65 ILCS 5/11-115-1

Whenever the State of Illinois appropriates money for the purpose of aiding in the construction of or for the purpose of constructing works to protect against floods, the corporate authorities of any municipality benefited, or to be benefited, by that protection have the power to contract with the State of Illinois through the department charged with the construction of those works for the taking over and maintenance thereof. Such a contract may be entered into either before or after the works have been constructed.