The Department of Natural Resources shall have the responsibility of creating a Georgia Scenic Trails System. In carrying out such responsibilities, it shall be the duty of the department to identify and plan the system, to acquire or otherwise gain control over or rights to the use of the necessary land for the system, and to construct, manage, and maintain the system. For the purpose of carrying out its primary duties as provided in this article, the department shall be authorized to exercise any powers heretofore provided by law for the department, except for the powers of eminent domain. Notwithstanding the provisions of any other statute concerning the improvement of land held in fee simple by the State of Georgia, the department shall be authorized to expend state funds for construction, maintenance, and management of trails on lands acquired through purchase, easement, lease, or donation; provided, however, that no buildings shall be constructed on any real estate to which the State of Georgia does not hold title in fee simple, unless it is held under a quitclaim deed with a reversionary interest in the federal government or under a long-term federal license agreement with a reversionary interest in the federal government.