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Drinking Water Contamination
Drinking Water Contamination
Drinking water can become contaminated through natural and human activity. Contaminated drinking water may cause health problems. Learn more by visiting the US Environmental Protection Agency Report on the Environment Drinking Water page.
How Water is Contaminated
Natural sources. Naturally-occurring contaminants can be found in rocks and soil that groundwater and surface water run through or over. This water eventually becomes our drinking water.
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.
Industry and agriculture. Human-made contaminants such as pollution from manufacturing facilities, agricultural runoff and improper waste disposal can contaminate drinking water.
Treatment and distribution. City/community residential water supplies will sometimes treat water to remove contaminants. However, these treatments can sometimes react, creating a harmful chemical or substance (a disinfection byproduct, like Total Trihalomethanes or TTHMs) or causing problems with the pipes that the water flow through. Regular water testing and treatment generally removes or reduces contamination and makes sure the water chemistry is safe for the pipes.
Improper private residential well maintenance. A private residential well system that is not properly maintained can lead to drinking water contamination. Your wellhead and well cap keep flood water, polluted rainwater, insects and small animals from getting into the well. If these get in through cracks and openings on your wellhead or well cap, it can make your water unhealthy.
Have a drinking water concern?
No matter where your water comes from you can call MDHHS at 800-648-6942.
Drinking Water Contaminant Fact Sheets
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.
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Arsenic
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 Arsenic in Drinking Water Fact Sheet.
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Coliform Bacteria
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.
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Copper
Copper is a metal found naturally in the environment. It can be found in ground and surface water that is used for drinking water. It may also be found in your home's plumbing, farming materials, mining run-off and in wastewater. Some copper is necessary for your body, but too much can cause stomach upset or other health concerns if you have been diagnosed with Wilson's Disease.
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Fluoride
Fluoride occurs naturally in soil and can be found in fertilizer and waste run-off from factories. It is also added by public water supplies because it's good for our teeth in small amounts. Too much fluoride may cause health problems such as white spots on teeth, painful damage to bones or lower IQ.
- To find out more about fluoride in public drinking water supplies, view the Community Water Fluoridation webpage.
- Wells with high levels of fluoride have been found in Houghton and Keweenaw Counties. For more information visit the Fluoride Advisory page on the Western Upper Peninsula Health Department website.
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Iron
Iron occurs naturally in soil and rocks. It is also found in plumbing materials. Some iron is necessary for health, but too much may cause health problems such as stomach problems and nausea.
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Lead
Lead found in drinking water is soluble or particulate. Soluble lead is lead that is dissolved in water. Particulate lead is small pieces of lead from lead-containing material. Either type of lead can get into your drinking water when pipes or faucets containing lead begin to break down or dissolve. The amount of lead that can end up in drinking water depends on:
- Water chemistry (what is in the water).
- Contact with lead-containing items (if it passes through lead plumbing or fixtures).
- Water use (how often and in what amount water runs through plumbing and fixtures).
- Construction or plumbing repairs in the street or home (particulate lead can be released).
Visit Michigan.gov/MiLeadSafe or Michigan.gov/GetAheadofLead to learn more about lead.
- How to Find Out if Lead May Be in Your Drinking Water - English Version
- How to Find Out if Lead May Be in Your Drinking Water - Arabic Version
- How to Find Out if Lead May Be in Your Drinking Water - Spanish Version
- Lead in Drinking Water - English Version
- Lead in Drinking Water - Arabic Version
- Lead in Drinking Water - Spanish Version
- Steps to Get Ahead of Lead in Your Drinking Water - English Version
- Steps to Get Ahead of Lead in Your Drinking Water - Arabic Version
- Steps to Get Ahead of Lead in Your Drinking Water - Spanish Version
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Manganese
Most manganese in water comes from naturally occurring sources. However, industrial activities can also release manganese into the environment. Manganese is necessary for the body in small amounts, but too much, especially for infants, can cause health problems like harm to the nervous system and motor skills.
To find out more about manganese in drinking water, view the view the Manganese in Drinking Water Fact Sheet.
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Nitrate & Nitrite
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.
- Nitrate and Nitrite in Drinking Water for Well Owners
- Nitrato y Nitrito en el Agua Potable Para Propietarios do Pozos
- النترات والنتريت في مياه الشرب لمالك آبار المياه
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PFAS
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.
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Uranium
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.
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VOCs
VOCs are chemicals that easily evaporate into the air. There are many different VOCs. Many products commonly used and stored in homes and garages contain VOCs, including paint, cleaners and gasoline. Some VOCs can cause more harm to your health than others. It is important to follow storage and use directions on packages for this reason. It is also important to note that not all VOCs can be smelled at levels where they can cause harm and not all VOCs that you can smell will cause harm.
VOCs can also get into drinking water. This can happen when places like industrial facilities, gas stations or dry cleaners leak things with VOCs like:
- Petroleum fuels.
- Hydraulic fluids.
- Refrigerants.
- Paint thinners.
- Dry cleaning agents.
Common VOCs in chlorinated drinking water are disinfection by-products, which form when chlorine interacts with organic matter in water. This can happen when chlorine is added to drinking water to disinfect bacteria and other germs.
Public water supplies are tested regularly to make sure they meet safe drinking water standards. Many public water supplies test for and closely monitor disinfection by-products like Total Trihalomethanes (TTHMs) and haloacetic acids (HAAS).
Because of the many different VOCs there are, the levels of chemicals in your area 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.
- Learn more about your county's groundwater VOC levels by viewing the EGLE Water Quality Map for VOCs.
If you have questions about VOCs in your drinking water, call MDHHS at 800-648-6942.
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Zinc
Drinking water standards for public water supplies are created by agencies such as the United States Environmental Protection Agency. Learn more about contaminants public water supplies are required to comply with or encouraged to comply with.
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 MDHHS at 800-648-6942.