Drilling in Wisconsin - A Comprehensive Guide

Overview of Wisconsin’s Geological Conditions and Aquifers

Wisconsin’s groundwater is drawn from several distinct aquifer systems determined by the state’s geology. According to the Wisconsin Geological and Natural History Survey and the Department of Natural Resources (DNR), there are four principal aquifers in Wisconsin: the sand and gravel aquifer, the eastern dolomite aquifer, the sandstone and dolomite aquifer, and the crystalline bedrock aquifer. These aquifers correspond to major geologic units and vary in depth, composition, and yield across the state. Table 1 below summarizes key characteristics of Wisconsin’s aquifers:

The sand and gravel aquifer (glacial drift) lies at the surface across most of Wisconsin, so it often provides the first encountered groundwater (hence many rural driven-point wells tap shallow sand layers). However, because it is unconfined at the land surface, this aquifer is highly susceptible to any surface pollutants that infiltrate downward. In contrast, the bedrock aquifers (dolomite and sandstone) are usually confined by layers of shale or clay in many areas, which can protect the water but also means wells must be drilled deeper to reach them. For example, in eastern Wisconsin the Maquoketa shale forms a major confining unit between the shallow dolomite and the deep sandstone aquifer. In those eastern counties, a driller might encounter ~50 feet of dolomite, then shale, before reaching the high-yield sandstone layers hundreds of feet down. By comparison, in much of central and western Wisconsin, the sandstone and dolomite aquifer is closer to the surface (sometimes directly under glacial deposits), making well depths there moderate.

Groundwater availability is generally good statewide – even the crystalline rock in the north can supply domestic wells if enough fractures are intercepted. As one Wisconsin DNR guide puts it, “You can drill a hole just about anywhere in Wisconsin and find water”. The main differences are in how much water is available and how vulnerable it is to contamination. Drillers should be aware of regional conditions: for instance, the karstic dolomite in Door County demands extra caution to prevent surface contaminants from rapidly entering the aquifer, and the deep sandstone wells in the southeast may require understanding of long-term drawdown trends. Overall, knowledge of the local geology – including whether you’re drilling in unconsolidated glacial deposits, shallow fractured bedrock, or deep sandstone – is critical for successful well construction in Wisconsin.

Well Construction Permitting Requirements in Wisconsin

Wisconsin has specific permitting and notification requirements for constructing water wells, administered primarily by the DNR. Before drilling any new water well, the property owner (or driller on their behalf) must provide advance notice to the DNR. Wisconsin law requires obtaining a Well Construction Notification for any new private well (i.e. wells not classified as high-capacity or public systems). In practice, this means:

• Hire a licensed water well driller. All wells must be constructed by a DNR-licensed well driller (or a registered rig operator under a licensed driller’s supervision). The only exception is that a private property owner may construct a well on their own property, but they still must follow all code requirements. (Driven-point sand point wells also do not require the driller to hold a license, but they still require notification and code compliance.)
• Obtain a Well Construction Notification Number prior to starting drilling. This is essentially a state permit/notification for the new well. The notification can be obtained online (via the DNR’s GoWild licensing system) or at any DNR license sales location, for a fee of $50.50. Once obtained, the notification number must be recorded and a copy of the DNR receipt should be kept on site. This requirement applies to both drilled wells and driven-point wells.
• Exceptions: If the well is a high capacity well (see below) or a well that otherwise requires separate DNR approval (e.g. public community wells regulated under NR 811), then the standard notification process is waived in favor of that specific approval process. Also, reconstruction of an existing well (e.g. deepening or installing a liner in a well) typically does not require a new notification if the well already exists.

After obtaining the notification, the driller can proceed with construction in compliance with state well construction standards (Wis. Admin. Code NR 812 – the well and pump code). It’s important to note that some local jurisdictions have their own permit requirements in addition to the state notification. Under DNR rules (NR 845), counties can adopt ordinances to administer private well regulations locally. In counties with DNR-approved well programs, a County Well Location Permit must be obtained before drilling. The application is made using the official County/State Well Location Permit Application (Form 3300-076), and it must be submitted to the county at least two working days prior to construction0. The county permit (often handled by the county health or environmental health department) verifies that the proposed well location meets all setback requirements from septic systems, fuel storage, etc., per NR 812. If a county well permit is required, proof of that permit would be in addition to the DNR notification number.

