Whenever the corporate authorities of any city of this Commonwealth shall find, and by ordinance declare, that any public landing, or public wharf, or part thereof, fronting on any navigable river and lying within its limits, has become unnecessary for use for public landing or public wharf purposes, such city shall have the right to take, enter upon, and occupy for use for any other public purposes whatsoever, the public landing, or public wharf, or part thereof, so found unnecessary for such purposes, any limitation of use thereof by the municipality arising from donation, dedication, appropriation, statute, or otherwise, to the contrary notwithstanding.