Due diligence checklist

Print it, or copy it per parcel. Nothing gets waived without a written answer.

Companion to 01-buyers-playbook.md.

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A. Desk screen (free, do before touring)

• Parcel ID, acreage, legal description pulled from county land records
• Current and prior owners, ownership duration, transfer history
• Tax assessment history, and any delinquency
• Zoning district and overlay districts confirmed on county GIS
• Shoreland zoningshoreland zoningCounty rules controlling what you can build within 1,000 feet of a lake or 300 feet of a river. They set your setbacks, your buffer, and how much of the lot you can pave. applies? Setback and buffer requirements noted
• Water body identified and navigabilitynavigable in factWisconsin's test for whether a waterway is public. Roughly: can a small recreational boat float on it on a regularly recurring basis. A lot of modest creeks qualify. status confirmed via DNR
• Watershed identified, and whether the parcel is inside the Great Lakes basin
• FEMA flood zone checked, panel number recorded
• DNR Wetland Inventory checked, mapped wetlands noted
• NRCS Web Soil Survey: soil types, septic suitability, drainage class
• BRRTSBRRTSWisconsin DNR's public database of contaminated and cleanup sites. Search it before you buy anything, and search upgradient of the parcel too. search: contaminated sites on parcel and within 1 mile
• DNR PFASPFASThe "forever chemicals" from firefighting foam and industrial processes. They do not break down, treatment is expensive and permanent, and standards keep tightening. Never in a standard water test unless you ask for it by name. data viewer checked for the area
• County nitratenitrateFertilizer and manure that has leached into groundwater. Above 10 milligrams per liter it is a health risk, especially for infants, and you cannot fix your neighbor's fields. testing summary reviewed
• DNR high capacity wellhigh capacity wellIn Wisconsin, a well (or all wells on 1 property combined) capable of pumping 100,000 gallons a day or more. These need DNR approval. An ordinary house well does not. search within 2 miles, count and volumes recorded
• WGNHS county geology reviewed, aquiferaquiferUnderground rock or sand with water in the spaces between the grains. It is not an underground lake. Water seeps through it slowly, often only feet per year. identified
• Nearby well construction reports pulled, typical depth and yield noted
• Topographic map reviewed, upgradient land uses identified
• Aerial imagery history reviewed (historic ag, fill, structures, ponds)

B. Contract stage (before you sign)

• Wisconsin real estate attorney engaged
• Real Estate Condition Report obtained and read, well and septic sections flagged
• Water quality contingencycontingencyA condition written into a purchase contract that lets you walk away if something checks out badly. Drafting these well costs an hour of attorney time and is the cheapest protection in the whole process. drafted, with named test panel and thresholds
• Well yield contingencycontingencyA condition written into a purchase contract that lets you walk away if something checks out badly. Drafting these well costs an hour of attorney time and is the cheapest protection in the whole process. drafted, with gpm, duration, and recovery criteria
• Survey and OHWMordinary high water markThe physical line on a shoreline showing where water regularly reaches. On a Wisconsin lake your private property stops there and the state owns the bed below it. The DNR decides where the line is, not your deed. contingency drafted
• Zoning and intended use contingency drafted
• Access and easementeasementA recorded legal right for someone else to use part of your land, such as a driveway crossing or utility access. It survives the sale and binds you. contingency drafted
• Title contingency includes water-related encumbrancesencumbranceAnything recorded against a property that limits what the owner can do: easements, liens, deed restrictions, mineral reservations. explicitly
• Inspection period long enough for lab turnaround (PFASPFASThe "forever chemicals" from firefighting foam and industrial processes. They do not break down, treatment is expensive and permanent, and standards keep tightening. Never in a standard water test unless you ask for it by name. can take 3 to 6 weeks)
• Right to enter for testing and drilling granted in writing

C. Title and boundaries

• Title commitment reviewed by attorney
• All easementseasementA recorded legal right for someone else to use part of your land, such as a driveway crossing or utility access. It survives the sale and binds you. identified, mapped, and understood
• Any prior conveyance of riparianriparianThe eastern US rule, and Wisconsin's rule. If your land touches a lake or stream, you get reasonable use of that water, shared with everyone else whose land touches it. The rights come with the land and generally cannot be sold separately from it. access or lake access to third parties
• Mineral rights: severed or intact
• Any recorded well agreement, shared well, or water use agreement
• Any conservation easement, agricultural easement, or deed restriction
• Boundary survey completed by a licensed WI surveyor
• OHWMordinary high water markThe physical line on a shoreline showing where water regularly reaches. On a Wisconsin lake your private property stops there and the state owns the bed below it. The DNR decides where the line is, not your deed. located and staked (DNR determines this line, a surveyor alone can’t)
• Bed ownership understood: lake bed is state-owned below the OHWM, stream bed is generally yours to the center thread
• Buildable envelope calculated from OHWM after all setbacks
• RiparianriparianThe eastern US rule, and Wisconsin's rule. If your land touches a lake or stream, you get reasonable use of that water, shared with everyone else whose land touches it. The rights come with the land and generally cannot be sold separately from it. frontage measured, and lot-width-to-frontage rules checked
• KeyholekeyholeLocal rules that stop a developer from running many back-lot households through 1 narrow strip of lake frontage. / funnelingkeyholeLocal rules that stop a developer from running many back-lot households through 1 narrow strip of lake frontage. ordinance checked with the county

