Any bonds issued under this article may contain a provision requiring the establishment of a reserve or reserves in an amount equal to the requirements of principal and interest payments for the two years during the life of the bonds requiring the largest amount of principal and interest payments, and the district shall maintain the reserve during the life of the bond issue for the purpose of protecting against any deficiency in rental payments or tax collections. If it becomes necessary to withdraw funds from the reserve to protect against any deficiency, the board of directors of the district shall levy a tax on all the taxable property in the district or utilize service or rental charges accruing to the district sufficient to maintain the reserve fund in an amount equal to the original amount thereof. In making the levy for the payment of principal and interest for the last year when the bonds mature, the board of directors shall take into consideration the amount of money then in the reserve fund and shall levy an amount sufficient to pay the principal and interest on the bonds, less the amount then in the reserve fund.