The Division of Ports and Harbors (DPH), of the Pease Development Authority, shall "plan for the maintenance and development of the ports, harbors, and navigable tidal rivers of the State of New Hampshire from the head of navigation to the seaward limits within the jurisdiction of the state, in order to foster and stimulate commerce and the shipment of freight through the state’s ports and as an agency of the state, to assist shipping and commercial and industrial interests that may depend on the sea for transport of products." The DPH assists in the establishment of accommodations for the boat traveler, the area boat owner, the pleasure fishermen and others who pass up and down the New Hampshire coastline or in its tributaries.