How do I find out what's in my tap water?

Community water systems must deliver a Consumer Confidence Report by July 1 each year, covering the previous calendar year's data. EPA recommends testing a private well every year for total coliform bacteria, nitrates, total dissolved solids, pH. EPA does not regulate private wells.

Where to look

Your utility's Consumer Confidence Report: Community water systems must deliver a Consumer Confidence Report by July 1 each year, covering the previous calendar year's data.
Private wells (EPA): EPA recommends testing a private well every year for total coliform bacteria, nitrates, total dissolved solids, pH. EPA does not regulate private wells.

Then match what you find to a filter certified for it: what removes each contaminant.

Sources

Your utility's Consumer Confidence Report
Private wells (EPA)

Last checked 2026-10-23.