Skip to Content


How does copper get into my drinking water?

Copper may find its way into water sources in a variety of ways. Erosion of natural deposits of copper in the earths crust can deposit copper in the ground water. Copper pipes are another source of copper in drinking water. Initially, these pipes may leach a small amount of copper in the first year of use, after which concentrations will decrease. If the water is corrosive, however, the plumbing may continue to release copper into the drinking water.

Why use copper plumbing?

Copper plumbing is used because it helps maintain clean water by keeping down microbial growth. After the initial leaching, the inner surface of the pipes forms a hard surface that should reduce further leaching.

Does copper in drinking water affect my health?

Copper is needed by the human body to function properly. Certain enzymes actually depend on copper in order to operate correctly. In addition, the human body possesses a mechanism that regulates the amount of copper in the body. Only at copper levels far exceeding the normal level in drinking water are any adverse health effects present. These symptoms include nausea, diarrhea and stomach upset, which will cease when the source of the excess copper is removed. Only people with genetic diseases that affect the bodys ability to regulate copper, such as Wilsons Disease, need be concerned about their intake of copper at the levels normally found in drinking water.

What are the aesthetic effects of copper in drinking water?

Elevated levels of copper in drinking water may cause the water to have a metallic taste, or may cause blue or green staining of plumbing fixtures. These "aesthetic" effects can occur at low copper concentrations, well below those that would pose a health risk. Because these aesthetic effects may pose a nuisance to consumers, the regulation of copper in drinking water is based upon controlling these low-level aesthetic effects.

What is being done to prevent the copper from entering my drinking water?

The Acton Water District monitors for copper at 29 selected taps throughout town on a regular basis. In order to minimize the levels of lead and copper, the District adds potassium hydroxide to the water to reduce its corrosivity. In addition, the Water District uses a polyphosphate water treatment additive called Aqua Mag which can also help reduce the level of copper in the water.

The regulation of copper in drinking water is quite stringent. The EPA has proscribed an Action Level of 1.3 mg/L for copper in drinking water. If more than ten percent of the samples collected during any monitoring period exceed this level, the water supply must take steps to reduce the copper levels delivered to the tap. Concentrations of copper in the Districts water are generally well below the Action Level.