Water Quality in Ontario, CA
18 water systems serving 191,456 people
City Overview
Average lead detection across Ontario water systems is 2.2 ppb (Low). The EPA action level is 15 ppb.
Violation Summary
| Total violations on record | 218 |
| Health-based violations | 48 |
| Lead action level violations | 0 |
| Open (unresolved) violations | 0 |
Water Systems in Ontario
Frequently Asked Questions
Is Ontario tap water safe to drink?
Ontario tap water meets EPA standards for most contaminants. Review the individual water system pages below for the latest lead sample results and violation history.
What is the water quality in Ontario, California?
Ontario has 18 public water systems serving approximately 191,456 people. The average lead level across sampled systems is 2.2 ppb. There are 218 total violations on record.
Does Ontario have lead in the water?
EPA monitoring data shows an average lead detection of 2.2 ppb across Ontario's water systems. The EPA action level is 15 ppb. No lead action level violations are currently reported.
How many water utilities serve Ontario?
18 public water systems are registered in Ontario, California with the EPA Safe Drinking Water Information System. Together they serve approximately 191,456 people.