Lead and Copper Information

Grand Rapids Public Utilities (GRPU) is committed to providing safe, reliable drinking water that meets all state and federal drinking water standards. As part of that commitment, we routinely monitor our water system for lead and copper and work closely with the Minnesota Department of Health (MDH) to ensure compliance with all drinking water regulations.

Lead & Copper Monitoring

Federal regulations require public water systems to collect drinking water samples from a designated number of customer taps to monitor for lead and copper.

Under the Lead and Copper Rule (40 CFR 141.86), as implemented by Minnesota Rules, part 4720.0350, compliance is determined using EPA-established Action Levels for lead and copper. If more than 10% of sampled homes exceed an action level, the water system must take additional steps to reduce corrosion and protect public health.

Copper Action Level Exceedance

Recent monitoring found that more than 10% of the homes sampled exceeded the EPA copper action level of 1,300 parts per billion (ppb).

An action level exceedance does not mean the drinking water is unsafe. Instead, it indicates that additional actions are required to reduce the amount of copper that can enter drinking water through household plumbing.

What GRPU Is Doing

Grand Rapids Public Utilities has been approved by the Minnesota Department of Health to implement an Optimal Corrosion Control Treatment.

Implementation will begin in the coming months, pending final approval from the Minnesota Department of Health.

This treatment is designed to reduce the corrosion of household plumbing materials, helping minimize the amount of lead and copper that can dissolve into drinking water over time.

What Causes Copper in Drinking Water?

Copper is a naturally occurring metal that is commonly used in household plumbing.

The water leaving GRPU's treatment plant contains very little copper. Copper typically enters drinking water as it passes through household plumbing, particularly when:

Water has been sitting in pipes for several hours.
Plumbing is relatively new and has not yet developed a protective mineral coating.
Hot water is used for drinking or cooking.
Water softeners or certain water conditions increase corrosion.

Health Information

Copper is an essential nutrient and is safe at normal levels.

However, drinking water containing elevated copper over a short period may cause:

Nausea
Stomach cramps
Vomiting
Diarrhea

Long-term exposure to elevated copper levels may increase the risk of liver or kidney damage in some individuals.

People with Wilson's disease and infants under one year of age are more sensitive to copper and should consult their healthcare provider if they have concerns.

How You Can Reduce Copper Exposure

You can help reduce copper levels in your drinking water by following these simple steps:

Let the Water Run

If water has been sitting in your plumbing for more than six hours:

Run cold water for 30–60 seconds before using it for drinking or cooking.
If your home has a lead service line, run the water for 3–5 minutes.

Using water for showering, laundry, or washing dishes first is an easy way to flush your plumbing.

Use Cold Water

Always use cold water for:

Drinking
Cooking
Preparing infant formula

Hot water can dissolve more copper from household plumbing than cold water.

Consider Testing Your Water

If you remain concerned about copper in your drinking water, you may have your tap water tested by a Minnesota Department of Health accredited laboratory.

Testing is especially recommended if an infant or someone with Wilson's disease regularly drinks your tap water.