Iowa Water Systems
1,077 community water systems in Iowa, ranked by violation count. Data from EPA Safe Drinking Water Information System (SDWIS).
Iowa operates 1,077 community water systems regulated by the EPA Safe Drinking Water Information System (SDWIS) under the Safe Drinking Water Act. Together these utilities serve an estimated 3,003,953 residents, each filing compliance results with the state's primacy agency and, for federally listed contaminants, with the U.S. Environmental Protection Agency.
Across the state, SDWIS records contain 729 total violations, of which 121 systems carry at least one active health-based violation, a Maximum Contaminant Level (MCL) exceedance or treatment-technique failure. That represents roughly 11% of Iowa systems.
Violation counts reflect both infrastructure realities and reporting diligence, a state with more small rural systems will accumulate more monitoring-type violations without necessarily delivering worse water. Health-based violations are the stronger safety signal. A past violation does not itself indicate current unsafe water; utilities must notify customers, remediate, and publish an annual Consumer Confidence Report. All numbers below draw directly from the federal SDWIS record.
Which water systems have violations? (63)
Systems with No Violations (437)
437 water systems in Iowa have zero recorded violations. Showing the 50 largest by population served.
All Water Systems in Iowa (1,077)
Page 19 of 22, ordered by population served.
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About This Data
Water system data is from the EPA Safe Drinking Water Information System (SDWIS). Health-based violations include Maximum Contaminant Level (MCL) and Treatment Technique (TT) violations that may pose a direct risk to public health. Only community water systems (CWS) are included.
Source: U.S. Environmental Protection Agency, SDWIS Federal Reporting Services U.S. Environmental Protection Agency, SDWIS Federal Reporting Services
Read our methodology - how this data is sourced, computed, and verified.