Drilling in Michigan - A Comprehensive Guide

Geological Overview: Michigan’s Groundwater and Aquifers

Michigan’s Aquifers and Geology: Michigan’s groundwater is found in two primary aquifer systems – glacial drift aquifers (unconsolidated sands and gravels from Ice Age deposits) and underlying bedrock aquifers in sandstone, limestone, and other rock formations. The state’s glacial geology is complex, with multiple glacial advances depositing layers of clay, sand, and gravel across the region. As a result, shallow glacial aquifers are common and supply the majority of water wells. In fact, roughly 70–75% of Michigan’s water wells draw from glacial drift aquifers, which are often nearer to the surface and can yield ample water for domestic and even municipal use.

Glacial drift aquifers are typically unconfined and composed of permeable sands and gravels that vary widely in thickness and extent. In many areas of the Lower Peninsula, glacial deposits range from a few feet to hundreds of feet thick. These materials often form high-yield aquifers: in parts of the state, large-diameter wells in thick sand/gravel can produce over 100–500 gallons per minute. Many household wells in Michigan’s glacial aquifers are on the order of 30 to 150 feet deep, tapping water tables that often lie 10–50 feet below ground. By contrast, in areas where clay-rich glacial till dominates, aquifers are limited and yields are lower. Drillers should be prepared for highly variable conditions over short distances, reflecting the discontinuous nature of glacial deposits.

Underlying the glacial drift are Michigan’s bedrock aquifers, which include sandstone formations (such as the Marshall and Saginaw formations in the Lower Peninsula) and carbonate rocks (limestone/dolomite layers) among others. Wells completed in bedrock can also supply water, though typically at greater depths. It is common for bedrock wells to be on the order of 100–300 feet deep or more, depending on the depth to bedrock and the target formation. Importantly, water quality in bedrock aquifers is a consideration – these formations often contain more mineralized water. In fact, bedrock formations below the glacial layer in Michigan “commonly contain very mineralized water,” and in some parts of the state (e.g. near Saginaw Bay or the southeast near Lake Erie), saline or brackish water may be encountered at roughly 200 feet depth. In the northern Lower Peninsula and much of the Upper Peninsula, fresh water in bedrock may extend deeper (saline water not encountered until 400–900+ feet). Drillers should consult hydrogeologic maps and well logs to understand local depth trends – in general, shallower glacial wells are preferred when available, whereas deeper bedrock wells might be needed where drift is thin (such as parts of the Upper Peninsula or along bedrock high areas). Table 1 summarizes the two major aquifer types in Michigan.

Michigan’s diverse geology means drilling conditions can change over short distances. The Lower Peninsula is essentially a large sedimentary basin: bedrock dips towards the center, and progressively younger rock formations appear towards southern Michigan. Glacial deposits blanket most of this area, sometimes yielding flowing artesian conditions where permeable layers are confined under clays. The Upper Peninsula has different geologic terranes – glacial sediments are present but thinner in many areas, and the bedrock includes ancient igneous and metamorphic rocks in the west (with low well yields) and some porous limestones/sandstones in the east. Notably, flowing artesian wells can occur throughout Michigan when a well taps a pressurized aquifer beneath an impermeable layer. Drillers encountering artesian conditions must follow special construction practices (such as installing casing seals and grout to prevent uncontrolled flow to the surface).

Water Well Permitting Requirements in Michigan

Permit Requirement: Michigan law requires obtaining a water well construction permit before drilling a new well (or deepening an existing well) for drinking water supply. Permits are generally issued by the local county or district health department for private residential wells and most public wells other than large community systems. In Michigan’s regulatory framework, Part 127 of the Public Health Code (Act 368 of 1978) — also known as the Water Well Construction and Pump Installation Code — governs well construction standards and delegates permitting to local health departments (LHDs) for all private wells and small public water supplies. The typical steps in the permitting process are:

