Do you need to test well water before selling your house in Lane County, Oregon?
Yes. If your Lane County home gets its water from a well, Oregon law requires you to test it for arsenic, nitrate, and total coliform bacteria once you accept an offer to buy or trade the property. As the seller, you're responsible for ordering the test and reporting the results to both your buyer and the Oregon Health Authority, and the requirement can't be waived — even if your buyer says they don't care about the results.
By Chase Maillard, REALTOR® | November 2, 2026
If you own an acreage property in Creswell, Cottage Grove, or Pleasant Hill, there's a good chance your water doesn't come from a city line. It comes from a well on your own land — and that well comes with a legal obligation the moment you accept an offer on your home.
I get this question from almost every seller with a private well, usually right after we've gone under contract: "Wait, I have to test my water now?" Yes, you do. It's not optional, and it's not something your buyer can waive just because they're not worried about it.
Here's exactly what Oregon law requires, what it means for your timeline, and what happens if the results come back with something you don't want to see.
Oregon put this rule in place because private wells don't get the same ongoing oversight that municipal water systems do. Nobody is testing your water on a schedule the way a city utility tests its supply. The only point in the life of most rural properties where the water actually gets checked is when the home changes hands — which is exactly why the law ties the requirement to accepting an offer, rather than to listing or closing.
What Oregon's well water law actually requires
Under ORS 448.271, any sale or exchange of real estate that includes a well supplying domestic water triggers a testing requirement — and it kicks in the moment you accept an offer, not at closing and not when you first list.
As the seller, you're required to:
Have the well tested for arsenic, nitrate, and total coliform bacteria
Report the results to both your buyer and the Oregon Health Authority (OHA) within 90 days of getting your lab results back
Submit a Water Systems Data Sheet along with the lab slips
A few details that trip people up:
This applies even if the well sits on a neighboring property, as long as your buyer's purchase includes rights to use it — say, through an easement.
A capped well on a vacant, unimproved lot is exempt, since nothing is currently drawing water from it.
Test results are good for one year when they're tied to a property sale, so if you tested recently for another reason, it may already satisfy this requirement.
The Oregon Health Authority can require testing for additional contaminants in some areas with known water quality concerns, so it's worth checking with your lab or agent about anything specific to your part of Lane, Linn, or Douglas County.
One thing I want to be clear about: this test cannot be waived. I've had buyers tell their agent they don't need to see it — it doesn't matter. The law requires it regardless of what the buyer is willing to skip.
If you haven't already walked through how to prepare a Lane County acreage or high-end home for sale, add this to that list before you go under contract. Lining up a state-certified water testing lab early means you're not scrambling once an offer lands.
A practical note on timing: because the clock starts when you accept an offer, not when the test comes back, it's worth asking your lab up front how long results typically take, rather than finding out mid-escrow. Bacteria, nitrate, and arsenic testing don't always run on the same timeline, so get a straight answer from the lab you choose before you count on a specific closing date. Building that lead time into your schedule now saves you from a last-minute scramble to meet the 90-day reporting window later.
What happens if arsenic or nitrate comes back high
This is the part that actually worries people, and I understand why — nobody wants to hear their water might not be safe.
Here's the honest answer: Oregon's law is a reporting requirement, not a pass/fail test. The statute is explicit that failing to comply — or getting results you don't love — does not invalidate your sale. The state isn't requiring the test to come back clean. It's requiring that the results get reported, so your buyer has full information about what they're getting into.
That said, a high arsenic or nitrate reading can absolutely affect your transaction in practical ways:
Your buyer may ask for a water treatment system as a condition of moving forward, similar to how a repair request works after a home inspection.
It can become a point of renegotiation the same way an inspection finding would — this is where it helps to already understand what happens if you need to back out of a real estate contract in Oregon, since contaminated water isn't a reason a sale falls apart on its own, but it can absolutely become leverage in the conversation.
Some lenders may want the issue addressed — with treatment, a new filtration system, or a re-test — before they'll fund certain loan types.
If you're worried about what your well might show, order the test as early as you can once you're under contract. A result you know about gives you time to respond. A result you don't know about until late in escrow gives you a lot less room to work with.
If you're buying a well-served property in Lane County
If you're on the buying side of a Creswell, Cottage Grove, or Pleasant Hill acreage listing, this same law protects you. Your seller is legally obligated to get you these results, and you're entitled to see them before you waive your contingencies.
Ask your agent whether the seller has already ordered the test as soon as you're under contract. Don't assume no news is good news. If results haven't come back yet and you're approaching a contingency deadline, that's worth a direct conversation with your lender and agent about timing.
Water isn't the only thing rural buyers have to sort out that city buyers typically don't — insuring a rural or acreage property comes with its own set of considerations too. If you haven't looked into it yet, can you still insure a rural or acreage home in Lane County is worth a read before you're deep into your due diligence period.
Water testing is one of several Lane County–specific steps that can catch sellers and buyers off guard if nobody mentions them ahead of time. It's not something to be anxious about — it's just one more box to check, and knowing it's coming means you can get ahead of it instead of being surprised by it mid-escrow.
If you're getting ready to list a well-served acreage property in Creswell, Cottage Grove, or anywhere else in Lane County and want to know where your home stands before you go under contract, I'd be glad to walk you through it. Curious what your home could be worth in today's market? Get a free, no-obligation home value report from me — just visit What's Your Home Worth to get started.
Frequently Asked Questions
Who pays for the well water test when selling a house in Oregon?
Oregon law places the testing and reporting obligation on the seller, but the statute doesn't specify who has to cover the cost. In most Lane County transactions, this gets worked out between buyer and seller like any other closing cost or credit, so it's worth raising with your agent early rather than assuming either way.
What exactly does an Oregon well water test check for?
State law requires testing for arsenic, nitrate, and total coliform bacteria. The Oregon Health Authority can require additional contaminant testing in specific areas with known water quality concerns, so check with your lab or agent about anything particular to your part of Lane, Linn, or Douglas County.
Does a bad well water test mean I can't sell my house?
No. Oregon's law is a disclosure and reporting requirement, not a pass/fail standard — a high reading doesn't invalidate your sale. It can, however, become a point of negotiation with your buyer, similar to a finding from a home inspection.
How long is a well water test good for?
When a test is tied to a property sale, Oregon treats the results as valid for one year. If your well was tested recently for another reason, it may already satisfy this requirement, so check the date on your paperwork before ordering a new one.
Do I still need to test the well if my buyer says they don't want it done?
Yes. The requirement can't be waived, even if your buyer agrees to skip it. As the seller, you're still obligated to have the well tested and report the results to both your buyer and the Oregon Health Authority.
About Chase Maillard, REALTOR®
Chase Maillard is a REALTOR® with Keller Williams Realty and leads CM Realty, a two-person team serving Lane, Linn, and Douglas counties in Oregon. She works with both buyers and sellers across Creswell, Cottage Grove, Eugene, Springfield, and Pleasant Hill, with a focus on luxury and acreage buyers and sellers.