High-Capacity Wells: Wisconsin defines a “high capacity well” as one that, alone or in combination with other wells on the property, can withdraw more than 100,000 gallons per day (approximately 70 gallons per minute). Agricultural irrigation wells, industrial or municipal water supply wells often meet this threshold. High-cap wells are subject to a more involved permitting process: prior DNR approval is required before construction. The well owner (applicant) must submit a High Capacity Well Application along with a $500 fee to the DNR. The DNR will conduct a review to ensure the proposed high-capacity well will not cause unacceptable environmental impacts (such as excessive drawdown of nearby streams, interference with other wells, or water quality concerns). Only after receiving written approval can the driller construct a high-capacity well. (Certain replacements or reconstructions of existing high-cap wells may not need full re-approval under recent law changes, but those situations are handled on a case-by-case basis.)

In summary, for most routine private wells, the key steps are hiring a licensed driller and obtaining the DNR well notification number before drilling. Always check if your project location falls under any county’s well ordinance; if so, secure the county permit. For large water-use wells, budget additional time for the state’s high capacity well permit process. The DNR provides guidance and application forms for all these steps on their website.

Key State Agencies Involved in Groundwater and Well Regulation

Wisconsin Department of Natural Resources (DNR) – The DNR is the primary regulatory authority overseeing water well construction, well operation, and groundwater protection in the state. The Drinking Water & Groundwater Program within DNR administers Wisconsin’s well code (NR 812) and licensing of well professionals (NR 146). The DNR ensures that wells are properly located, constructed, and maintained to protect groundwater quality and public health. This includes reviewing well construction reports, conducting inspections, and enforcing well construction standards. Wisconsin’s private well regulations derive from state statutes (e.g. Chapter 280, Wis. Stats., “Pure Drinking Water”) which authorize DNR to set standards for well construction and require notification/permits. The DNR also handles approvals for high capacity wells and public water supply wells, as noted above. For well drillers, the DNR is essentially the go-to agency for guidance and compliance – they provide online resources, technical support, and compliance assistance (e.g., the DNR’s “Well Driller Viewer” mapping tool helps drillers identify special well construction requirements or setback zones in a given area). In addition, the DNR manages the statewide database of well records and water quality data.

Wisconsin Geological and Natural History Survey (WGNHS) – The WGNHS is a state-supported scientific agency (part of UW–Madison Division of Extension) that conducts research on Wisconsin’s geology and groundwater. While not a regulatory body, WGNHS plays a crucial role in understanding aquifer systems and providing data to both regulators and drillers. They maintain extensive records of well logs, geological samples, and aquifer studies. In fact, WGNHS publications contain maps and cross-sections of Wisconsin’s aquifers that are useful for drillers planning a well. For example, WGNHS has delineated nine regional hydrogeologic districts in Wisconsin, each with characteristic aquifer conditions. Drillers and consultants often refer to WGNHS reports for information on expected depths to bedrock or aquifer type in a given area. The Survey also cooperates with the DNR and USGS on groundwater monitoring. Many well logs (well construction reports) collected by DNR are also available through WGNHS or linked resources. As one DNR document notes, the WGNHS “has maps, well construction reports and other information on aquifers and geology” in Wisconsin. In short, WGNHS is an authoritative resource for geological context, though enforcement of well regulations remains with DNR.

Other Agencies: Some other entities have supporting roles. The Wisconsin Department of Health Services (DHS) works with DNR on drinking water quality standards (e.g., setting health-based limits for contaminants in private wells). Local County Health Departments (or Land Conservation Departments) in counties that have adopted well ordinances (under NR 845) act as the DNR’s local agents in permitting and inspecting private wells. These county officials issue the county well location permits and ensure compliance with NR 812 at the local level. The Public Service Commission of Wisconsin (PSC) oversees enforcement of the state’s “One Call” utility damage prevention law (see below), which intersects with well drilling when excavation is involved. Additionally, the PSC regulates municipal water utilities (some of which operate high-capacity wells), although the construction of the wells themselves is still under DNR’s purview. Finally, Wisconsin’s Groundwater Coordinating Council (GCC) is an inter-agency group (including DNR, WGNHS, USGS, DHS, etc.) that facilitates research and policy coordination on groundwater issues0 – while not directly involved in permitting, the GCC’s work often results in resources or guidelines beneficial to those in the water well industry.

