Safest Drinking Water in Arizona 2026
Arizona has 5 public water systems serving 3,388,834 people. The safest system is Tucson City Of in Tucson with a score of 80/100.
Top 5 Water Systems in Arizona
| # | Water System | City | Pop. Served | Source | Violations | Score |
|---|---|---|---|---|---|---|
| 1 | Tucson City Of | Tucson | 732,906 | Ground water | 0 | B (80) |
| 2 | Mesa City Of | Mesa | 466,000 | Surface water | 0 | C (75) |
| 3 | Chandler City Of | Chandler | 247,328 | Surface water | 1 | D (64) |
| 4 | Phoenix City Of | Phoenix | 1,695,000 | Surface water | 2 | D (60) |
| 5 | Gilbert, Town Of | Gilbert | 247,600 | Surface water | 3 | F (33) |
Water quality data for Arizona is sourced from the EPA Safe Drinking Water Information System (SDWIS), which tracks compliance for all public water systems.
Frequently Asked Questions
Tucson City Of in Tucson has the highest Water Safety Score in Arizona at 80/100 (Grade B), serving 732,906 people.
Arizona has 5 public water systems serving 3,388,834 people. The average Water Safety Score is 62/100.
The Water Safety Score (0-100) is based on health violations (40%), contaminant exceedances (30%), enforcement history (20%), and monitoring violations (10%). Higher scores mean cleaner, safer water.
Water Safety Score: health violations (40%), contaminant exceedances (30%), enforcement history (20%), monitoring violations (10%).
The this entity category groups every U.S. public drinking-water safety entity sharing this attribute. The list above is the data; the paragraphs below explain what the grouping means against the broader the EPA Safe Drinking Water Information System (SDWIS) distribution and how to read the relative rankings within the category.
For readers using this category as a starting point, the per-entity detail pages linked from the table above carry the underlying the EPA Safe Drinking Water Information System (SDWIS) data in full. The category-level view is the filter; the per-entity pages are the actual answer.
Source: EPA Ground Water and Drinking Water, 2026.