D Hanis, TX vs Houston, TX

When comparing tap water quality between D Hanis, TX and Houston, TX, Houston currently holds a substantial 22-point lead in average WaterQ score, with a score of 95 out of 100 versus 73 for D Hanis. D Hanis, TX carries a C grade while Houston, TX 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.

Houston, TX is the larger of the two, with 5.9 million more residents than D Hanis. Houston is served by 525 public water systems, compared with 1 in D Hanis — a difference of 524 systems. 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 D Hanis or Houston, 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 D Hanis or Houston 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.