N.H. Rev. Stat. Ann. § 47:11

The city councils shall have power to construct drains and common sewers through highways, streets or private lands, paying the owners such damages as they shall sustain thereby, the damages to be assessed by the mayor and aldermen in the same manner and with the same right of appeal from their decision as in case of the laying out of highways; and may require all persons to pay a reasonable sum for the right to open any drain into any public drain or common sewer.