Copper occurs most commonly in drinking water due to corrosion of copper pipes. Such corrosion can have many causes, but is usually a symptom of overly acidic water or high TDS, chlorine, or oxygen content.
Rather than set a maximum contaminant level (MLC) for copper, the EPA has set a treatment technique, meaning “an enforceable procedure or level of technological performance which water systems must follow to ensure control of a contaminant.” The technique regulation for copper demands that water systems have some method of controlling the corrosivity of the water to prevent corrosion and keep the level of copper below 1.3 mg/L.
Copper corrosion can cause pinhole leaks, metallic odors, and blue staining of fixtures and appliances, as well as adverse health effects when ingested. These effects include gastrointestinal issues and liver or kidney damage, according to the EPA.
You can test for copper with an at-home test kit or by sending your water in to a lab. All of our corrosion test kits include a copper test.
Once you’ve confirmed copper’s presence in your water, your best course of action is to look into a calcite neutralizer. A calcite neutralizer will neutralize the acidity in your water that is often the cause of copper corrosion, cutting your problem off at the source. Another alternative, if your pipes are heavily corroded, is to replace your piping altogether.
If you suspect the copper in your water is from groundwater leaching, and not copper corrosion (though this happens much less frequently), you should consider a point-of-use RO system to filter copper particulate right at the faucet.