N.H. Rev. Stat. § 482:4
The department is authorized to make such investigations as, in its opinion, the public good requires with respect to high or low water levels in the inland public waters of the state and the rights, instrumentalities and practices which affect or control such levels with a view to the exercise of such control, in a manner consistent with public and private rights and interests, as will best promote the public health and safety and the enjoyment and value of such public waters. When the department may deem expedient, it may ascertain the extent to which owners and managers of dams take into consideration variations of runoff and plan for and anticipate emergencies. Owners of dams, at the reasonable request of the department shall make available to the department such records of water levels and flow of inland public waters as are made and kept by such owners to assist the department in knowing the remaining storage capacity of reservoirs, whether created by dams or otherwise, and to gauge the flow of streams. From time to time, the department may call to conference owners of dams for the purpose of obtaining cooperation in the regulation of stream flow to minimize damage to public and private property at times of high water. Whenever in the opinion of the department an emergency exists or is threatened whereby the public health or safety may be jeopardized by the release or withholding of stored waters, it shall direct such action by the owner or manager of a dam with respect to the release or withholding of water as it may deem necessary in the public interest.
RSA 482:4
1989, 339:1. 1996, 228:106, eff. July 1, 1996.