Private well guide

Well Water in Ohio: Testing, Rules, Labs and Licensed Contractors

744,406 households in Ohio get their water from a private well. Here is what the state requires, where to get it tested, and who is licensed to work on it.

Find a certified labLicensed contractorsPick my county
584Licensed contractorschecked against state records
39Certified labsfrom the state certified list
86Counties covered
744,406Households on wells18% of households (est.)

More than 700,000 Ohio households drink from a private well, and the state handles them differently from most of its neighbors: the rules are written in Columbus, but the permit, the inspection and the first water sample all come from your county health district. Once that sample passes, nobody tests the water again unless you do.

Who does what in Ohio

The Ohio Department of Health writes the private water system rules (OAC 3701-28) and registers every contractor who drills wells, sets pumps, installs treatment or seals old wells. Local health districts do the field work: they issue the permit before a well is drilled or altered, inspect it when it is finished, and collect the water sample that decides whether the system is approved. Well logs go to a third agency, the Ohio Department of Natural Resources, which has kept driller reports since 1948 and puts them online by county and address.

The permit, the inspection and the one required test

Before any new well, replacement well or major alteration, the owner or contractor applies to the health district for a permit. When the work is done the owner calls the district back for a final inspection. A sanitarian checks the casing, cap, grout and pitless adapter against the rule, then collects the sample: total coliform, E. coli and nitrate. For a well without continuous disinfection the result must show 4 or fewer coliform per 100 mL and no E. coli. A failed sample means shocking the well and resampling until it passes. Ohio has no test requirement when a house is sold, but nearly every district will run a real-estate evaluation on request, and FHA, VA and USDA loans usually require one.

At a glance

Water test for a new wellRequired

Under OAC 3701-28 a permit from the local health district is required before a well is drilled or altered. When the work is done, the owner asks the health district for the final inspection, and a sanitarian collects the water sample: total coliform, E. coli and nitrate. The system is approved only when the sample passes (4 or fewer total coliform per 100 mL and no E. coli for a well without continuous disinfection).

Water test when a home is soldNot required statewide

No statewide requirement. Most local health districts offer a real-estate evaluation of the well on request (a visual inspection plus a bacteria and nitrate sample), and some lenders ask for one. Ask the county health district for its fee and turnaround.

What the state recommends

ODH recommends a total coliform and nitrate test every year, and every time the water changes in taste, color or smell, after flooding, or after any work on the well or pump. Add arsenic, iron and manganese, hardness and sulfate at least once, and PFAS or methane where local conditions call for it.

Free or low-cost testingAvailable

No statewide free program. Several county health districts run their own labs (Erie, Logan, Mahoning, Canton City among them) and sell bacteria and nitrate tests at cost; others sell bottles from a certified lab. OSU Extension fact sheet AEX-315 lists labs that accept samples from homeowners.

What Ohio wells are known for

Two problems follow geology across the state. In the glaciated northwest and the central counties, wells drawing from buried sand and gravel can carry naturally occurring arsenic, and the same farm country puts nitrate into shallow wells. East and south of the glacial line, wells in shale and coal-measure sandstone bring up iron, manganese, sulfate and the rotten-egg smell of hydrogen sulfide, sometimes with radium or uranium. Wells near oil and gas fields in the eastern counties should be checked for methane. Hard water is nearly universal. ODH asks for a bacteria and nitrate test every year, and a one-time look at arsenic, metals and hardness tells you which treatment, if any, is worth buying.

Certified labs and county health district labs

Ohio EPA certifies laboratories for public drinking water, and the same labs run private well samples. Several health districts operate their own small labs for bacteria and nitrate, which is usually the cheapest route for a yearly check. The list below marks the labs that OSU Extension confirms will take a homeowner sample; for the rest, call first and ask about bottles, hold times and price.

39 certified labs

See all 39 certified labs in Ohio

ODH-registered contractors

Every private water systems contractor in Ohio must register with ODH each calendar year and declare which work they do: well construction, pump installation, water treatment, well sealing, springs, cisterns or ponds. The profiles below come from the ODH registration report and show each contractor’s registration number and declared activities, plus out-of-state drillers who are registered to work in Ohio.

584 licensed contractors

See all 584 licensed contractors in Ohio

By county

The share of homes on wells runs from under 5% in Cuyahoga, Hamilton and Franklin to more than half in Geauga, Holmes, Carroll and Morrow. Each county page carries its well population, the nearest certified labs and the registered contractors based there.

Ohio well water questions

Do I need a permit to drill a well in Ohio?

Yes. The local health district issues a private water system permit before a well is drilled, deepened or replaced, and most districts also require an alteration permit for work such as replacing a pump or adding treatment, so check with yours. The contractor doing the work must be registered with ODH for that activity.

Is a water test required when I sell my house?

No statewide test is required. Health districts offer a real-estate evaluation on request, typically a visual inspection plus a bacteria and nitrate sample, and government-backed loans usually ask for one.

How do I find my well log?

Search the ODNR well log database by county, township or address. Logs since 1948 show the depth, the casing, the static water level and the driller. Wells drilled before that, or never reported, will not be on file.

Where is arsenic a problem in Ohio?

Mostly in the glacial aquifers of northwest and central Ohio, where it can exceed the 10 ppb standard in a meaningful share of wells. A one-time arsenic test is cheap, and a reverse osmosis unit at the kitchen tap is the usual fix.