• Permit Application: The property owner or well contractor submits an application (and fee) to the local health department **before** any drilling begins. The application includes information about the proposed well location, use, and site conditions.
• Site Review: The health department conducts a pre-drilling site review (often an Office Predrilling Site Review, OPSR) to assess whether the location meets isolation distances and if any known contamination or geologic concerns exist. They verify the well will be located proper distances from septic systems, sewer lines, fuel tanks, etc. (see Isolation Distances below).
• Permit Issuance: If the site and plans comply with requirements, the health department issues a well construction permit. The permit may contain specific conditions (for example, requiring deeper casing if there are shallow contamination risks, or special grouting provisions in certain geologic areas).
• Well Construction: The registered well drilling contractor (see Licensing section) drills and constructs the well according to the state code standards and any permit conditions. After construction, a Water Well and Pump Record (well log) must be completed for the well.
• Inspection and Testing: The local health inspector may conduct a field inspection during or after drilling (Michigan LHDs are required to inspect a percentage of new wells). After the well is completed, water samples (usually for bacteria and sometimes nitrates or other parameters) must be collected from the new well as required by the permit. New wells should also be disinfected after construction per state guidelines.
• Approval: If the well log and water sample results are acceptable, the health department issues an approval, authorizing the well for use. If problems are found (e.g. contamination or construction issues), the well may be not approved for drinking until remedied.

Isolation Distances: Michigan’s well code prescribes minimum separation distances that must be maintained between a well and potential pollution sources. These are critical for permit approval during site review. For example, a drinking water well must typically be at least 50 feet from any septic tank or drainfield, and at least 50 feet from underground fuel storage tanks (for a single-family well), among many other setbacks. Larger public wells (Type I community supplies) require even greater distances (often 200 feet or more from septic systems, fuel tanks, etc.). Table 2 provides a few common isolation distance requirements from Michigan’s code (Part 127 Rules and Act 399 Rules):

Michigan’s isolation distances are designed to protect groundwater quality by preventing direct contamination near the well. Local health officials have some authority to grant variances (deviations) in special cases if site conditions warrant and alternative protections are in place, but in general the above minima must be met when siting a well. Drillers should always verify the proposed well location meets these requirements during the planning stage.

Public Water Supply Wells: Michigan categorizes public water supplies into Type I (community systems serving 25+ residents year-round, e.g. municipalities or subdivisions), Type II (non-community systems like schools, factories, camps, etc.), and Type III (small public systems not meeting Type II definition, often 2-14 connections). All public water supply wells must also follow Part 127 construction code, but there are additional permit steps. **Type I community wells** require state review and approval by the Michigan Department of Environment, Great Lakes, and Energy (EGLE) drinking water program. **Type II and III wells** are usually permitted through the local health departments similar to private wells. Public supply wells often have stricter construction standards (e.g. thicker grout seals, longer casing) and must be sampled for a full range of water quality parameters before use. It’s important for contractors to coordinate with the appropriate agency (local or state) when dealing with a public well to ensure all additional requirements (like plan approvals, hydrogeologic studies for large withdrawals, etc.) are met.

Well Completion and Reporting: After constructing any water well, Michigan requires the driller to submit a well record. The official form for this is the Water Well and Pump Record (Form EQP 2017), which must be completed with details of the well (location, depth, geology encountered, casing, pump, etc.). The well log serves as both a certification of construction and a record for future reference. Michigan law mandates that well logs be submitted within 60 days of well completion – one copy is provided to the well owner, and copies are sent to the local health department and the state’s database. Today, most contractors submit logs electronically via the Wellogic online system, which populates the statewide groundwater database. Failure to file a well log in a timely manner can result in enforcement action, including potential requirement to perform a geophysical log of the well if a log was not kept. In addition, any abandoned well that is plugged must have an Abandoned Well Plugging Record submitted within 60 days of plugging (usually handled by the contractor or owner who performs the plugging).

Key State Agencies and Contacts for Groundwater and Wells

Water well activities in Michigan involve several agencies and programs. The following are the primary state and local entities that drillers should be familiar with:

