Keeping a watch over our Lakes with the New Septic System Rules for Waterfront Home Purchases in NH
As of September 1, 2024, important changes took effect for the sale of developed properties with an individual sewage disposal system (ISDS). This is especially important for waterfront properties. These updates shift some of the responsibility for septic system evaluation from the seller to the buyer and add new steps that may affect the closing process and post-purchase obligations.
What Changed?
Under the updated rules, sellers are no longer responsible for hiring a permitted ISDS designer to complete a waterfront site assessment. Instead, the buyer is now responsible for arranging a septic system inspection and evaluation through a permitted septic system evaluator.
In some situations, a permitted ISDS designer may still be needed to determine whether the property’s effluent disposal area (EDA) is in failure due to its proximity to the seasonal high-water table. This step is especially important for waterfront or low-lying properties where drainage and groundwater conditions can impact the system’s performance.
What Happens If the System Is Failing?
If the evaluation shows that the septic system is failing, or if the designer determines that the EDA is in failure, the buyer is required to replace the ISDS within 180 days after the property transfer.
That means buyers should not only plan for the cost of the purchase itself, but also consider the possibility of significant septic system repair or replacement costs after closing. For buyers, this makes due diligence more important than ever.
485-A:39 Waterfront Property Transfer; Septic System Evaluation Required. –
I. Prior to the transfer of any developed waterfront property using a septic system, where any portion of the septic system is within 250 feet of the reference line as defined in RSA 483-B:4, XVII, the buyer of the property shall, at the buyer's expense, engage a New Hampshire licensed septic system evaluator to conduct a septic system evaluation. However, the buyer may accept an evaluation prepared for the seller of the property if the evaluation was completed within 180 days of the date of property transfer. The septic system evaluation prepared for the seller by a New Hampshire state licensed septic system evaluator with stated findings shall be given to the buyer and acceptance of the evaluation shall be acknowledged in writing by the buyer.
Why This Matters for Buyers
A failing septic system can be expensive to fix and may create delays, compliance issues, or unexpected expenses after a property is purchased. If you are buying a developed property—especially one near water—it is essential to understand these requirements early in the process.
Before closing, buyers should:
- confirm whether the property includes an individual sewage disposal system
- schedule a septic system evaluation with a permitted professional
- determine whether a separate review by an ISDS designer is needed
- factor in the possibility of system replacement within 180 days if failure is identified
Final Thoughts
These new rules are designed to ensure septic systems are properly evaluated during property transfers and that buyers understand their responsibilities before purchasing. If you are considering a developed property with an ISDS, especially in a waterfront area, working with qualified professionals early can help you avoid costly surprises.
Click Here for very detailed information from the State of New Hampshire on this subject.
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