Metals · 2026
Iron in Contra Costa Water District, CA tap water
Contra Costa Water District, CA's 2026 Consumer Confidence Report shows Iron at or above the federal limit (300 UG/L MCL). Measured value is 3.0× the threshold.
The measurement
| Statistic | Value | Federal limit |
|---|---|---|
Average Source water | 899 UG/L | 300 UG/L MCL |
Highest single sample Source water | 899 UG/L | 300 UG/L MCL |
Verbatim from Contra Costa Water District, CA's 2026 Consumer Confidence Report — source document ↗
About Iron
A naturally occurring metal common in groundwater.
Regulated only as a secondary (cosmetic) standard; causes rusty color, staining, and metallic taste.
How Contra Costa Water District, CA compares
5 of the 236 systems measuring Iron on The Water Map have it at or above the federal limit:
Nearby systems also reporting Iron:
People also ask
+Is there Iron in Contra Costa Water District, CA tap water?
Yes — Contra Costa Water District, CA's 2026 Consumer Confidence Report lists Iron at 899 UG/L. Contra Costa Water District, CA's 2026 Consumer Confidence Report shows Iron at or above the federal limit (300 UG/L MCL). Measured value is 3.0× the threshold.
+What's the federal limit for Iron in drinking water?
The federal MCL for Iron is 300 UG/L. The EPA enforces this against the regulated reporting statistic (running annual average or 90th percentile), not a single-sample spike.
+What is Iron?
A naturally occurring metal common in groundwater. Regulated only as a secondary (cosmetic) standard; causes rusty color, staining, and metallic taste.
+Which other U.S. cities have Iron over the federal limit?
5 of the 236 systems on The Water Map measuring Iron report it at or above the federal limit. Examples include Bakersfield, City of, CA, City of San Jose - Evg/edv/coy, CA, City of Vallejo, CA.
+Where does this Iron measurement come from?
This page reproduces the Iron entry from the 2026 Consumer Confidence Report published by the Contra Costa Water District, 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/contra-costa-water-district/2026/source.