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
151–175 of 498Clarion Water Supply
IA9909031 · 2,810 served
Grundy Center Water Supply
IA3833013 · 2,796 served
Hawarden Water Supply
IA8434040 · 2,700 served
Missouri Valley Water Supply
IA4344088 · 2,684 served
Bloomfield Muni Water Dept
IA2613019 · 2,682 served
Eldora Water Supply
IA4236005 · 2,664 served
Kalona Water Dept
IA9233012 · 2,630 served
Rock Rapids Municipal Water Works
IA6065092 · 2,611 served
Sirwa - Corning
IA0207704 · 2,585 served
Center Point Water Supply
IA5718006 · 2,579 served
Hudson Water Supply
IA0737062 · 2,546 served
West Union Water Supply
IA3383014 · 2,540 served
Mitchellville Water Supply
IA7751092 · 2,515 served
Postville Water Department
IA0375053 · 2,513 served
West Branch Water Works
IA1694000 · 2,509 served
Jesup Municipal Water Supply
IA1044006 · 2,508 served
Poweshiek Water Association (iac)
IA4868701 · 2,490 served
Belmond Water Supply
IA9905003 · 2,463 served
Marengo Water Supply
IA4843033 · 2,435 served
W Central Rwa - Denison Subsys
IA2424701 · 2,428 served
Ogden Municipal Utilities
IA0858090 · 2,419 served
Toledo Water Supply
IA8676027 · 2,399 served
Park View Water & Sanitary District
IA8200855 · 2,389 served
Cascade Municipal Water Supply
IA3118080 · 2,386 served
Hull Water Supply
IA8444063 · 2,384 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