Is Allison, 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 ↓
87.5/100
waterverge.com Allison, IA — Water Quality Report
Allison's drinking water received a grade of A- (87.5 out of 100), indicating good water quality. The city's 1 water system serves approximately 966 residents using groundwater.
Lead levels were measured at 7.6 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 4 violations on record, including 0 health-based violations. 1 remains unresolved.
What to know about Allison's water
Allison ranks #290 out of 436 cities in Iowa for water quality, placing it below average in the state.
Allison 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.
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, Allison may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Allison, IA water safe to drink?
Allison's tap water meets most EPA standards but has areas that warrant attention. With a grade of A- (87.5/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 966 residents using groundwater (wells).
Recent water quality updates for Allison
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Allison's water quality assessment. Grade: A- (87.5/100).
Federal disaster declaration (FEMA DR-4421). Flood event — may have impacted local water infrastructure.
Contaminants: Revised Total Coliform Rule.
Federal disaster declaration (FEMA DR-4289). Flood event — may have impacted local water infrastructure.
Contaminants: Coliform (TCR).
Contaminants: Coliform (TCR).
Key contaminant findings
Based on the most recent EPA sampling data for Allison'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
Allison's water system has 4 total violations on record, including 0 health-based violations. 1 remain unresolved.
Flood & environmental risk
Butler County has experienced 10 federally declared disasters since 1969. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.
Where does Allison's water come from?
Allison's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 966 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Allison 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.
Allison'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 Allison
Industrial polluters nearby
Reported releases to surface water by facilities near Allison, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
POET BIOREFINING - SHELL ROCK LLC SHELL ROCK, IA50670 | — | — | 9.0 mi |
SHELL ROCK SOY PROCESSING LLC SHELL ROCK, IA50670 | — | — | 9.0 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Flood & disaster history
Butler County has experienced 10 federally declared disasters since 1969. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Allison'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. | 7.6 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Allison compares by contaminant
Explore where Allison ranks among all Iowa cities for specific contaminants.
Water source & infrastructure
Where Allison's water comes from
Allison'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 966 people through 1 water system.
Water systems serving Allison
| System Name | PWSID | Population | Source |
|---|---|---|---|
| ALLISON WATER SUPPLY | IA1203026 | 966 | GW |
How Allison compares
Full Iowa rankings →Allison's score of 87.5/100 is above the average of 72/100 among major Iowa cities. It outscores 9 of 10 nearby cities.
Nearby cities
View Iowa rankings →About Allison, IA
Wikipedia →Allison is a city in, and the county seat of, Butler County, Iowa, United States. The population was 966 at the 2020 census. Allison is home to the Butler County Fair. The city was named for U.S. Senator William B. Allison in 1881.
Learn more about your water
Guides and resources related to Allison's water quality findings.
Explore water quality across Butler
Frequently asked questions
Is Allison, IA tap water safe to drink?
Allison's water quality earned a grade of A- (87.5/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #290 out of 436 cities tested in Iowa.
What contaminants are in Allison's water?
Lead was measured at 7.6 ppb (90th percentile). 4 violations are on record.
How is Allison'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 Allison?
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 Allison's water come from?
Allison's water is sourced from Groundwater. The city has 1 water system serving approximately 966 residents.
Is Allison's groundwater at risk of contamination?
Allison 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 4 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 Allison's water compare to other cities?
Allison ranks #290 out of 436 cities in Iowa (better than 33% of state cities) and #4037 out of 15744 cities nationally (74th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Allison's small water system affect quality?
Allison's system serves approximately 966 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 4 violations on record.