Well Water Testing Before Buying or Selling a Home in New Hampshire

Most New Hampshire homes outside the larger downtowns are on private wells, and the state's granite bedrock naturally releases arsenic, uranium, and radon. Because those contaminants are invisible and unregulated on private wells, a buyer's due diligence and a seller's disclosure are how they come to light.

New Hampshire law does require disclosure, even though it does not mandate a specific test. Under RSA 477:4-d, a seller of a one-to-four-family home must give the buyer written information about the private water supply, including its type and location and the date of the most recent water test, along with any known problems such as an unsatisfactory result.

Separately, RSA 477:4-a requires a notification reminding buyers that radon and arsenic can be present in New Hampshire and that testing is recommended. The takeaway is simple: water quality is part of the transaction, and current test results make the disclosure straightforward.

A home-sale test should go beyond bacteria. NHDES recommends a standard analysis that includes arsenic, along with bacteria, nitrate, and the common minerals, plus a radiological test for radon and uranium. In the arsenic belt of southeastern New Hampshire, arsenic deserves particular attention.

Testing usually happens during the inspection period, alongside the home inspection. In practice the buyer most often pays for and orders the test as part of due diligence, though this is negotiable, and a seller who tests ahead of listing can resolve questions before offers come in.

If a test comes back above the New Hampshire arsenic standard or shows another issue, it becomes a normal point of negotiation, much like any inspection finding.

The reassuring part is that the bedrock contaminants are treatable, so a result above a standard rarely needs to break a deal. A buyer or seller can have a licensed local contractor test the water, explain the result, and provide a written quote for a system, which gives both sides a real number to work with.

Installing or crediting for a treatment system is a common way to handle a water finding, and it leaves the next owner with clean water and documentation.

A water test slots neatly into the inspection period of a typical New Hampshire purchase. A sample is collected, sent to an accredited laboratory, and results come back within the inspection window in most cases. Planning the test early in that window leaves room to act on the results before deadlines arrive.

Sellers can get ahead of this by testing before listing. A recent, complete water test answers the disclosure questions under RSA 477:4-d up front and removes a common source of late-stage friction, since the buyer is not left waiting on results during the most time-sensitive part of the deal.

A result above a standard is a normal negotiation point, not a deal-breaker. Because the bedrock contaminants are treatable, the usual outcomes are a price adjustment, a seller credit toward treatment, or a system installed before closing.

Either party can have a licensed local contractor test the water, explain the result, and provide a written, itemized quote, which turns an uncertain finding into a concrete number both sides can work with. The next owner then inherits clean water and the documentation to prove it, which is useful at the following sale as well.