transfer by commissioner; dual purpose use.

Notwithstanding any other provisions of this act or any other law, the commissioner is authorized to use either exclusively for, or in conjunction with, flood control purposes any property under his jurisdiction acquired for other public purposes. Transfer of such use shall be effected by an official order of the commissioner to be filed in the offices of the department and of the department of state, accompanied by a description and map of such property. When the use is to be exclusively for flood control purposes then upon such filing of the description, map and official order of tranfer of use, the property shall be used and maintained for flood control purposes and be governed as though the said property was acquired pursuant to the provisions of this article for flood control purposes. When dual use is to be made of such property for flood control purposes and other public purposes by the state, the official order of transfer shall so certify, and upon such filing of the description, map and official order of transfer, the property shall be used and maintained for such dual purposes, and is, in the discretion of the commissioner, to be governed either by this article or the act under which jurisdiction was acquired by the commissioner or both. When grade crossing elimination property is involved, the official order of transfer shall also be approved by the commissioner of transportation.