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
51–75 of 498Keokuk Municipal Water Works
IA5640019 · 9,900 served
Fairfield Water Supply
IA5131033 · 9,821 served
Mahaska Rural Water System, Inc.
IA6273901 · 9,818 served
Grinnell Water Department
IA7930008 · 9,564 served
Bondurant Muni Water Supply
IA7717032 · 9,393 served
Denison Water Supply
IA2424027 · 9,381 served
Mount Pleasant Municipal Utilities
IA4453016 · 9,274 served
Iowa Lakes Regional Water - Osgood
IA3060001 · 9,021 served
Knoxville Water Works
IA6342036 · 8,400 served
Rathbun Reg Wtr Assn (burlington)
IA0400902 · 8,375 served
Sioux Center Municipal Water Department
IA8486053 · 8,231 served
Perry Municipal Water Works
IA2561036 · 7,836 served
Webster City Water Supply
IA4063094 · 7,825 served
Clear Lake Water Department
IA1716076 · 7,687 served
Decorah Water Department
IA9630012 · 7,615 served
Southeast Polk Rwd
IA7774701 · 7,565 served
Creston Water Supply
IA8816089 · 7,536 served
Charles City Water Supply
IA3405012 · 7,446 served
Washington Water Department
IA9271068 · 7,362 served
Atlantic Municipal Utilities
IA1509074 · 7,252 served
Hiawatha Water Dept
IA5735045 · 7,183 served
Osceola Rural Water System-north
IA7227701 · 7,002 served
Nevada Water Supply
IA8562044 · 6,925 served
Iowa Lakes Regional Water
IA2100701 · 6,755 served
Eldridge Water Supply
IA8230008 · 6,726 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