State Hub
Iowa Water Quality
498
Utilities in database
2.9M
Residents served
35%
On private wells
2
Key contaminants tracked
Drinking Water in Iowa
Iowa has 498 community water systems serving approximately 2.9 million residents. Primary water sources include groundwater. The most commonly reported contaminants include disinfection byproducts, arsenic. 35% of Iowa residents rely on private wells. DNR holds primary enforcement authority under the Safe Drinking Water Act.
Utilities in Iowa
1–25 of 498Des Moines Water Works
IA7727031 · 246,055 served
Iowa-american Wtr Co-davenport
IA8222001 · 147,720 served
Cedar Rapids Water Department
IA5715093 · 142,364 served
Sioux City Water Supply
IA9778054 · 85,791 served
City of Ankeny
IA7709053 · 76,207 served
West Des Moines Water Works
IA7785007 · 73,959 served
Waterloo Water Works
IA0790074 · 69,504 served
Iowa City Water Department
IA5225079 · 68,753 served
Council Bluffs Water Works
IA7820080 · 64,447 served
Dubuque Water Works
IA3126052 · 59,667 served
Ames Water Treatment Plant
IA8503039 · 55,177 served
Urbandale Water Utility
IA7780042 · 45,605 served
Isu
IA8503528 · 42,000 served
Marion Municipal Water Dept
IA5751035 · 41,623 served
Cedar Falls Municipal Water Utilities
IA0709084 · 40,713 served
Ia Regional Utilities Assoc (waverly)
IA0990701 · 37,820 served
Rathbun Regional Water Assn (rathbun)
IA0400900 · 33,000 served
Waukee Water Supply
IA2573080 · 31,823 served
Marshalltown Water Works
IA6469042 · 27,591 served
Mason City Water Department
IA1750048 · 27,338 served
University Water System
IA5225101 · 26,684 served
Burlington Municipal Waterworks
IA2909053 · 26,015 served
Fort Dodge Water Supply
IA9433050 · 25,874 served
Ottumwa Water Works
IA9083012 · 25,529 served
Muscatine Power & Water
IA7048001 · 25,516 served
Key Contaminant Concerns in Iowa
DBPs
When utilities add chlorine to water to kill pathogens, it reacts with dissolved organic matter — leaves, algae, soil — to produce disinfection byproducts (DBPs). Over 600 DBPs have been identified. The EPA regulates two groups: total trihalomethanes (TTHMs, including chloroform) and haloacetic acids (HAA5). DBP levels tend to be highest in surface water systems and in warm months when organic matter is elevated.
Arsenic
Arsenic (As) occurs naturally in rock and soil, dissolving into groundwater through natural weathering processes. Inorganic arsenic — the form found in drinking water — is a known human carcinogen. The western United States has particularly arsenic-rich geological formations, but elevated levels have been found in 48 states. Arsenic is tasteless and odorless.
Iowa Water FAQs
Quick Links
Data source: Utility data from EPA SDWIS. 498 active community water systems ingested. CCR contaminant data ingestion in progress.
Last updated: 2026-04-22