Green Bay, WI vs Milwaukee, WI

When comparing tap water quality between Green Bay, WI and Milwaukee, WI, Milwaukee currently holds a substantial 44-point lead in average WaterQ score, with a score of 95 out of 100 versus 51 for Green Bay. Green Bay, WI carries a D grade while Milwaukee, WI carries an A. A WaterQ score reflects an aggregate of EPA-reported violations, monitoring data, and compliance history across all public water systems serving each city, so a higher score generally indicates fewer recent violations and a stronger compliance record, though it does not guarantee that every tap in the city tests identically.

Milwaukee, WI is the larger of the two, with 519,462 more residents than Green Bay. Milwaukee is served by 5 public water systems, compared with 4 in Green Bay — 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 Green Bay or Milwaukee, 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 Green Bay or Milwaukee 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.