• EGLE – Dept. of Environment, Great Lakes, and Energy: EGLE is the state environmental agency that oversees Michigan’s Water Well Construction Program (among many other programs). Within EGLE, the Drinking Water and Environmental Health Division houses the Water Well Construction Unit. EGLE is responsible for the overall administration of the well code (Part 127) and contractor licensing, and it directly regulates Type I public water supply wells. EGLE provides technical guidance, issues bulletins and training for well drillers, and maintains the statewide well databases (Wellogic and the older Well Record Retrieval System for records pre-2000). The department’s Water Well Construction website contains links to rules, forms, and educational resources for contractors.
• Local Health Departments (County/District Health): These local agencies are the front-line regulators for most well construction. Michigan has 45+ local health departments that issue well permits, inspect wells, and enforce the well code at the local level. They ensure isolation distances are met and may impose additional local sanitary code requirements. After well completion, the well record and any water test results are typically filed with the local health department for approval. A directory of local health departments is available via EGLE, and drillers should maintain good communication with the health officials in the counties where they work. Local health departments also investigate well complaints and oversee well abandonment in their jurisdictions.
• Michigan Department of Health & Human Services (MDHHS): MDHHS is the state health agency which, through its environmental health sections, provides guidance on household water well safety and private well water quality. While MDHHS does not issue well permits (that’s done by LHDs), it offers resources like the MDHHS Private Residential Wells program which educates homeowners on well maintenance and water testing. MDHHS certified labs also perform drinking water analysis (bacteria, etc.) for new well approvals. Drillers might interface with MDHHS guidance when advising clients on water quality issues or responding to health-related concerns.
• Michigan Geological Survey (MGS): The MGS, currently based at Western Michigan University, is not a regulatory agency but is a key resource for geological information. MGS compiles geologic and hydrogeologic data, including mapping of aquifers, drift thickness, and bedrock formations across Michigan. Drillers and consultants often use MGS publications and maps (such as the Hydrologic Atlas of Michigan) for research into local geology before drilling. Knowledge of the prevailing geology – for example, knowing if a certain area has a shallow clay layer over a sand aquifer, or if bedrock is at 50 ft versus 200 ft – can be gleaned from these resources. While not required, collaborating with MGS or reviewing their data (via GeoWebFace, etc.) can improve drilling success and groundwater investigations.
• Michigan Department of Agriculture & Rural Development (MDARD): MDARD plays a role in the state’s Large Quantity Water Withdrawal program, particularly for agricultural irrigation wells. Michigan law (Part 327, Great Lakes Preservation) requires registration and impact assessment for any new high-capacity well (over 70 gallons per minute capacity, or over 100,000 gallons per day). Agricultural operations often coordinate with MDARD to register such wells via the Water Withdrawal Assessment Tool. Drillers installing high-capacity irrigation wells should ensure the owner has obtained a withdrawal registration and that the proposed use has passed the screening tool for environmental impacts. EGLE’s Water Resources Division also oversees this program jointly with MDARD. In short, any large groundwater withdrawal in Michigan triggers additional regulatory oversight to protect water resources.

In addition to the above, Michigan has a Well Drilling Advisory Board (composed of industry and government representatives) originally instituted under the Groundwater Quality Control Act. This board advises on drilling regulations and licensing. There are also industry groups like the Michigan Ground Water Association (MGWA) which drillers often join for continuing education and updates. But the day-to-day rules and contacts will typically involve the local health department and EGLE’s well program staff.

Well Logs, Forms, and Documentation for Michigan Drillers

Accurate documentation is not just a formality – it’s the law and a valuable practice. Michigan provides official forms that must be used or adhered to for well construction and decommissioning records. The cornerstone document is the Water Well and Pump Record (often simply called the “well log”). This multi-section form captures all the details of a newly drilled well: owner and location, well depth, diameter, drilling method, geologic strata encountered (with thickness and depth of each layer), casing and screen specifications, grouting, pump installation details, and well yield and static water level readings. Drillers must complete this record for each well and submit it within 60 days of completion, as mentioned earlier. In practice, most drilling contractors input the data into the Wellogic online system which then fulfills the submission requirement and stores the data in the state database. It’s wise for drillers to also provide a copy to the customer and keep their own copy for reference.

Michigan’s Wellogic database is a powerful tool for professionals – it contains hundreds of thousands of well records statewide and can be searched by location. Before drilling a new well, contractors frequently check Wellogic or the Well Viewer GIS map for logs of nearby existing wells. These logs can reveal how deep the aquifer is and what materials (sand, clay, rock) were encountered, helping in planning the new well. (For example, if nearby logs show bedrock at 120 feet and a productive sand aquifer above that, the driller might aim for a similar target depth.) EGLE provides public access to Wellogic for this purpose, making it a part of due diligence for drilling projects.