Official Well Log Forms and Documentation for Drillers

Keeping proper records is a vital part of well drilling in Wisconsin. The state requires that upon completion of a new well, the driller must file a Well Construction Report (WCR) – commonly called the “well log” – detailing the well’s location, depth, geology encountered, construction details (casing, screen, grouting), and initial water yield. A copy of this report must be provided to the well owner and to the DNR. In fact, the driller (or driven-point installer) is obligated to give the owner a well construction report within 30 days of finishing the well, and to submit the report to DNR’s online system in the same timeframe. These well logs become part of the public record and are invaluable for future drilling in the area.

The DNR maintains an online Well Records Search tool that allows drillers and researchers to retrieve existing well construction reports statewide. By entering a location or well ID, you can view the log of any well on file, which includes the depth to bedrock, water level, pump test yield, etc. This is often the first stop in site investigation – e.g., if you are going to drill a new well, you might search for nearby wells to get an idea of geology and aquifer depth. The database includes hundreds of thousands of well reports (all wells constructed since 1988 are indexed by location; older ones are indexed by township-range). Well construction reports are also downloadable as PDF files from that database.

For current drilling projects, here are some key forms and documentation drillers should be aware of:

• Well Location Permit Application (Form 3300-076) – as mentioned above, this is used in counties that require a well permit. The form can be obtained from the DNR website as a PDF (download here. It asks for details like the property owner, proposed well construction method, and a site plan. The form also includes fields for the county to document inspection results. Always check if the county where you’re drilling uses this permit system.
• Well Construction Report (WCR) – Wisconsin encourages online submission of WCRs via the DNR’s Online Well Construction Report System. Licensed drillers have access to this system (requires a WAMS ID login) to input well data directly. However, if needed, a paper WCR form can be used (the DNR can provide a blank form template on request). All WCRs eventually end up in the DNR’s well database. Remember that “well construction report” is synonymous with “well log” or “well record”.
• Well Filling & Sealing Report (Form 3300-005) – When an old well is abandoned (filled and sealed), a driller or pump installer must file this report to document proper decommissioning. It’s worth noting in case your project involves replacing a well; the old one must be sealed and reported. The official form is available on the DNR site.
• Pump Installation Report – Wisconsin also requires that new pump installations or replacements on a well be documented, typically by the licensed pump installer. These reports ensure the pump and pressure system meet code, but the forms are generally handled by pump installers (often the drilling contractor if they are dual-licensed).
• Water Quality Test Forms – After construction, the well must be sampled for bacteria and nitrate. Drillers need to arrange for a certified lab test and submit results. The DNR provides forms (and an electronic reporting system) for transmitting initial water sample results. For example, there is a “Pump Work / Water Test” form (Form 3300-265) used when reporting that initial bacteria/nitrate test after constructing a well. The test results must be provided to the well owner within 10 days of receiving them and also sent to DNR.

All official DNR forms related to well construction and groundwater can be found on the DNR’s Groundwater Forms page0. This includes not only the construction and abandonment forms above, but also variance request forms, inspection checklists, etc. It’s good practice for drilling professionals to familiarize themselves with these documents. Using the correct forms and submitting them on time (and to the right agency) will keep you in compliance with state regulations and avoid project delays.

Utility Clearance: “Call Before You Dig” (811)

Before any drilling begins, Wisconsin law requires checking for underground utilities at the site. Well drilling often involves not just vertical boring but also excavation for well pits or trenching for water lines or electrical lines to the well, which can potentially hit buried utilities. Wisconsin’s one-call utility locating service is known as Diggers Hotline. By law (Wis. Stat. §182.0175, the “Damage Prevention” law), anyone excavating or drilling must notify Diggers Hotline at least three business days in advance. This notification triggers the utility companies to mark the location of any buried lines (electric, gas, water, telecom, etc.) on the property. Drillers should always initiate an 811 call (or use the online request at diggershotline.com) well before the rig arrives on site.

