RSA 482-A:26 Dwellings Over Water.

I. No person shall construct any structure suitable for use as a dwelling if the structure or any part of the structure extends beyond the shoreline of any public water or publicly-owned water body.
II. No person shall convert or modify any existing structure in order to make the structure suitable as a dwelling if the structure or any part of the structure extends beyond the shoreline of any public water or publicly-owned water body.
III. (a) Existing dwellings over water which were constructed or converted to be made suitable for use as a dwelling in accordance with the law in effect at the time of construction or conversion, may be repaired or reconstructed, for maintenance purposes only, using any modern technologies, provided the result is a functionally equivalent