615 ILCS 5/19
It shall be the duty of the Department of Natural Resources to from time to time prepare and devise schemes, plans, ways and means for the reservation or acquisition by the State of desirable tracts of land in connection with the public waters of the State of Illinois, to the end that public reservations or preserves may be made along said public bodies of water for the use of all of the people of the State of Illinois, for pleasure, recreation and sport, and as such reservations or preserves may be made or acquired from time to time, the same shall be under the jurisdiction of the Department of Natural Resources. The Department of Natural Resources is authorized, with the consent in writing of the Governor, to acquire by private purchase or by condemnation in the manner provided for the exercise of the right of eminent domain under the Eminent Domain Act any and all lands sought to carry out the provisions of this Section.
615 ILCS 5/19