revised Total Coliform Rule.
Federal disaster declaration (FEMA DR-4421). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-4289). Flood event — may have impacted local water infrastructure.
Contaminants: Combined Radium (-226 and -228).
Contaminants: Combined Radium (-226 and -228).
Key contaminant findings
Based on the most recent EPA sampling data for Denver's water supply.
Well within EPA limits.
Violation history
Denver's water system has 14 total violations on record, including 2 health-based violations. 3 remain unresolved.
Flood & environmental risk
Bremer County has experienced 9 federally declared disasters since 1965. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Cedar River At Waverly, Cedar River At Janesville, Cedar River At Cedar Falls.
Where does Denver's water come from?
Denver's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 2,087 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Cedar River At Waverly (river), Cedar River At Janesville (river), Cedar River At Cedar Falls (river).
What Denver residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Denver'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.
Denver's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Denver
Industrial polluters nearby
Reported releases to surface water by facilities near Denver, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
CMI ROADBUILDING INC. WAVERLY, IA50677 | — | — | 7.2 mi |
MASTERBRAND CABINETS WATERLOO OPERATIONS WATERLOO, IA50703 | — | — | 9.0 mi |
ADVANCED HEAT TREAT CORP. WATERLOO, IA50703 | — | — | 8.9 mi |
ADVANCED HEAT TREAT CORP WATERLOO, IA50703 | — | — | 8.9 mi |
HYDRITE CHEMICAL CO. WATERLOO, IA50703 | — | — | 9.1 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Flood & disaster history
Bremer County has experienced 9 federally declared disasters since 1965. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
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. | 0.6 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Denver compares by contaminant
Explore where Denver ranks among all Iowa cities for specific contaminants.
Water source & infrastructure
Where Denver's water comes from
Denver'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 2,087 people through 2 water systems.
Water bodies near Denver
Denver is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Denver
| System Name | PWSID | Population | Source |
|---|---|---|---|
| DENVER WATER SUPPLY | IA0915030 | 1,919 | GW |
| MEADOW LANE MOBILE HOME PARK | IA0900647 | 168 | GW |
How Denver compares
Full Iowa rankings →Denver's score of 90.5/100 is above the average of 72/100 among major Iowa cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Iowa rankings →About Denver, IA
Wikipedia →Denver is a city in Bremer County in the U.S. state of Iowa. The population was 1,919 at the time of the 2020 census. It is part of the Waterloo–Cedar Falls Metropolitan Statistical Area.
Learn more about your water
Guides and resources related to Denver's water quality findings.
Explore water quality across Bremer
Frequently asked questions
Is Denver, IA tap water safe to drink?
Denver's water quality earned a grade of A (90.5/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #173 out of 436 cities tested in Iowa.
What contaminants are in Denver's water?
Lead was measured at 0.6 ppb (90th percentile). 14 violations are on record.
How is Denver'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 Denver?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Denver's water come from?
Denver's water is sourced from Groundwater. The city has 2 water systems serving approximately 2,087 residents.
What health violations has Denver's water system had?
Denver has 2 health-based violations on record. The most recent violation was recorded in April 2019. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 3 violations remain unresolved.
Is Denver's groundwater at risk of contamination?
Denver 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 14 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 Denver's water compare to other cities?
Denver ranks #173 out of 436 cities in Iowa (better than 60% of state cities) and #2189 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.