Nothing in this Part shall preclude a river or segment of a river from becoming part of the national wild and scenic river system. The Secretary is directed to encourage and assist any federal studies for the inclusion of North Carolina rivers in the national system. The Secretary may enter into cooperative agreements for joint federal-state administration of a North Carolina river or segment of river: Provided, that such agreements relating to water and land use are not less restrictive than the requirements of this Part. (1971, c. 1167, s. 2; 1973, c. 1262, s. 86; 2015-241, ss. 14.30(f), (m).)