Safest Drinking Water in Colorado 2026
Colorado has 5 public water systems serving 2,713,061 people. The safest system is Aurora City Of in Aurora with a score of 88/100.
Top 5 Water Systems in Colorado
| # | Water System | City | Pop. Served | Source | Violations | Score |
|---|---|---|---|---|---|---|
| 1 | Aurora City Of | Aurora | 533,407 | Surface water | 0 | B (88) |
| 2 | Colorado Springs Utilities | Colorado Springs | 464,111 | Surface water | 0 | B (85) |
| 3 | Westminster City Of | Westminster | 202,078 | Surface water | 0 | B (80) |
| 4 | Denver Water Board | Denver | 1,287,000 | Surface water | 0 | C (72) |
| 5 | Thornton City Of | Thornton | 226,465 | Surface water | 0 | C (70) |
Water quality data for Colorado is sourced from the EPA Safe Drinking Water Information System (SDWIS), which tracks compliance for all public water systems.
Frequently Asked Questions
Aurora City Of in Aurora has the highest Water Safety Score in Colorado at 88/100 (Grade B), serving 533,407 people.
Colorado has 5 public water systems serving 2,713,061 people. The average Water Safety Score is 79/100.
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.