Iowa Water Quality Report

Tap water quality data for 4 cities in Iowa, updated 2026.

Avg. Hardness: 240 ppm (Very Hard)3 cities with violationsAll cities below EPA lead limit
Avg. Hardness
240 ppm
Very Hard

US average: 100 ppm

Violations (3yr)
88
13 health-based

1 of 4 cities violation-free

Lead Compliance
100%
Below EPA Limit

4 cities tested

Water Source
Surface Water
25% of systems

4 water systems tracked

Water Hardness Across Iowa

Soft
0 (0%)
Moderate
0 (0%)
Hard
1 (33%)
Very Hard
2 (67%)
Hardest: Iowa City (275 ppm)Softest: Davenport (170 ppm)

Not sure what your hardness means? Use our Water Hardness Calculator or find the best hardness test kits.

Iowa Tap Water: What You Need to Know

Iowa has 4 tracked water utilities serving approximately 643K residents. The average water hardness is 240 ppm (14 GPG), classified as Very Hardabove the national average of 100 ppm. Hardness ranges from 170 ppm in Davenport to 275 ppm in Iowa City.

In the past 3 years, 3 of 4 cities in Iowa have recorded water quality violations, totaling 88 violations (13 health-based). All 4 tested cities have lead levels below the EPA action level of 15 ppb.

With very hard water on average, many Iowa residents may notice mineral buildup on fixtures, dry skin, or stiff-feeling hair. A shower filter for hard water can help reduce chlorine exposure, while a water softener addresses the mineral buildup directly.

Frequently Asked Questions About Iowa Water

Is tap water safe to drink in Iowa?

Most tap water in Iowa meets EPA standards, but 3 cities have recorded violations in the past 3 years (13 health-based). We recommend checking your specific city's report on TapWater.org and considering a home water test.

How hard is the water in Iowa?

Iowa's average water hardness is 240 ppm (14 GPG), classified as Very Hard. This is above the national average of 100 ppm. Hardness varies significantly by city — use our Water Hardness Calculator to check your specific area.

Which city in Iowa has the cleanest tap water?

Based on EPA violation data, lead testing, and water quality metrics, Des Moines ranks as having the cleanest tap water in Iowa. It has zero violations in the past 3 years and lead levels well below the EPA action level.

Which city in Iowa has the most water quality issues?

Iowa City currently has the most water quality concerns in Iowa, with 71 violations in the past 3 years. Residents should check their city's detailed water quality report and consider using a certified water filter.

Where does Iowa get its water from?

The majority of Iowa's water systems (25%) use surface water as their primary source. Surface water comes from rivers, lakes, and reservoirs. Each city's specific source can vary — check individual city reports for details.