Septic & Well Inspections in NH: A Homebuyer's Checklist

A home inspection, septic evaluation, well-yield test and laboratory water analysis answer different questions. When buying a New Hampshire home with private systems, confirm which services are included, who will perform them and when you will receive the results.

Start with the property's records and your contract deadlines. On the Seacoast, a home can have municipal water and private septic, a private well and municipal sewer, or both private systems. Verify each connection rather than inferring it from the neighborhood.

Request the records before scheduling

• The septic design, approval for construction and approval for operation, if available.
• Installation, pumping, repair and service records, including any treatment equipment.
• The well completion report and available pump or pressure-tank records.
• Previous laboratory reports, treatment-system specifications and maintenance records.
• Recorded easements or shared-system agreements affecting access, maintenance and cost allocation.

Ask the evaluator to compare the documented system with the house's current use and any planned bedrooms or additions. A listing's bedroom count is not proof of approved septic capacity. Missing records are a question to investigate, not an automatic conclusion that the system is acceptable or failing.

Understand the scope of the septic evaluation

Ask a qualified evaluator what components will be located and assessed, what access is needed, whether pumping is part of the process, and what site or seasonal conditions limit the conclusions. Coordinate any pumping with the evaluator rather than scheduling it independently immediately before the inspection.

The report should explain the observed condition, inaccessible components, evidence of problems and recommended follow-up. An evaluation is not a guarantee of remaining service life. Have the evaluator explain whether an issue calls for maintenance, repair, further investigation or a replacement design.

The EPA's homebuyer septic guide provides a useful starting point for understanding the system and arranging an inspection before purchase.

Waterfront transfers have additional requirements

RSA 485-A:39 applies to developed waterfront property using septic when any portion of the system lies within 250 feet of the statutory reference line. It generally requires the buyer to engage and pay for a New Hampshire licensed septic system evaluator before transfer.

A buyer may accept a qualifying seller evaluation completed within 180 days of transfer and acknowledge that acceptance in writing. An additional determination by a New Hampshire permitted septic designer is required when the system has no NHDES approval or the approval predates September 1, 1989. That determination concerns the disposal area's elevation relative to seasonal high groundwater and whether the system is in failure.

The statute includes disclosure, notification and replacement obligations when failure findings trigger them, including replacement within 180 days after transfer. It also provides a separate repair-or-replacement route with pre-transfer notification and post-transfer reporting, and an extension process for circumstances beyond the buyer's control. Ask the evaluator and transaction attorney to establish the applicable requirements early.

For the reference line and other coastal permitting questions, see our NH waterfront regulations guide. Do not assume that a standard inspection contingency or its waiver addresses every statutory obligation.

Well quantity and water quality are separate

A well-yield assessment addresses the water supply's performance. A laboratory analysis addresses the substances and organisms included in that particular test. Clear water and good pressure during a showing do not establish drinking-water quality.

Ask the well professional how the proposed test evaluates output, drawdown and recovery, what it can establish about household demand, and what seasonal limitations remain. Compare the findings with your intended use and the lender's requirements. A brief faucet test is not the same as a documented well assessment.

If the well is shared, review the recorded agreement and ask who operates the equipment, authorizes repairs, pays electricity costs and resolves an interruption.

Order a test panel suited to a New Hampshire private well

Use an accredited laboratory and follow its sampling instructions. NHDES publishes laboratory and testing information for private wells, including recommendations for buyers. Ask the lab to identify its current New Hampshire homebuyer panel and any additional tests appropriate to the property.

Discuss bacteria, nitrate, arsenic, lead, radon, uranium, PFAS and other locally relevant concerns with the laboratory or NHDES. Confirm exactly what the package includes; a result for one contaminant does not rule out the others. Ask whether samples should be taken before treatment, after treatment or both, and document where each sample came from.

The EPA's private-well guidance explains why testing and local advice matter. Water testing and indoor-air radon testing are different services. Do not apply an indoor-air radon action level to a water-test result; have the appropriate professional interpret the correct sample type, units and guidance.

Notifications are not water-test results

New Hampshire's RSA 477:4-a requires specified buyer notifications about radon, arsenic, lead, PFAS and flood risk before execution of a purchase-and-sale contract involving a building, with buyer acknowledgment.

Those general notifications do not establish the condition of an individual well or replace a laboratory report. Review any property-specific information separately and leave enough time for results and follow-up before your contractual decision deadline.

If the findings need follow-up

Ask for a written description of the problem and a property-specific proposal. For septic work, involve a permitted designer and clarify state and local approval requirements; RSA 485-A:29 governs submission and approval of relevant plans. State review is not limited to waterfront sites.

For water treatment, match the proposal to the actual laboratory results. Request installation scope, ongoing maintenance, replacement media or filters, operating costs and a plan for post-installation testing. Do not assume one generic filter resolves every finding.

Discuss any repair agreement, price adjustment or escrow proposal with your agent, attorney and lender. Acceptance, funding and timing depend on the transaction. A price reduction alone does not resolve a legal replacement deadline or make an unapproved system usable.

Keep a maintenance plan after closing

EPA recommends inspection of an average household septic system at least every three years, with tanks typically pumped every three to five years; alternative systems often need more frequent attention. Actual service depends on the system, household use and professional findings. Follow the EPA's maintenance guidance and your service provider's recommendations.

Set a water-retesting schedule with the laboratory or NHDES, including what to do after repairs, flooding or a suspected change in quality. Keep approvals, inspection reports, laboratory results and service receipts together for future decisions and resale.

Contact Michael Bean to coordinate the real estate timeline and questions for the relevant professionals. For the wider location search, visit our NH Seacoast resource hub.