Private residential water wells

© Mikael Damkier

By Michael Scott

Michigan has over one million private residential wells, serving an estimated 2.6 million people, comprising about 30 percent of all residents, according to the state. In Oakland County alone there are an estimated 100,000 private residential wells.

A private residential well supplies water to a single-family home by pumping water from groundwater using a water well.

Residents with a private well should follow recommended guidelines to monitor their well system and the quality of their drinking water for family members and guests. Yet there is no requirement to test or monitor water quality in Michigan or Oakland County even though the Michigan Department of Environment, Great Lakes and Energy (EGLE) regulates the water well drilling industry. Water samples are collected by Oakland County during the final inspection of a newly constructed well. Well approval is based on the final inspection observations and results of the water samples, according to Mark Hansell, public health chief for the Oakland County Health Division.

The county also requires that homeowners secure a construction permit from its health division for any water well construction project, whether it is a first-time well or a full well replacement.

Well system maintenance projects such as the installation of a new water pump or water tank do not require a permit. However, the well driller handling the project and installation must follow certain Oakland County guidelines for the permit to be issued. To ensure those guidelines are followed the Oakland County Health Division will often conduct as many as three or more site visits of a new well construction site before the project is completed, Hansell said.

“We’ll do an initial site visit and look for threats to the safety of the drinking water and other potential areas of concern,” Hansell said. “Then you have the inspection during the construction phase, and the final review before the well is fully installed. If there’s a need to drill a new (water) well, then the permit is required.”

An approved permit in Oakland County also requires water quality testing for bacteria samples like chloroform, and nitrate samples, which include human waste, pesticides and other items that can runoff into the ground. The county issues a permit once minimum water quality standards are met by an applicant.

“After the permit is issued, we do one inspection during the construction process,” Hansell said. This typically includes a meeting with the well driller to verify the well location and construction requirements.

Counties throughout Michigan may have slightly different permit requirements or ordinances that guide homeowner requirements, so it is always advisable to check with the local county office, Hansell said.

Michigan counties can enact ordinances that require well testing when a property transfer occurs, said Brandon Morrill, supervisor of the source water unit for EGLE. “We’ve also (seen) that water tests are usually required by most mortgage lenders and always by FHS/VA type loans.”

The Michigan Water Well Construction and Pump Installation Code guides contractors and residents of Michigan well owners. It assures that water wells are constructed, operated and decommissioned in a technically sound manner for the safety of residents and protection of acquifers.

The state water well construction code also outlines specifications for wells made of all materials, including galvanized black steel well casings and those made of PVC. Wells constructed today are often constructed using PVC because the price of galvanized steel and the associated labor that is required can be cost prohibitive for many homeowner budgets. Even so, building a new residential well is difficult and even if a homeowner has the technical knowledge and active skills, they still must meet code. That’s why EGLE officials recommend that a licensed professional should conduct the full well inspection.

“It’s not often a project for a (lay) person,” said David DeYoung, environmental quality specialist with a specialization in well construction with EGLE. A properly constructed well prevents it from contaminants like fertilizer, Hansell said.

Well issues are more likely based on the age of a well but human-related accidents like hitting the well cap with a lawnmower or an accidental crack in the casing or displacement of the cap are possible. This is especially possible with a well that is made from steel.

“Steel has a tendency to corrode. That can allow bugs, bacteria and dust to get inside the well,” DeYoung said. “If you have a bigger issue, there may be a contaminant in the aquifer.”

One of those potential large issues could occur when water from an upper aquifer creates a conduit or discharge to a lower level aquifer. While rare, in this case contaminants could seep into an aquifer that a neighbor uses, DeYoung said. It is possible, but somewhat rare, that a property owner could be liable for damages.

State residents have been asked to follow different iterations of well construction code over the years. That has included evolving materials for grouting, requirements for proper plug spacing, and other strategies to prevent surface contamination at the aquifer.

Homeowners should pay close attention to whether the area around wellhead includes items or materials that could negatively impact it. For example, homeowners should never store, use or dump harmful materials such as paint, fertilizer, pesticides and motor oil near the wellhead. Fertilizer in particular should not be over-applied near the wellhead.

