PFAS ("forever chemicals") · 2025

Perfluorohexanoic acid in Ontario Municipal Utilities Company, CA tap water

Detected — no federal limit

Ontario Municipal Utilities Company, CA's 2025 report shows Perfluorohexanoic acid detected, but the EPA has not set an enforceable federal limit for it.

The measurement

StatisticValue
Highest single sample
Source water
5.6 NG/L
Average
Source water
1.3647058823529412 NG/L

Verbatim from Ontario Municipal Utilities Company, CA's 2025 Consumer Confidence Report — source document ↗

About Perfluorohexanoic acid

Perfluorohexanoic acid, a shorter-chain PFAS 'forever chemical.'

Monitored under EPA rules; persistent and widely detected.

How Ontario Municipal Utilities Company, CA compares

5 of the 229 systems measuring Perfluorohexanoic acid on The Water Map have it at or above the federal limit:

Nearby systems also reporting Perfluorohexanoic acid:

People also ask

+Is there Perfluorohexanoic acid in Ontario Municipal Utilities Company, CA tap water?

Yes — Ontario Municipal Utilities Company, CA's 2025 Consumer Confidence Report lists Perfluorohexanoic acid at 1.3647058823529412 NG/L. Ontario Municipal Utilities Company, CA's 2025 report shows Perfluorohexanoic acid detected, but the EPA has not set an enforceable federal limit for it.

+What's the federal limit for Perfluorohexanoic acid in drinking water?

The EPA has not set an enforceable federal limit for Perfluorohexanoic acid. Utilities still report any measured levels in their annual Consumer Confidence Report.

+What is Perfluorohexanoic acid?

Perfluorohexanoic acid, a shorter-chain PFAS 'forever chemical.' Monitored under EPA rules; persistent and widely detected.

+Which other U.S. cities have Perfluorohexanoic acid over the federal limit?

5 of the 229 systems on The Water Map measuring Perfluorohexanoic acid report it at or above the federal limit. Examples include Boonsboro Keedysville, MD, City of Poquoson, VA, Hampton, VA.

+Where does this Perfluorohexanoic acid measurement come from?

This page reproduces the Perfluorohexanoic acid entry from the 2025 Consumer Confidence Report published by the Ontario Municipal Utilities Company, CA water utility — the annual drinking-water report every U.S. utility is required by federal law to publish. The original source document is archived at /water/ca/ontario-municipal-utilities-company/2025/source.

Full report
All Ontario Municipal Utilities Company, CA water-quality data →
Every contaminant measured in the 2025 report.
Contaminant pillar
Perfluorohexanoic acid across the U.S. →
Every public water system measuring Perfluorohexanoic acid, ranked.