(a) In order to hasten the work, the board may borrow money at a rate of interest not exceeding the maximum rate prescribed by the Constitution of the State of Arkansas at the time of issuance. The board may issue negotiable bonds therefor signed by the members of the board and may pledge all assessments for the repayment thereof.
(b) It may also issue to contractors to do the work as negotiable evidences of debt, bearing interest not exceeding the lawful rate of interest prescribed by the Constitution of the State of Arkansas.
(c) No bonds issued under the terms of this subchapter shall run for more than thirty (30) years. All issues of bonds shall be divided so that a portion thereof may mature each year as the assessments are collected, or they may all be made payable at the same time, with proper provision for a sinking fund.