Diggers Hotline will coordinate with all relevant utilities. The law is comprehensive – “excavation” is defined to include drilling, augering, boring, and grading. There are safe digging rules to follow: once utilities are marked, maintain an 18-inch buffer zone around the markings and hand-dig if you must excavate within that buffer. Violating the one-call requirement can lead to penalties and liability if a line is struck. More importantly, contacting 811 protects the safety of your crew and the public. Hitting a gas line or electric cable with a well drill could be catastrophic. Therefore, from a practical standpoint, professional drillers in Wisconsin incorporate the 811 call into their standard operating procedure for every job. Diggers Hotline operates 24/7 and the service is free; you just need to plan ahead for the 3-day notice.

One special consideration: if you are drilling in a rural area and also installing a grounding electrode or anode (for cathodic protection) as part of the well system, those activities also fall under the 811 notice. Even pounding a grounding rod could hit something unexpected. In summary, always “know what’s below” – call 811 before you drill.

Additional Regulations and Best Practices for Wisconsin Drillers

Beyond permitting, Wisconsin has a number of other regulations and guidelines that water well drillers must follow. Here are a few key points to keep in mind when operating in the state:

• Well Driller and Pump Installer Licensing: All individuals or firms engaging in well construction or pump installation must be licensed by the DNR (or working under the supervision of someone who is licensed). The licensing requirements are outlined in NR 146, Wis. Admin. Code. To become a licensed Well Driller in Wisconsin, one must pass an exam and meet experience or education criteria, and then maintain continuing education credits for annual renewal. The DNR maintains directories of currently licensed well drillers and pump installers on its website. Working without the proper license can result in fines and project shutdowns. Note that property owners may install their own well or pump without a license on their own property, but if they do so, they are held to the same construction standards and must still file the well report and water samples. In practice, almost all drilled wells are done by professional licensed contractors, given the complexity of the work.
• Construction Standards (NR 812): Wisconsin’s well code (NR 812) is quite detailed. It specifies minimum casing depths, grouting requirements, pump installation standards, and separation distances from contamination sources. For example, a new drilled well in an unconsolidated sand aquifer must have casing extending at least 25 feet below the ground surface and 10 feet into firm bedrock or specific geological strata if applicable. There are many specific rules: a well must be a set distance from septic systems (e.g. 25 feet from septic tanks, 50 feet from septic drainfields), farm animal yards, fuel storage tanks, landfills, etc., to reduce contamination risk. Drillers should ensure they are using up-to-date NR 812 requirements – the code is periodically revised, and recent changes (such as liner installation techniques or grouting materials) are published by DNR. The DNR provides handy reference sheets and fact sheets on common issues (for instance, there are fact sheets on well casing, liners, and screen installation on the DNR site).
• Special Well Casing Areas (Arsenic): Certain parts of Wisconsin have naturally occurring groundwater quality issues that require modified well construction. Notably, in the Fox River Valley (portions of Outagamie and Winnebago counties), there is an Arsenic Advisory Area due to arsenic-bearing minerals in the bedrock. The DNR has designated “Special Well Casing Depth Areas” in those counties where new wells must be constructed to more stringent standards to minimize arsenic contamination0. In practice, this means wells in those areas need deeper casing (through the entire problematic formation) and cement grouting to seal off the arsenic-producing layers. Drillers in Northeast Wisconsin should consult the DNR’s arsenic maps and specifications before drilling – failure to meet the special requirements could result in a well that is unsafe or not code-compliant. The DNR provides maps and updates for the arsenic advisory area online, and typically, the county will inform the driller if a site is within the special casing area when reviewing the well permit application.
• Well Development and Testing: After construction, Wisconsin requires that the new well be properly developed (by pumping, surging, etc.) to clear debris, and then a test pump installed to measure the well’s yield and drawdown. The driller should record the test pumping rate and water level drawdown on the well log. The minimum yield for a private domestic well is not explicitly stated in code (it’s generally whatever the homeowner needs), but the driller should ensure the well can sustain typical household use or advise the client if it cannot. For high capacity or public wells, more extensive aquifer testing may be mandated as part of the approval.
• Disinfection and Water Sampling: State code requires new wells to be disinfected upon completion (typically by chlorinating) and then flushed. A water sample must be collected after flushing and tested for coliform bacteria and nitrate as a basic indicator of water potability. The driller or pump installer is responsible for arranging this initial water test with a certified laboratory and providing the results to the owner and DNR. If the initial test shows contamination, the well may need corrective action (additional disinfection, well reconstruction or treatment) before use.
• Well Head Protection and Reporting: Once the well is finished, it should have a vermin-proof cap and stickup above grade (at least 12 inches above finished grade or 2 feet above any flood elevation) as required by code. The area around the casing should be sloped to drain surface water away. Drillers should advise owners on keeping the well area clean and not altering the well (for instance, not cutting off the casing or burying it – both are prohibited). Within 30 days, the driller must submit the Well Construction Report to DNR (if not already entered online) and, as mentioned, provide it to the owner. This report will assign a Wisconsin Unique Well Number (WUWN) to the new well for identification. Any time a driller encounters an unusual situation (such as needing a variance from code due to site conditions), they must get DNR approval and document it. Variances can be requested using DNR’s variance application forms, but they are typically limited to situations that still protect water quality.
• Well Abandonment: Though beyond the scope of drilling a new well, drillers should educate clients that any unused or “non-complying” wells on the property must be properly filled and sealed. State law requires abandonment of unused wells to prevent them from becoming direct pathways for contamination into aquifers. Licensed well drillers and pump installers are authorized to perform well abandonment, following NR 812 procedures (e.g., cleaning the well and pressure grouting it with bentonite or cement). The driller must then file the Well Filling & Sealing Report (Form 3300-005) with the DNR0. It’s good practice to address old wells during new well projects – often, property owners can coordinate abandonment of an old well at the time the new well is drilled.

