70 ILCS 200/205-90

Ordinary and necessary expenses; tax anticipation warrants. When there is not sufficient money in the treasury to meet the ordinary and necessary expenses and liabilities of the Authority, the City Council, upon request of the Board, shall order issued warrants against and in anticipation of any taxes levied for the payment of the expenditures for such expenses and liabilities, to the extent of 75% of the total amount of the taxes levied for those purposes.