70 ILCS 2605/5.11

The appropriation ordinance including the amounts for the payment of contract liabilities, or to defray the expense of any project or purpose shall not be construed as an approval of the board of any of said contract liabilities or of any project or purpose mentioned but shall be regarded only as the provision of a fund, or funds, for the payment thereof when said contract liabilities have been found to be valid and legal obligations against the said district, and when properly vouchered and audited by the Department of Finance, or when any project or purpose is approved and authorized by the board of commissioners of the district as the case may be.