By adhering to these regulations and best practices, well drilling professionals in Wisconsin can ensure they are providing safe, reliable water supplies while staying in compliance with the law. The DNR frequently updates guidance, so staying connected with industry groups like the Wisconsin Water Well Association and checking DNR “NewsBits” for drillers can help keep you informed of any rule changes or emerging issues (for example, changes in allowable casing materials, new PFAS sampling guidance, etc.). Ultimately, Wisconsin’s regulatory framework – from licensing, to permitting, to construction standards – is designed to protect both the drillers and the public by promoting sound well construction and groundwater stewardship.

Resources and References

The following authoritative sources provide further information and should be consulted for detailed requirements and data:

• Wisconsin Administrative Code NR 812 – Well Construction and Pump Installation – The full code detailing well construction standards.
• Wisconsin DNR Wells Program Website – Central hub for DNR information on well construction, including forms, guidance documents, and the Well Driller Viewer map.
• WGNHS “Major Ground-Water Units of Wisconsin” (Report ES028) – A detailed report describing Wisconsin’s aquifers and hydrogeologic regions, with maps and cross-sections.
• “Groundwater: Wisconsin’s Buried Treasure” – Wisconsin DNR Publication DG-055 – An educational booklet providing an overview of state groundwater resources, aquifer descriptions, and contamination issues (good background reading for understanding the hydrogeology).
• Diggers Hotline 811 – Wisconsin’s one-call utility locate service; website includes the legal requirements and an online request portal for excavators.
• Wisconsin Well Records Search (DNR Groundwater Data Viewer) – Online database to look up well logs (construction reports) and basic groundwater quality data by location.
• DNR Information for Well Drillers & Pump Installers – Webpage with links to codes, licensing info, and tools like the Well Driller Viewer and online reporting systems.
• DNR Arsenic in Groundwater – Special Well Casing Area Info – Details on the arsenic advisory area in NE Wisconsin, including maps of affected townships and construction requirements.

By leveraging these resources, drillers can stay informed and ensure that every well in Wisconsin is drilled safely, legally, and successfully.