The interest of an owner in water rights, power rights, and flowage rights, or any of such rights, owned by severance from real estate interests set in the grand list to another and in connection with which such rights exist, shall be appraised and set in the grand list as real estate to the owner of such rights. This section shall not be construed so as to affect any exemptions from taxation granted under any existing statute.
32 V.S.A. § 3605