That wellhead should be kept at least 12 inches above the ground. It’s advisable to slope the ground away from the wellhead to prevent the puddling of water or other objects near the wellhead as well. That prevents standing water, which can accelerate the collection of contaminants around the well opening.

That area should also remain free of shrubs and trees, overgrowth, and other vegetation especially around the well cap. and homeowners will want to easily be able to access their wellhead for maintenance and/or for pump replacement.

“You want to keep that area clear,” DeYoung said. “(And) you want to make sure you can easily find the wellhead. That can help you quickly address an issue before it becomes a (very expensive) project.”

Another maintenance recommendation is to react quickly to issues uncovered through research and testing, and obvious visual or issue such as cloudy or dirty looking water. Odors, particularly the smell of “rotten eggs” and the loss of water pressure or continual pump cycling signifies an issue that requires a resolution, Hansell said. Wellhead defects should be addressed to ensure the defect is fixed to prevent contaminant seeping. A positive bacteria test likely means there are one or more structural issues with the well that require immediate attention.

In an effort to help spot residential well challenges, homeowners should confirm their wellhead information and document such as depth, pumping rate, pump and pressure tank information, drilling method and date of completion. This allows them to better react to issues, and to provide the information sought by private contractor or well drillers if asked.

The Oakland County Health Division offers a range of educational resources to help homeowners conduct proper residential well maintenance. The county also has two certified labs in Southfield and Pontiac where water is tested for common contaminants. Residents interested in getting their water tested can pick up a kit for a small fee and collect the water from their property.

Once residents collect their well water, they can drop off the sample at one of the labs. Results are often available within a week through the Oakland County labs. Homeowners can also get their water tested for contaminants at private labs around the state.

Hansell believes that testing the drinking water from a well is one of the most critical maintenance responsibilities a homeowner has. He said he doesn’t care where residents get their water tested but stresses the importance of using a lab certified in groundwater quality tests. He recommends that homeowners test their well water for bacteria and nitrates annually.

“That’s really the best thing you can do is to get your water checked,” Hansell said. “It’s important to know what’s in there. I can’t emphasize the importance of well water testing enough.”

Water well testing can be managed for other contaminants as well, Hansell said. He recommends the testing of arsenic and other dissolved solids every two to three years. Arsenic is a naturally occurring substance that can get into groundwater through erosion and can cause adverse health effects, especially for people with compromised immune systems. Sulphur is another substance that is more of an aesthetic challenge for most homeowners given the propensity to cause unpleasant odors.

“Some of these substances aren’t going to cause many health effects but they are a nuisance regardless,” Hansell said.

Local health departments are the primary regulatory agencies responsible for inspecting residential wells. They are required to maintain a list of environmental contaminants within their jurisdiction, and they consider this information when they issue permits for new wells. Those health departments work with Michigan residents to ensure compliance with monitoring and routine inspections of Type II and III wells.

A Type II water system serves any nonresidential facility that provides water for drinking or domestic purposes to 25 or more persons at least 60 days out of the year, according to Oakland County. On the other hand, a Type I well is generally one that is drilled thousands of feet below the lowermost underground source of drinking water. Approximately 800 operational Class I wells exist in the United States, according to EGLE.

All other public water supplies that provide drinking water not considered a Type I or Type II are considered a Type III system. Some examples are small apartment complexes or condominiums, duplexes and very small businesses.

Iron is commonly found in the ground around Oakland County. While iron rarely results in human health issues, it is an aesthetic nuisance that causes brown discoloration around or on a house, often from sprinkler systems.

Other important maintenance tips Hansell suggests include inspecting the well casing of a water well to ensure there is no damage or areas that contaminants could get into. There should also be a working vent under the water well cap and a fully functional screen connected to the cap to keep items from accidentally entering the well.

“You should visually inspect the area around and outside of your well,” Hansell said. “Most modern wells have visual clues that will be (obvious) if there’s an issue that is a concern.” Hansell says many water wells built since the late 1960s would actually be considered modern because of changes in their construction at that time.

If a well does get contaminated, private homeowners aren’t required to have an expert install a new well, but Ruth Kline-Roback, an outreach specialist in with expertise in community-based water resources management issues at the Michigan State University School of Agriculture, strongly recommends it.

