Copper in Tap Water

Copper is a metal that usually enters drinking water from the corrosion of household copper pipes and brass fixtures rather than from the source water. Small amounts are an essential nutrient; the concern is elevated levels.

The federal reference is the action level of 1.3 mg/L (90th percentile). It triggers treatment steps; it is not an enforceable maximum contaminant level. The health-based goal (MCLG) is 1.3 mg/L. PurityMap reads every measurement against its stated benchmark and never sets its own.

Copper household plumbing, Brass fixtures and fittings, Corrosive water chemistry.

Short-term exposure to elevated copper can cause gastrointestinal upset; long-term exposure above the action level is associated with liver and kidney effects, and is a particular concern for people who cannot regulate copper. Because copper is usually added at the tap, a first-draw sample after water has sat overnight tends to read highest.

Treatment technologies commonly certified to reduce Copper include Reverse osmosis, Corrosion-control / pH adjustment, Flushing standing water before use. Match the exact certified claim to your water before buying. Holding a format is not the same as holding the claim.

In PurityMap's published record, 78 cities have a published Copper value from the federal Lead & Copper Rule record and utility Consumer Confidence Reports, 54 of them above the federal action level. This is the scope of our record, not a national prevalence estimate.