By: Ashley Mark, MDHHS; Sara Pearson, EGLE; Lon Nordeen, MLSA
There are over 1 million private residential wells in the state of Michigan, serving over 2.6 million people statewide. That is over 30% of Michigan residents! A private residential well supplies water to a single-family home. Water is pumped from groundwater using a water well. To learn more about the types of private wells, well components, and well construction visit the United States Environmental Protection Agency website.
As a private residential well owner, you are responsible for the quality of your drinking water. It is important to monitor your well system and your drinking water to protect the health of you and your family. Maintaining your well involves regular inspections, testing, and if required, treatment. For more information about how to properly maintain your private residential well system, view the Drinking Water Well Maintenance Fact Sheet.
Proper well maintenance is a great way to protect the quality of your drinking water. However, testing your drinking water for contaminants is the only way to know for sure what is in your drinking water. The Michigan Department of Health and Human Services (MDHHS) recommends testing annually for Coliform Bacteria, E. coli, Nitrate, and Nitrite. Visit the Care for MI Drinking Water Drinking Water Testing page for more information about what to test for and how to have your drinking water tested.
In addition to MDHHS recommendations for testing, sometimes it is appropriate to consider testing for other contaminants. If you are a private residential well owner, it is important to understand what natural and human-made contaminants may be in the groundwater that you use for drinking water. For example, if your home is near a potential source of contamination, you might consider expanding what to test for. Learn more about what might be in the groundwater you drink, or contact your Local Health Department to learn about local concerns or recommendations.
Still have questions or want to learn more? The MDHHS Care for MI Drinking Water website is where you can find more information about drinking water contaminants, testing, how to understand test results, treatment options, and more. Here you can also subscribe to receive the Drinking Water and Health newsletter in order to stay up to date on new initiatives happening through the MDHHS Division of Environmental Health’s Statewide Drinking Water Campaign.
In addition to understanding how your well works, maintenance needs, and monitoring that needs to be done to ensure that your well is properly functioning and provides safe drinking water, protecting source water is another important part in maintaining the quality of your water.
Water is constantly being recycled as it moves through the hydrologic cycle. The water in rivers, lakes and streams evaporates and condenses in the atmosphere to become clouds that eventually release the water back to the ground in various forms of precipitation. Precipitation replenishes our lakes, rivers and streams and also seeps into the ground recharging the groundwater supply. Groundwater discharges into some surface water bodies and some surface water bodies recharge the groundwater. This is a very generalized description of the hydrologic cycle as there are many ways that the water may be used throughout this cycle. For example, rainwater may be collected and used for watering a garden surface water and groundwater may be used in homes, businesses, and industries for many purposes. In your home it is commonly used for drinking, cooking, and washing.
Once the water is used for these purposes, it is discharged either to a sanitary sewer system for treatment or to a septic system. The septic system is designed to collect solids in the tank and discharge the liquids to the ground. The soils in the subsurface act as a filter removing bacteria like coliforms from water as it moves through the soil and eventually recharges the groundwater. Groundwater may discharge to a surface water body, it may be drawn into a well for use again, or it may remain in the aquifer for quite some time. Overall, it is constantly reused for many purposes. Therefore, Michigan’s Public Health Code and local sanitary codes specify minimum separation distances between a well and a septic tank, septic tanks and wells from surface water bodies and floodplains, and specific construction materials and specifications for both wells and septic fields. A well that is too close to a septic tank may draw in water that is not adequately filtered and pose a health risk from the presence of bacteria. Septic tanks that are too close to surface water bodies can result in unfiltered waste being discharged to the water body causing a health risk to swimmers from elevated coliform bacteria and can also result in the growth of harmful strains of algae that can be lethal. Wells that are too close to surface water bodies may draw in surface water that is not as well filtered as the groundwater and is likely to have other types of harmful bacteria and parasites like Giardia that cause illness in people and pets.
As water is used and is constantly being recycled, it may be mixed with detergents, hazardous substances, or may even be in contact with naturally occurring hazardous substances like arsenic. Water mixed with some of these substances can be odorless, tasteless, colorless and require more treatment than the typical septic or sanitary treatment offers. Therefore, source water, which is the water that you drink, protection practices become important. Contaminants released to the ground have a high probability of affecting the groundwater and surface water bodies which is why proper disposal of wastes is critical. Some everyday actions that can be taken to protect surface water and groundwater. The US Environmental Protection Agency offers some great suggestions you can take to protect your water.