605 ILCS 5/10-305
The county treasurer of each such county shall be the legal custodian of all funds derived from the issuance of bonds provided for under this Division of this Article and of all revenues derived from the operation of any such bridge, and before he shall receive any such funds he shall be required to post with the county board of such county and subject to their approval, a separate corporate surety bond in an amount to be determined by resolution of such county board. He shall be required to keep proceeds of bonds issued and revenues derived from the operation of any such bridge separate and apart from all other funds which come into his hands as the county treasurer, and the proceeds of bonds issued and the revenues derived from the operation of the bridge shall be by him deposited in separate bank or savings and loan association accounts to be designated for that purpose by the county board of the county. No money shall be paid out of such accounts by the county treasurer except upon an order signed by the chairman of the county board or the chairman of the finance committee of such county board and the county clerk. All such orders shall specify the purpose for which the amount thereof is to be paid with sufficient clearness to indicate the purpose for which the order is issued, and there shall be endorsed thereon the name of the particular fund out of which it is payable, and it shall be paid from the fund constituted for such purpose and from no other fund.
605 ILCS 5/10-305