Metals · 2025
Calcium in City of Cupertino, CA tap water
City of Cupertino, CA's 2025 report shows Calcium detected, but the EPA has not set an enforceable federal limit for it.
The measurement
| Statistic | Value | Federal limit |
|---|---|---|
Highest single sample Source water | 96 MG/L | None set |
Average Source water | 46.75 MG/L | None set |
Verbatim from City of Cupertino, CA's 2025 Consumer Confidence Report — source document ↗
About Calcium
A naturally occurring mineral that contributes to water hardness.
Not federally regulated for health; affects scaling and taste.
How City of Cupertino, CA compares
Nearby systems also reporting Calcium:
People also ask
+Is there Calcium in City of Cupertino, CA tap water?
Yes — City of Cupertino, CA's 2025 Consumer Confidence Report lists Calcium at 46.75 MG/L. City of Cupertino, CA's 2025 report shows Calcium detected, but the EPA has not set an enforceable federal limit for it.
+What's the federal limit for Calcium in drinking water?
The EPA has not set an enforceable federal limit for Calcium. Utilities still report any measured levels in their annual Consumer Confidence Report.
+What is Calcium?
A naturally occurring mineral that contributes to water hardness. Not federally regulated for health; affects scaling and taste.
+Where does this Calcium measurement come from?
This page reproduces the Calcium entry from the 2025 Consumer Confidence Report published by the City of Cupertino, 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/cupertino/2025/source.