Who is responsible for the culvert under my driveway?

Under RSA 236:13, VI, all private driveway connections, including structures like culverts, remain the continuing responsibility of the landowner- even if located within the right of way. It is immaterial whether the driveway connection pre-dates the town's permit system. If any driveway connection threatens the integrity of the highway due to plugged culverts, erosion, siltation, etc., the planning board or its designee can require the owner to repair it. If the owner refuses to effectuate such repairs, then the town may perform the work and assess the costs to the owner.