Another important form is the Abandoned Water Well Plugging Record. Whenever a well is permanently abandoned (for instance, a old well is replaced by a new one), Michigan’s code requires it to be properly plugged (sealed) and a record of the plugging to be filed. Typically, the same registered contractor who plugs the well will fill out this form, detailing how the well was sealed (what materials were used, at what depths). Plugging is usually done with neat cement or bentonite grout from bottom to top to eliminate it as a contamination pathway. The importance of plugging abandoned wells is underscored by the state – it protects aquifers from surface pollutants and prevents inter-aquifer mixing. Michigan EGLE has published a guidance manual and fact sheets on abandoned well plugging, which drillers should follow closely. Homeowners can legally plug their own private well in Michigan (if not serving others), but they often hire contractors; in all cases a plugging record must be submitted to the health department.

Drillers should also be aware of documentation for pump installations. If a pump is installed at a later date by a different contractor, a pump installation record is required. Michigan allows a registered well driller to also perform pump work without a separate license (and vice versa a pump installer can do well drilling if properly registered). In any case, a record of the pump (make, model, depth set, etc.) either gets included on the well record or on a separate pump record submitted within 60 days. All of these forms (well construction, pump installation, plugging) are available through EGLE’s forms portal or the Water Well Construction website.

Utility Clearance: “Call 811” Before You Drill

One absolutely critical step before any drilling in Michigan is to ensure all underground utilities are located and marked. Michigan state law (Public Act 174 of 2013) requires that you contact the MISS DIG 811 system before excavation, which includes drilling a well. MISS DIG 811 is Michigan’s one-call utility notification center. By either calling 811 or using their online ticket system, drillers can request utility locates. Within 3 business days, utility operators (electric, gas, water, telecom, etc.) will come mark the locations of buried lines on the property. It is illegal to start drilling before the locate period expires and the site is marked.

Hitting a buried gas line or power line with a drill rig auger or bit could be catastrophic for safety, and also carries heavy penalties. Thus, professional drillers in Michigan incorporate MISS DIG notification as a standard step in their scheduling. Once the ticket is cleared and utilities are marked or cleared, the driller should still proceed with caution, hand-digging when near marked lines (state law requires hand digging within 4 feet of a marked utility to expose it). The MISS DIG system is free to use and protects both the driller and the property owner from potentially dangerous accidents. Even on rural sites, never assume there are no utilities – always call 811 beforehand. Aside from utilities, it’s also prudent to verify there are no nearby pipelines or other subsurface structures; MISS DIG will coordinate with all member utilities, which includes virtually all major companies in Michigan.

In summary, “Call before you dig” applies to well drilling just as it does to any construction excavation. Document the MISS DIG ticket number and keep it on file for the project. Additionally, be mindful of any private utilities that MISS DIG might not mark (like a privately-installed electric line to a barn, or a septic tank electric conduit) – those should be located by the owner if possible. Safe drilling practices require knowing what’s below the drill site.

Other Regulations and Useful Facts for Michigan Drillers

Contractor Licensing (Registration): Michigan does not have an individual “license exam” per se for well drillers in the way some states do, but it requires all water well drilling contractors to be registered with the state. The Groundwater Quality Control Act of 1966 introduced the requirement for Contractor Registration and established a Well Drilling Advisory Board. Today, to operate legally, a drilling business must obtain a certificate of registration through EGLE (this is often achieved by having an experienced driller take an exam administered by the state and paying the registration fee). Registered well drilling contractors are issued an identification number (which appears on well records). They must renew this registration periodically (usually every 3 years) and are subject to continuing education requirements. Similarly, pump installers are registered. Notably, Michigan’s rules allow a single registered contractor to perform both drilling and pump installation work, simplifying the credentialing. Always ensure your registration is up-to-date and that your business name, addresses, and rig information are on file with EGLE – the state can take enforcement action (including fines or stop-work orders) against unregistered individuals drilling wells.

