620 ILCS 40/6
The county board of every county has the power (1) to lease all or any part of such an airport, landing field, facilities, and other structures, and fix and collect rentals therefor, (2) to fix, charge, and collect rentals, tolls, fees, and charges to be paid for the use of the whole or any part of such an airport or landing field, buildings, or other facilities, (3) to make contracts for the operation and management of such an airport, landing field, or other air navigation facilities, and (4) to provide for the use, management, and operation of such an airport, landing field, or air navigation facilities through lessees thereof, or through its own employees, or otherwise. However, no lease for the operation or management of such an airport, landing field, or air navigation facilities shall be made for more than one year except to the highest and best bidder, after notice of the lease or contract has been given by at least one publication, made at least one week before the date of the lease or contract, in a newspaper of general circulation published in the county.
620 ILCS 40/6