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
26–50 of 498Iowa-american Wtr Co-clinton District
IA2326048 · 24,769 served
Johnston Municipal Water Supply
IA7740011 · 24,064 served
Coralville Muni Water System
IA5208071 · 22,318 served
Sirwa #2 (creston)
IA8080701 · 20,793 served
North Liberty Water Supply
IA5252072 · 20,491 served
Warren Water District
IA9133701 · 20,095 served
Altoona Water Supply
IA7707030 · 19,565 served
Clive Water Department
IA7720051 · 19,010 served
Wapello Rural Water Assoc.
IA9000742 · 17,263 served
Newton Water Supply
IA5059064 · 16,518 served
Indianola Water Supply
IA9133075 · 15,833 served
Grimes Water Supply
IA7736011 · 15,392 served
Norwalk Water Supply
IA9164078 · 14,334 served
Poweshiek Water Association
IA8670701 · 13,920 served
Xenia Rwd (des Moines)
IA2573701 · 12,860 served
Oskaloosa Municipal Water Dept
IA6273005 · 12,808 served
Boone Water Works
IA0819033 · 12,704 served
Rathbun Reg Water Assn (ft Madison)
IA0400901 · 11,840 served
Storm Lake Water Treatment Plant
IA1178097 · 11,431 served
Spencer Municipal Water Utility
IA2171071 · 11,325 served
Ft Madison Muni Water Works
IA5625062 · 11,087 served
Pella Water Works Department
IA6368033 · 11,052 served
Lemars Water Department
IA7540174 · 10,606 served
Waverly Water Department
IA0990085 · 10,394 served
Carroll Municipal Water Supply
IA1415072 · 10,184 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