Buying a House With a Well: Inspection and Water Testing Checklist

On this page

1. Is a well test or inspection required when you buy?
2. Step 1: Ask for the well’s paperwork
3. Step 2: Have the well inspected
4. Step 3: Test the water
5. Step 4: If results come back high
6. After you move in
7. Sources

Is a well test or inspection required when you buy?

It depends on where you live. Three examples, confirmed on each agency’s site:

• New Jersey requires testing as a condition of sale for homes on private wells, for a long list of parameters including bacteria, nitrate, arsenic, lead, VOCs and some PFAS (N.J.A.C. 7:9E).
• Oregon requires the seller to test for arsenic, nitrate and total coliform bacteria at an accredited lab, and to send the results to the buyer and the state (Oregon Health Authority).
• Minnesota doesn’t require testing or inspection at sale statewide. Sellers must disclose all known wells and their status. Dakota County requires testing at transfer by local ordinance, and some lenders may require coliform and nitrate tests (MDH).

Other states have different rules, or none. Check your state’s program in EPA’s State Program Directory, and ask your lender what it requires.

Step 1: Ask for the well’s paperwork

The Minnesota Department of Health suggests buyers ask for (MDH):

• [ ] Well construction records (the well log)
• [ ] Well sealing records for any old wells
• [ ] Past water test reports
• [ ] Repair and maintenance records

Some states keep well records online. Minnesota has the Minnesota Well Index (MDH), and Oregon points sellers to the Water Resources Department’s Well Report Query tool (OHA). Your state well program can tell you where to look.

Step 2: Have the well inspected

MDH doesn’t inspect wells at property transfer, but it notes that well contractors and some professional inspectors do inspect wells and water systems. MDH lists these as common defects and things to check (MDH):

• [ ] Loose or damaged well cap
• [ ] Cracked casing
• [ ] Soil settling around the casing, or an open gap around it
• [ ] Casing height above ground (Minnesota requires at least 12 inches)
• [ ] Distances from septic systems and other contamination sources
• [ ] Water pressure
• [ ] Any water treatment equipment
• [ ] Taste, odor and staining
• [ ] Age of the well
• [ ] Water quantity: whether the well yields enough for your household, since some wells or aquifers don’t

Unused wells matter too. In Minnesota, a well that’s “not in use” must be put back into use, sealed by a licensed contractor, or kept under an annual maintenance permit (MDH). Ask whether there are any old wells on the property.

Step 3: Test the water

Minimum tests. CDC recommends that every well be tested yearly for total coliform bacteria, nitrates, total dissolved solids and pH (CDC). MDH also recommends testing a well at least once for arsenic, testing tap water at least once for lead, and suggests buyers check iron, manganese, sulfate and hardness for staining and odor issues (MDH).

Local concerns. Ask the county health department what else is common nearby, such as uranium, radon, PFAS or pesticides. See what to test well water for.

Getting a clean sample:

• Use a state-certified lab. Find one in EPA’s directory.
• Find out who will collect the sample. New Jersey’s rule requires a certified lab or its authorized representative to collect it.
• If the home has a treatment system, ask where the sample comes from. New Jersey requires the sample to be taken before the treatment system, or with the system disconnected (N.J.A.C. 7:9E), so the results show the raw well water.
• Check how old any seller-provided results are. New Jersey treats results as valid for one year, and coliform results for six months. Oregon accepts results for one year.

For a broad mail-in panel, see Tap Score: Advanced well water test →. If your state requires a certified or accredited lab for the sale, confirm the lab qualifies.

Step 4: If results come back high

MDH’s guidance for buyers (MDH):

• Coliform bacteria: don’t drink the water unless it has been boiled (full rolling boil for at least 1 minute). Disinfect the well and retest. If bacteria remain, have a licensed well contractor inspect the well for problems.
• E. coli: this means a greater risk of disease. A licensed well contractor should check the well construction and find the source.
• Nitrate, arsenic, lead or other contaminants above recommended levels: options include treatment or another water source, which could mean a new well. MDH notes that nitrate-nitrogen above 10 mg/L can cause blue baby syndrome in infants.

Talk with your agent or attorney about what the contract allows, such as repairs, credits or extra time to retest. Get quotes from licensed contractors before you negotiate.

More: coliform and E. coli · nitrates · arsenic · lead · how to read your results · shock chlorination · treatment options

After you move in

Once you own the home, you’re responsible for testing, maintaining and repairing the well (MDH). Set up a yearly testing routine: how often to test well water.