Physical & aggregate · 2025
Hardness in City of Fairfield, CA tap water
City of Fairfield, CA's 2025 report shows Hardness detected, but the EPA has not set an enforceable federal limit for it.
The measurement
| Statistic | Value | Federal limit |
|---|---|---|
Highest single sample Entry point | 197 MG/L | None set |
Average Source water | 165.58333333333334 MG/L | None set |
Average Entry point | 171.25 MG/L | None set |
Highest single sample Source water | 199 MG/L | None set |
Verbatim from City of Fairfield, CA's 2025 Consumer Confidence Report — source document ↗
About Hardness
A measure of dissolved calcium and magnesium minerals.
Not federally regulated for health; affects scaling, soap use, and taste.
How City of Fairfield, CA compares
Nearby systems also reporting Hardness:
People also ask
+Is there Hardness in City of Fairfield, CA tap water?
Yes — City of Fairfield, CA's 2025 Consumer Confidence Report lists Hardness at 171.25 MG/L. City of Fairfield, CA's 2025 report shows Hardness detected, but the EPA has not set an enforceable federal limit for it.
+What's the federal limit for Hardness in drinking water?
The EPA has not set an enforceable federal limit for Hardness. Utilities still report any measured levels in their annual Consumer Confidence Report.
+What is Hardness?
A measure of dissolved calcium and magnesium minerals. Not federally regulated for health; affects scaling, soap use, and taste.
+Where does this Hardness measurement come from?
This page reproduces the Hardness entry from the 2025 Consumer Confidence Report published by the City of Fairfield, 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/fairfield/2025/source.