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What Might Be in the Groundwater You Drink?

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Department of Health and Human Services

What Might Be in the Groundwater You Drink?

If you are a private residential well owner, it is important to understand what contaminants may be in the groundwater that you use for drinking water. Both natural and human-made contaminants can sometimes be found in groundwater. When you know what contaminants may be in groundwater and where they can be in our environment, you can help protect your drinking water and health.

Cutaway illustration of land, an underground aquifer, and layers of soil and rock.Naturally occurring contaminants can be found in rocks and soil; and lakes, rivers, and groundwater used for drinking.
 
In Michigan, contaminants in groundwater can vary depending on where you live. Some parts of the state are known for having higher levels of certain contaminants than others.

Diagram showing a home connected to a drinking water well, and different sources of contamination in the groundwater aquifer the well draws water from. Contamination sources include airports and military bases, manufacturing facilities, unlined landfills, and farm field applications. Human activity may contribute to contamination of the environment. When chemicals are released into the environment, they can seep into groundwater.
 
Common human-made contamination sources are manufacturing facilities, agricultural runoff, and waste disposal. While these sources have the potential to contribute to contamination, precautions can be and often are taken to prevent contamination from these sources.

Some contaminants can be harmful to your health if you are exposed to certain levels. Select the name of each contaminant to learn more. This important information could help you decide if you should test your drinking water.

  • Michigan has naturally higher arsenic levels in groundwater. Learn more about your county’s groundwater arsenic levels by viewing the EGLE Water Quality Map for Arsenic.

    Contaminant levels may vary depending on where you live within your county. To find out more about groundwater arsenic in your area, contact your local health department.

    To find out more about arsenic in drinking water, view the CDC’s Arsenic ToxFAQs.

  • Some areas of Michigan have been found to have higher nitrate levels in groundwater. Nitrate and nitrite may be more common in shallow wells near agricultural areas. Learn more about your county’s groundwater nitrate levels by viewing the EGLE Water Quality Map for Nitrate.

    Contaminant levels may vary depending on where you live within your county. To find out more about groundwater nitrate in your area, contact your local health department.

    To find out more about nitrate and nitrite in drinking water, view the Nitrate and Nitrite in Drinking Water Fact Sheet.

  • Coliform bacteria are found in soil, surface water, on plants, and in the intestines of warm-blooded animals and people. Poorly maintained septic systems can be a source of coliform bacteria, especially E. coli, which can make you sick.

    To find out more about coliform bacteria in drinking water, view the Coliform Bacteria in Drinking Water Fact Sheet.

  • The most common sources of Per- and polyfluoroalkyl substances (PFAS) in groundwater are airports, military bases, manufacturing facilities, unlined landfills, and farm field applications. 

    Check for PFAS contamination sites in Michigan by viewing the Michigan PFAS Sites Interactive Map.

    To find out more about PFAS in drinking water, view the PFAS in Drinking Water Fact Sheet.

  • Fluoride occurs naturally in soil and can be found in fertilizer and waste run-off from factories. It's good for our teeth in small amounts, but too much of it may cause some teeth problems. 

    To find out more about fluoride in drinking water, view these Questions and Answers about Fluoride in Drinking Water from the EPA.

  • Uranium occurs naturally in some areas. For example, naturally occurring uranium has been found in Western Upper Peninsula bedrock and groundwater.

    Wells with high levels of uranium have been found in Baraga, Houghton, Keweenaw, Gogebic, and Ontonagon Counties.

    What you need to know about Uranium – Western UP Health Department

    To find out more about uranium in drinking water, view the CDC’s Uranium ToxFAQs.

  • Most manganese in water comes from naturally occurring sources. However, industrial activities can also release manganese into the environment.

    To find out more about manganese in drinking water, view the CDC’s Manganese ToxFAQs.

  • Common sources of Volatile Organic Compounds (VOCs) in drinking water are industrial releases, landfill runoff, and chemical or fuel spills and leaks. Learn more about your county’s groundwater VOC levels by viewing the EGLE Water Quality Map for VOCs.

    Contaminant levels may vary depending on where you live within your county. To find out more about groundwater VOCs in your area, contact your local health department.

    Go to Agency for Toxic Substances and Disease Registry to learn more about VOCs. 

Protect Michigan's Groundwater

As a state, community, and individuals, we can all help protect Michigan's groundwater. Let's work together to ensure we have safe groundwater to use for drinking!

 

Michigan Initiatives

There are some initiatives in place to improve water quality around our great state! These are just a few:

Community

As a community, we can all protect our environment, and our drinking water sources!

So many communities have activities and programs in place that residents can get involved in! Learn about easy ways that you can step up for your environment within your community.

Private Residential Well Owner

As a private residential well owner, having a well means you are responsible for your own water system!

This includes protecting the groundwater used for drinking, taking care of your well system, testing your drinking water, and understanding your test results to make the best decision for your health.

Learn more about these activities!

To stay up to date with current resources and opportunities being offered through the program, subscribe to the Drinking Water and Health newsletter.

If you have questions, please contact the MDHHS Drinking Water Hotline at 844-934-1315.