“You want to contact a licensed water well driller because if you don’t know what you’re doing, it can be a pretty serious problem,” she said. Residents can ask potential well drillers for certifications, licenses and referrals. “They have specialized knowledge and will know what is common in the area (of the state) where you live, and how to best put together a plan based on the topography and what’s likely in the ground.”

Since county inspections are not required whenever there is a transfer of property, a regular home inspector can provide a good overview of the condition of a residential well, Morrill said. Inspectors possess varying levels of knowledge on the issue, so homeowners should conduct online research and ask questions. Morrill recommends that residents in the process of a property transfer that includes a residential well also connect with their local health department which may have a better understanding of the well characteristics for that region.

Most private residential wells around the state are drilled, especially in Oakland County where there is little clay in the ground, said Kline-Roback. Homeowners with private wells should always find out how their well was constructed and how it has been maintained.

EGLE recommends that residents use free online tools to help complete an annual well assessment. For example, the Be Well Informed website provides a 10-minute step-by-step inspection of a home’s private residential well. It is not intended to be a definitive assessment of a system, but additional resources assist owners with recommended steps.

“There are online tools that provide detailed information for homeowners that helps them understand the next steps and recommendations for well knowledge and maintenance,” Morrill said. “You want to get as much information about your well so you can make (informed) decisions along with any experts that you are relying on.”

There are several online sources available that provide this and other relevant information for residential well owners.

Be Well Informed: www.bewellinformed.info. Provides feedback for the public about common contaminants that may affect well water. 

Care for MIWell: www.michigan.gov/mdhhs/safety-injury-prev/environmental-health/topics/care-for-mi-drinking-water/mi-well. Information and resources from the Michigan Department of Health & Human Services to support the maintenance of private residential wells.

Oakland County Well and Water Services: www.oakgov.com/community/health/public-health-services/environmental-health/well-and-water-services. Reminders, resources and tips for private residential well owners.

Private Residential Water Well Testing (EGLE): www.michigan.gov/egle/about/organization/drinking-water-and-environmental-health/water-well-construction/private-well-testing. Information about well water tests available through the state.

Water Well Viewer (EGLE): www.mcgi.state.mi.us/waterwellviewer. Search and access information about private residential wells around Michigan.

Wellogic: www.egle.state.mi.us/wellogic. The statewide groundwater database. It can provide details on well depth, where they are routed and more for hundreds of thousands of wells around the U.S. Not every well is in the database.

Some homeowners may want to get their water tested for Per- and polyfluoroalkyl substances (PFAS), which are complex group of synthetic chemicals that have been used in consumer products for around seven decades. Homes near current or former industrial sites and fire stations are advised to get tested for PFAS every few years. Unlike most other water tests, the PFAS test typically costs a few hundred dollars.

The standard bacteria and nitrate tests available through direct pickup are available through EGLE or Oakland County often cost $20 or less. Private labs also offer these tests, but the fees may be higher.

EGLE offered free residential well testing kits in recent years but ran out in 2024 due to high demand. Similar kits are available to purchase from the EGLE drinking water lab, including tests for arsenic and lead. State lab bottles are available by calling 517-335-8184 or contacting the Oakland County Health Department at 248-858-1280 or through email at health@oakgov.com.

“Most water tests are affordable, but you need to know what test to ask for,” Kline-Roback said. “You’ll want to confirm (with a lab) what (contaminants) you are looking to measure.”

The bottom line is that it’s up to homeowners to ensure their water is safe to drink. They must take the initiative. That includes proper ways to use and store chemicals to treat a private well. Michigan counties require different types of tests and requirements, including well and septic permits.

“I was pleasantly surprised by how many homeowners responded to the offer of free water tests when EGLE offered it,” Kline-Roback said. “That might indicate that offering the tests for free really does (motivate) more homeowners to get their well tested.”

Human activities can impact the ground quality around a wellhead. That’s why gasoline or engine oil should never be poured on the ground around a residential water well, Hansell said. If that happens and there are cracks along the well casing, those materials could impact the water table.

