Is Janesville, IA 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 ↓
91.7/100
waterverge.com Janesville, IA — Water Quality Report
Janesville's drinking water received a grade of A (91.7 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 1,034 residents using purchased ground water.
Lead levels were measured at 5.4 ppb (90th percentile), which is within EPA limits but above recommended levels. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 12 violations on record, including 5 health-based violations. 1 remains unresolved.
What to know about Janesville's water
Janesville ranks #115 out of 436 cities in Iowa for water quality, placing it mid-range in the state.
Janesville purchases its water from a regional wholesaler, meaning quality depends on both the supplier's treatment and the local distribution system's condition.
While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection.
As a small community water system, Janesville may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Janesville, IA water safe to drink?
Janesville's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (91.7/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 1,034 residents using groundwater (wells).
Recent water quality updates for Janesville
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Janesville's water quality assessment. Grade: A (91.7/100).
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: Nitrate, Coliform (TCR).
Contaminants: Arsenic.
Contaminants: Combined Radium (-226 and -228).
Key contaminant findings
Based on the most recent EPA sampling data for Janesville's water supply.
Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb. An NSF 53-certified filter provides additional protection.
Violation history
Janesville's water system has 12 total violations on record, including 5 health-based violations. 1 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, West Fork Cedar River At Finchford, Shell Rock River At Shell Rock, Cedar River At Cedar Falls.
Where does Janesville's water come from?
Janesville's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,034 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), West Fork Cedar River At Finchford (river), Shell Rock River At Shell Rock (river), Cedar River At Cedar Falls (river).
What Janesville 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.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
Janesville'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 Janesville
Industrial polluters nearby
Reported releases to surface water by facilities near Janesville, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
ZINPRO CORP SHELL ROCK, IA50670 | — | — | 8.1 mi |
FELDMEIER EQUIPMENT INC SHELL ROCK, IA50670 | — | — | 7.7 mi |
UNVERFERTH MANUFACTURING CO INC BRENT DIV SHELL ROCK, IA50670 | — | — | 9.2 mi |
CMI ROADBUILDING INC. WAVERLY, IA50677 | — | — | 5.4 mi |
SHELL ROCK SOY PROCESSING LLC SHELL ROCK, IA50670 | — | — | 10.0 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.
Recommended water filters
Based on contaminants detected in Janesville'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. | 5.4 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Janesville compares by contaminant
Explore where Janesville ranks among all Iowa cities for specific contaminants.
Water source & infrastructure
Where Janesville's water comes from
Janesville 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 Janesville'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 local government ownership and serves approximately 1,034 people through 1 water system.
Water bodies near Janesville
Janesville is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Janesville
| System Name | PWSID | Population | Source |
|---|---|---|---|
| JANESVILLE WATER SUPPLY | IA0932001 | 1,034 | GWP |
How Janesville compares
Full Iowa rankings →Janesville's score of 91.7/100 is above the average of 72/100 among major Iowa cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Iowa rankings →About Janesville, IA
Wikipedia →Janesville is a city in Black Hawk and Bremer counties in the U.S. state of Iowa. The population was 1,034 at the 2020 census. It is part of the Waterloo–Cedar Falls Metropolitan Statistical Area.
Learn more about your water
Guides and resources related to Janesville's water quality findings.
Explore water quality across Bremer
Frequently asked questions
Is Janesville, IA tap water safe to drink?
Janesville's water quality earned a grade of A (91.7/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #115 out of 436 cities tested in Iowa.
What contaminants are in Janesville's water?
Lead was measured at 5.4 ppb (90th percentile). 12 violations are on record.
How is Janesville'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 Janesville?
While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Janesville's water come from?
Janesville's water is sourced from Purchased ground water. The city has 1 water system serving approximately 1,034 residents.
What health violations has Janesville's water system had?
Janesville has 5 health-based violations on record. The most recent violation was recorded in November 2010. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 1 violation remains unresolved.
Is Janesville's groundwater at risk of contamination?
Janesville 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 12 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 Janesville's water compare to other cities?
Janesville ranks #115 out of 436 cities in Iowa (better than 74% of state cities) and #1547 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 Janesville's small water system affect quality?
Janesville's system serves approximately 1,034 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 12 violations on record.