Taxes for the payment of bonds issued under section 260C.19 shall be levied in accordance with chapter 76. The bonds shall be payable from a fund created from the proceeds of the taxes in not more than twenty years and bear interest at a rate not exceeding the rate permitted by chapter 74A, and shall be of the form as the board issuing the bonds shall by resolution provide. Any indebtedness incurred shall not be considered an indebtedness incurred for general and ordinary purposes.