“In many instances we can set up or recommend a filtering system that will help solve the problem without having to (invest) in a costly well replacement,” Hansell said. “It will depend on damage to the well and the type of contaminants we are seeing but you can filter most (harmful) items. Solutions to an issue are often easy and affordable.”

Unlike a home’s roof, hot water heater or other notable expenses, a residential well can operate efficiently and effectively for decades, even 60 years or more if properly maintained, Hansell said. There’s no standard timeframe by which a water well “must” be replaced.

Hansell does recommend one additional tip for homeowners that will come in handy if there’s a flood caused by heavy rains, a hot water heater malfunction or other issues.

“People should know which breaker controls their well pump,” Hansell said. “You need to know that in case of a (water) emergency, and you can help to shut things down.”

The natural geology of the area is a major factor in why one residential well may be dug at a completely different depth than a well right next door, Kline-Roback said.

“It’s based on how the glaciers were formed so it has created this system of multiple aquifers,” she added.

An issue with one well could cause an issue in another well if the two properties are on the same aquifer. That’s because any drilled well might reach usable water at a different depth depending on which aquifer it reached.

“You might drilled a well 80 feet on one property and 200 feet right next door,” Kline-Roback said.

The composition of the ground matters as well, Kline-Roback said. For example, sand and gravel is more likely to cause water contamination because there is more space between the materials.

Land in Oakland County and throughout much of Michigan is homogeneous, signifying that many neighborhoods and properties are on land that have similar characteristics. Aquifers sit at different depths, and a certified well driller is better able to determine how deep a well should be drilled to find the most suitable aquifer on a property. DeYoung said some homeowners want to drill a new well on their property for a small back garden fountain, but even that type of project can be both extensive and complicated, depending on the local geology.

“I always maintain that knowledge is your best protection for drinking water,” Kline-Roback said. "Older wells tend to be more susceptible to contamination but it depends on how they were made and how deep or shallow they are.”

If drinking water has been contaminated, it can expose people to a variety of pollutants and pathogens that have adverse health impacts;. Public water systems use water treatment and monitoring to protect consumers from such contaminants. However, this is not the case with private wells. Since well owners are responsible for their own wells, they should be aware of their well's potential for contamination and the possible health effects those potential contaminants can have, according to the Environmental Protection Agency (EPA).

Some of the most commonly found contaminants have varying degrees of potential health issues. According to the EPA, water quality concerns for private wells typically include a range of materials that can seep into the ground, causing health issues for residents. Standard water quality concerns for private wells include coliform bacteria, nitrate, nitrite, fluoride, chloride, sulfate, sodium, hardness, and metals like aluminum, antimony, arsenic, boron, cadmium, chromium, copper, lead, iron, manganese, mercury, selenium, uranium, and zinc.

Microorganisms such as bacteria, viruses, and parasites can be found anywhere and contain, among other things, human sewage and animal waste. Private wells can be contaminated by both naturally occurring sources and by human activities, but the volume of human activities are harder to predict and can vary significantly from one property to another, according to the EPA.

People who consume drinking water containing microorganisms can experience gastrointestinal illnesses and infections. Water run-off, leakage from underground tanks and septic leach fields can also cause microorganisms.

The EPA outlines other potential contaminants in private residential wells around the U.S., including:

Nitrate and nitrite, which are present in chemical fertilizers, human sewage, and animal waste. They can contaminate a private well through groundwater movement and surface water seepage and water run-off. High levels of nitrate and nitrite can cause serious health issues for infants.

Heavy metals can leach into drinking water from household plumbing and service lines, municipal waste disposal, natural mineral deposits and other human-made sites. Health risks include acute and chronic toxicity, liver, kidney, and intestinal damage, anemia, and cancer.

Organic chemicals are found in many household products and regularly used in agriculture and industrial organizations such as inks, dyes, pesticides, paints, pharmaceuticals, solvents, petroleum products, sealants, and disinfectants. People who consume high levels of organic chemicals may experience health issues with their kidneys, liver, circulatory system, nervous system, and reproductive system.

Fluoride is present in many aquifers and can be found in private wells. Fluoride is helpful in preventing tooth decay. However, excessive consumption of fluoride can cause skeletal fluorosis, a condition characterized by pain and tenderness of bones and joints, and other issues.­ ­­­­