Mason City, IA vs Des Moines, IA
Which City Has Better Water Quality?
Mason City, IA and Des Moines, IA currently share an identical average WaterQ score, each scoring 76 out of 100. Both cities currently carry a B grade overall. Because a WaterQ score is an aggregate across all public water systems serving a city, near-identical scores can still mask differences at the system level, so residents of either city should review their specific water system's record for the most relevant detail.
Des Moines, IA is the larger of the two, with 226,282 more residents than Mason City. Des Moines is served by 2 public water systems, compared with 1 in Mason City — a difference of 1 system. A larger number of systems often reflects a more fragmented distribution network spanning multiple utilities, suburbs, or rural service areas, while a single large utility serving a big population can benefit from economies of scale in treatment and monitoring, but may also face more complex, aging infrastructure to maintain.
For residents of either Mason City or Des Moines, the most useful next step is to look up the specific water system that serves your address, since city-wide averages combine results from every system in the area. Visit the Mason City or Des Moines city pages below for a breakdown of local systems, recent violations, and contaminant-specific data, or browse WaterQ's contaminants directory to learn what each measured substance means for health.
Detailed Comparison
| Metric | Mason City | Des Moines |
|---|---|---|
| Water Quality Score | 76 | 76 |
| Grade | B | B |
| Water Systems | 1 | 2 |
| Population | 27,338 | 253,620 |
| County | ||
| State | IA | IA |
Analysis
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Frequently asked questions
Which city has better tap water quality: Mason City or Des Moines?
Mason City and Des Moines currently have similar overall WaterQ scores. Review each city page for recent test and violation details.
How are Mason City and Des Moines water scores calculated?
WaterQ scores are based on EPA-reported drinking water data, including contaminant detections, violations, and compliance records across local systems.
Where can I view full reports for Mason City and Des Moines?
Use the city detail pages to see water systems, score breakdowns, and trend context for Mason City, IA and Des Moines, IA.