Copper in Drinking Water

Copper piping and fittings are commonly used in home plumbing systems. When well water is acidic, copper from the home’s pipes and fittings dissolve into the drinking water. Water from shallow springs and dug wells is more likely to be acidic. In rare instances, high copper levels in well water are caused by pollution from industry or metal salvage.

Health Concerns: Is copper harmful to my health?

Copper is needed to make red blood cells. However, drinking water with high amounts of copper can cause stomachaches, vomiting or diarrhea.

Very young children are sensitive to copper and long-term exposure can be harmful to their liver. For this reason, it is important not to use water with too much copper when preparing baby formula.

Water containing copper can also leave blue-green stains on plumbing fixtures or have an unpleasant metallic taste. Staining generally begins at 1.0 mg/L (milligrams per liter). Staining doesn’t necessarily mean the water’s copper level is too high for drinking, but you should test for copper if there is blue-green staining.

Testing: How do I know if copper is in my water?

The Health Department recommends testing your private water source for copper every five years.

Levels of copper in drinking water are regulated by the Environmental Protection Agency (EPA) and the State of Vermont. The action level for copper is 1.3 mg/L (milligrams per liter), a level that is enough for the body to make red blood cells, but will prevent health effects. Order a test kit for copper

The Health Department recommends that private well owners also test their water for lead when copper results are elevated because older plumbing solder and fixtures can contain lead. Learn more about lead in drinking water

Treatment Options: Can I remove or lower the levels of copper in my water?

Copper can be lowered or removed from drinking water with a few different methods and treatments.


Flushing out water that has been sitting in pipes is one simple way to remove high copper levels from plumbing. Test for the highest level of copper by collecting a sample before flushing the plumbing. To flush, let the cold water run until it is as cold as it can get. This means the water is flowing directly from the well or the town water main. This flush should be done if the water has been sitting in the pipes for more than six hours, which is usually first thing in the morning or after the work day. Test the water after flushing to show that flushing was successful in lowering the copper level.

Reverse Osmosis

This system uses a synthetic membrane that allows water to go through but leaves copper behind. The membrane is continually rinsed. It is usually installed under the kitchen sink (the point-of-use), but can also be installed as a whole house system (the point-of-entry).

Countertop (plug-in) Distillation Units

These units boil water and then recondense the steam. The copper is left behind during this process, along with hardness and other minerals. These units can produce several gallons of copper-free water per day.


Neutralizers can be added to the water to make it less acidic as it enters the home piping. This “neutralized” water will be less likely to dissolve copper. Talk with a water treatment professional about this option.

When possible, replace copper piping and fittings with plastic plumbing approved for drinking water systems.

Re-test for copper after any treatment system is installed to make sure levels are below the action level.