ONTARIO MUNICIPAL UTILITIES COMPANY
Ontario, CA · 185,010 served
ONTARIO MUNICIPAL UTILITIES COMPANY serves 185,010 people in Ontario, CA. It has 0 health-based violations in the last 5 years. TapGraded gives this system a B.
Score breakdown
Health-based violations (5y)
0
Monitoring violations (5y)
0
Currently unaddressed
0
Overall score
80/100
Violation history (last 5 years)
No violations on record.
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Lead (Lead and Copper Rule)
EPA's current lead action level is 15 ppb (dropping to 10 ppb in 2027 under the Lead and Copper Rule Improvements).
Latest EPA Lead and Copper Rule 90th-percentile reading (monitoring period ending December 31, 2024).
PFAS (UCMR5 occurrence data)
System details
- System type
- Community water system
- Water source
- Surface water purchased from another system
- Ownership
- Local government
- Service connections
- 39,996
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Is Ontario, CA tap water safe to drink?
ONTARIO MUNICIPAL UTILITIES COMPANY has 0 health-based violations in the last 5 years. TapGraded gives this system a B. A Tap Grade summarizes public EPA compliance records; it is not a determination that water is safe or unsafe to drink.
Does ONTARIO MUNICIPAL UTILITIES COMPANY have lead in its water?
The most recent 90th-percentile lead sample is 0.6 ppb, versus the EPA action level of 15 ppb.
Has PFAS been detected in ONTARIO MUNICIPAL UTILITIES COMPANY's water?
Yes — PFAS was detected at or above the EPA MCL for 2 of the tracked analytes.
Source: EPA SDWIS/ECHO · Data as of 2026Q2
TapGraded presents public EPA data for information only — it is not health advice and not a determination that any water is safe or unsafe to drink. For health concerns, contact your water utility or local health department.