What's in City of Hayward, CA tap water

The 2026 Consumer Confidence Report for the City of Hayward, CA water utility lists 1 contaminant at or above the federal limit: Manganese. Whether that means the water is "unsafe" depends on which contaminant, how long the exposure, and individual health factors. The table on this page shows the measured value, the federal threshold, and the regulated statistic used for compliance.

93 contaminants were measured in City of Hayward, CA's 2026 Consumer Confidence Report, spanning other, metals, and vocs & pesticides. 77 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.

One contaminant in City of Hayward, CA's 2026 report sits at or above the federal limit: Manganese (4.3× the limit). The EPA enforces these limits against the regulated reporting statistic — typically a running annual average or 90th percentile — not a one-off sample spike.

The contaminant with the highest measured value relative to its federal limit in the 2026 report is Manganese, at 4.3× the federal threshold. It belongs to the metals family of contaminants.

Every value is transcribed from City of Hayward, CA's 2026 Consumer Confidence Report — the annual drinking-water report every U.S. public water utility is required by federal law to publish. The original source document is archived and viewable on this site. A water-quality report covers an entire service area, not a single address.

Each U.S. public water utility publishes one Consumer Confidence Report per year, covering the prior calendar year's measurements. This page reflects the 2026 report; a new report will replace it once the utility publishes its next annual update.