D. The well

• Well construction report located in DNR records (or absence documented)
• Well depth, casing depth, casing material, grouting recorded
• AquiferaquiferUnderground rock or sand with water in the spaces between the grains. It is not an underground lake. Water seeps through it slowly, often only feet per year. / formation the well draws from identified
• Well age, and whether it meets current NR 812NR 812Wisconsin's well construction code. Wells drilled decades ago often do not meet it, especially on casing depth and grouting. construction standards
• Static water levelstatic water levelHow far down the water sits in a well when nothing is pumping. Tracking this over decades is the best single indicator of whether an aquifer is in trouble. measured today
• Historic static water levelstatic water levelHow far down the water sits in a well when nothing is pumping. Tracking this over decades is the best single indicator of whether an aquifer is in trouble. compared, trend assessed
• Sustained yield test performed, gpm and drawdowndrawdownHow far the water level drops while a pump is running. and recovery recorded
• Pump age, type, depth, and condition
• Pressure tank, wiring, and wellhead condition inspected
• Wellhead location relative to septic, barnyard, fuel tanks, road salt storage
• Any abandoned or unused wells on the parcel located (these are direct contamination conduits and must be properly filled and sealed)
• Would a new well be permittable here, and at what depth and cost

E. Water quality testing

Use a Wisconsin certified lab. Ask for PFAS and pesticides by name, they’re never in a standard panel.

• Total coliform bacteria and E. coli
• NitratenitrateFertilizer and manure that has leached into groundwater. Above 10 milligrams per liter it is a health risk, especially for infants, and you cannot fix your neighbor's fields. as N (health standard 10 mg/L)
• Arsenic (a known problem in eastern and northeastern WI)
• Lead and copper
• Manganese
• Iron, hardness, pH, total dissolved solids
• RadiumradiumA naturally radioactive element in southeastern Wisconsin's deep sandstone aquifer. It is what pushed Waukesha off its wells and onto Lake Michigan water. and gross alpha (deep sandstone aquifer, southeast WI; this is exactly what forced Waukesha off groundwater)
• Fluoride
• Chloride and sodium (road salt and septic indicator)
• PFAS panel (EPA method 537.1 or 533)
• Pesticides and herbicides, including atrazine and metabolites, if ag adjacent
• VOCs, if any industrial or fuel history
• Sulfate, if livestock history
• Results compared against Wisconsin NR 809 standards and health advisory levels
• Second round of sampling after a rain event, if any result is borderline

F. Surface water and shoreline

• Water body’s DNR classification and impairment status (303(d)303(d)The federal list of waters too polluted to meet standards. If the lake you are buying on is on it, find out why before you close. list)
• Water clarity, algae, and invasive species history for the lake
• Lake association or management district exists? Dues and assessments
• Existing pier: permitted, conforming, and transferable
• Shoreline erosion history, and any riprap or shoreline structures and their permit status
• Lake level history, and Lake Michigan level cycle if applicable
• Any dam upstream or downstream, and who owns and maintains it
• Chapter 30 permitChapter 30 permitWisconsin DNR permission to build or change anything on navigable water: piers, dredging, rock riprap, or grading near the shoreline. history for the parcel
• Any prior DNR enforcement action on the parcel

G. Neighbors and watershed

• All high capacity wellshigh capacity wellIn Wisconsin, a well (or all wells on 1 property combined) capable of pumping 100,000 gallons a day or more. These need DNR approval. An ordinary house well does not. within 2 miles: owner, permitted volume, use
• Any pending high capacity well applications in the area
• CAFOsCAFOA large industrial livestock operation. In Wisconsin water disputes it is usually the source of the nitrate and bacteria showing up in neighbors' wells. within 5 miles, and manure spreading fields upgradient
• Landfills, quarries, gravel pits, or mines nearby
• Industrial dischargers (WPDESWPDESWisconsin's permit for discharging pollutants into water. The permit list tells you who is legally dumping upstream of you. permit holders) in the watershed
• Municipal wastewater treatment plant discharge points upstream
• Any proposed data center, industrial park, or large development in the area
• Agricultural land upgradient, crop type and irrigation practice
• Rate of development in the township over the last 10 years

H. Regulatory and future risk

• County comprehensive plan reviewed for the area’s future land use designation
• Any pending rezoning or ordinance amendment affecting the parcel
• Any pending state legislation on wells, shoreland, or groundwater
• Confirm intended use in writing with the county zoning administrator
• If planning a large withdrawal, confirm high capacity well permitting feasibility with DNR early
• Sanitary district or municipal water service expansion plans (a future mandatory hookup changes your economics)
• Special assessments planned for the area

I. Closing and after

• Every contingency satisfied in writing before waiver
• Seller warranties on well and septic negotiated to survive closing
• All test results, reports, and permits filed in the property folder
• Post-closing baseline water test performed and archived (this is your evidence if a neighbor contaminates the aquifer later)
• Well registered with the county
• Any abandoned wells properly filled and sealed by a licensed driller
• Annual reminder set: bacteria and nitrate test
• 3 to 5 year reminder set: full panel including PFAS
• Static water level logged annually in a spreadsheet, so you build your own trend line

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The 6 questions that decide the deal

If you only get 6 answers, get these.

1. Where exactly is the ordinary high water mark, and what’s my buildable envelope from it?
2. What does the well produce under a sustained load, and what’s the aquifer’s 20 year water level trend?
3. What’s in the water, including PFAS, arsenic, radiumradiumA naturally radioactive element in southeastern Wisconsin's deep sandstone aquifer. It is what pushed Waukesha off its wells and onto Lake Michigan water., and nitrate?
4. Who else pumps this aquifer within 2 miles, and how much?
5. What’s upgradient of me, and what’s it going to be in 10 years?
6. Does the county zoning administrator confirm in writing that my intended use is allowed?