Well Construction Code Highlights: Part 127’s administrative rules detail how wells must be constructed. Key points include: minimum casing thickness and specifications; required casing depth into firm formations; annular space grouting (Michigan typically requires the annulus to be grouted with bentonite or cement from the bottom of the casing up to a certain height to seal off surface water entry – usually a minimum of 5 or 10 feet into the casing or up to ground level, depending on well type); and use of approved materials (e.g. NSF-certified plastic well casing). Michigan also has special rules for flowing artesian wells – drillers must install a flow control device or a spool to contain artesian pressure, and fully grout the casing to prevent leakage around the outside. There are provisions for variances if unusual situations arise, but these must be granted by health officials case-by-case. It’s crucial to follow the well code not just for legal compliance but to ensure longevity and safety of the well (for example, proper grouting prevents contamination and flowing well erosion).

Water Quality Testing and Reporting: When a new well is put into service for drinking, the owner (or often the driller on their behalf) must have the water tested for coliform bacteria and sometimes other parameters as required by the local health department. Michigan does not universally require a full chemical analysis for private wells, but many health departments will at least advise testing for nitrate, arsenic (which can be regionally elevated), and any local contaminants of concern. For public supply wells, a full suite of tests (inorganic, organic, radiological) is required under the Safe Drinking Water Act rules. As a driller, it’s good practice to inform your clients of the importance of water testing. The initial bacteria test is needed to get final approval of the well; beyond that, homeowners should test their well water periodically. MDHHS and EGLE provide guidance on recommended testing schedules.

Large Capacity Wells and Water Withdrawal Law: As mentioned, if you are drilling a high-capacity well (e.g. for irrigation, large industrial use, etc.), Michigan’s Water Withdrawal law comes into play. Before drilling such a well, the owner must use the Water Withdrawal Assessment Tool (WWAT) to get approval. The tool evaluates whether the proposed withdrawal will negatively impact nearby streams or aquifers. If the tool indicates potential adverse impact, a site-specific review is required and EGLE may deny or condition the withdrawal. Practically, drillers should ensure their clients have completed this process prior to drilling a high-capacity well. If a well with capacity ≥70 GPM is drilled, it must be registered with the state within 90 days of completion. Michigan is serious about managing groundwater in the context of Great Lakes stewardship, so failing to register a large well or exceeding a withdrawal that was not authorized can lead to enforcement and even legal penalties. On the flip side, once registered and approved, these wells must be monitored and annual water use reported (for agricultural wells, reporting to MDARD; for others, to EGLE). Drillers may want to guide clients through this or at least make them aware, as part of customer service.

Enforcement and Compliance: Michigan’s well program conducts oversight to ensure contractors follow the rules. If a well is found to be constructed improperly (violating the code), EGLE and local health departments can issue violation notices. Common issues might include insufficient grouting, not achieving required casing depth, or not maintaining isolation distances. There is a tiered approach to enforcement – from warning letters and correction orders to, in serious cases, suspension or revocation of the driller’s registration. Also, Michigan has an Administrative Complaints process for formal actions against contractors (EGLE publishes an annual list of any disciplinary actions). Staying in compliance not only avoids these issues but also protects your reputation. The state offers many training materials (including YouTube video modules on proper well construction hosted by EGLE). It’s wise for even experienced drillers to refresh knowledge periodically and for new drillers to take advantage of these resources.

Additional Resources: For further detailed reading, drillers can refer to the State of Michigan Water Well Manual, which is a comprehensive 145-page guidance document covering everything from hydrogeology to well drilling methods and the regulatory framework. Another useful document is the Michigan “Flowing Well Handbook,” which provides guidance on handling artesian wells. The Michigan Geological Survey and USGS have published numerous reports characterizing groundwater in different regions of Michigan – these can be found in libraries or online (e.g., USGS Water-Supply Papers, Hydrologic Atlases). DrillerDB’s platform may also host many of these references for quick access. Finally, the MGWA (Michigan Ground Water Association) holds conferences and training which are great for networking with peers and staying current on any changes in state law or new drilling technologies suited for Michigan conditions.

By understanding Michigan’s unique geological conditions and regulatory requirements, water well professionals can ensure they drill safe, productive wells in compliance with the law. Whether it’s navigating a tricky glacial clay layer or filling out the proper paperwork, the knowledge outlined above serves as a foundation for successful drilling operations in the Great Lakes State.