Safest Drinking Water in Ohio 2026
Ohio has 5 public water systems serving 3,648,160 people. The safest system is Cincinnati Public Water System in Cincinnati with a score of 100/100.
Top 5 Water Systems in Ohio
| # | Water System | City | Pop. Served | Source | Violations | Score |
|---|---|---|---|---|---|---|
| 1 | Cincinnati Public Water System | Cincinnati | 750,200 | Surface water | 0 | A (100) |
| 2 | Del-Co Water Company, INC. | Delaware | 150,000 | Surface water | 0 | A (100) |
| 3 | Cleveland Public Water System | Cleveland | 1,308,955 | Surface water | 0 | C (72) |
| 4 | Clermont Public Water System | Batavia | 133,059 | Surface water | 2 | F (45) |
| 5 | Columbus Public Water System | Columbus | 1,305,946 | Surface water | 3 | F (40) |
Water quality data for Ohio is sourced from the EPA Safe Drinking Water Information System (SDWIS), which tracks compliance for all public water systems.
Frequently Asked Questions
Cincinnati Public Water System in Cincinnati has the highest Water Safety Score in Ohio at 100/100 (Grade A), serving 750,200 people.
Ohio has 5 public water systems serving 3,648,160 people. The average Water Safety Score is 71/100.
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%).