Ontario, California Water Quality Report
Water quality data for 4 water systems serving 185,210 people.
Water Source
Detected Contaminants
| Contaminant | Detected Level | EPA Limit (MCL) | Health Guideline | % of Limit | Status |
|---|---|---|---|---|---|
| PFBA | 0.006 | No federal limit | 1000.0 ug/L(EWG) | 0% | Below guideline |
| PFHxA | 0.007 | No federal limit | 1000.0 ug/L(EWG) | 0% | Below guideline |
| PFHxS | 0.004 | 0.010 ug/L | 0.001 ug/L(EWG) | 42% | Within limit |
| PFOA | 0.030 | 0.004 ug/L | 0.090 ug/L(EWG) | 750% | Above limit |
| PFOS | 0.005 | 0.004 ug/L | 0.300 ug/L(EWG) | 130% | Above limit |
| PFPeA | 0.007 | No federal limit | 1000.0 ug/L(EWG) | 0% | Below guideline |
Recommended Water Filters
Based on the contaminants detected in your water supply, these filtration systems are recommended:
Reverse Osmosis (RO)
Reverse osmosis systems remove up to 99% of PFAS compounds. Recommended for homes with detected PFAS.
Up to 99% PFAS removal
Get a Free Water Quality Consultation
Connect with a certified water treatment professional in Ontario, California.
Get Water Quality Alerts
Be the first to know when water quality changes in Ontario.
Compliance & Violations
Active Violations (8)
71
Jul 1, 2007
71
Jul 1, 2004
51
Nov 14, 2001
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Violation
Unknown
Resolved Violations (39)
71
Jul 1, 2004
71
Jul 1, 2004
71
Jul 1, 2004
71
Jul 1, 2004
71
Jul 1, 2004
+ 34 more resolved violations
Frequently Asked Questions
Is Ontario tap water safe to drink?
Ontario's water has 2 contaminants detected above EPA limits. While the water is treated, residents may want to consider additional filtration.
What contaminants are in Ontario tap water?
6 contaminants have been detected in Ontario's water supply across 4 water systems. See the full contaminant table above for details.
How can I improve my water quality in Ontario?
Install a water filter rated for the specific contaminants found in Ontario's water. See our filter recommendations above. You can also request your utility's Consumer Confidence Report for the most current test results.
Does Ontario have any water quality violations?
Yes, Ontario currently has 8 active violations. See the violations section above for details.