Taxes for the payment of bonds issued under section 145A.17 shall be levied in accordance with chapter 76 and in the same proportion as provided in section 145A.14 . Any indebtedness incurred shall not be considered an indebtedness incurred for general and ordinary purposes. [C71, 73, 75, 77, 79, 81, §145A.18 ] 85 Acts, ch 123, §9