In Wisconsin, pump and pressure-tank work on a drinking-water well, well drilling, filling and sealing old wells, and paid property-transfer well inspections must be done by people licensed by the Department of Natural Resources. The DNR publishes lists of licensed pump installers and well drillers you can search by county.
Updated October 2026
Which license does the job need?
| Job | Who can do it |
|---|---|
| Pump repair or replacement, pressure tank, pressure switch, pitless adapter | DNR-licensed pump installer (or a licensed driller) |
| New well, deepening a well | DNR-licensed well driller |
| Filling and sealing an unused well | DNR-licensed driller or pump installer |
| Paid well inspection for a home sale | DNR-licensed driller or pump installer, using DNR Form 3300-221 |
| House plumbing, water heater, water softener | Licensed plumber (a pump installer’s work stops at the pressure tank) |
How to use the DNR lists
- Open the DNR’s well contacts page and download the pump installer or well driller list.
- Filter by your county (Dane, Iowa, Green, Sauk and so on). Contractors often work in neighboring counties too.
- Call two or three and describe the symptom plainly: no water, low pressure, cycling, a failed water test.
- Ask them to confirm their license or registration number. Wisconsin requires licensed contractors to show it on their advertising, estimates and invoices.
Questions worth asking
- What’s your DNR license or registration number?
- Is there a service-call or diagnostic fee, and is it credited toward the repair?
- Can you give a written estimate before pulling the pump?
- Will you file the required DNR paperwork (for a new well, filling and sealing, or an inspection)?
- Do you have after-hours service if the house has no water?
- What’s the warranty on the pump and on the labor?
Before you call
A few details help the contractor size up the job: your well depth (from your well construction report), what the pressure gauge reads, when the problem started, and whether there was a storm or power outage. The symptom guide walks through safe checks.
Related
Sources: Wisconsin DNR well contacts and licensee lists; Wis. Admin. Code NR 146; DNR well licenses. Driftless Well Pump doesn’t recommend or refer specific contractors.
