(a) The board of directors shall have control of the construction of the works provided for in the improvement plan.
(b) It may advertise in local or state papers or papers published in other states for proposals for doing any work by contract. No work exceeding one thousand dollars ($1,000) shall be let without public advertisement. The board may accept or reject any proposals.
(c) If the improvement plan is undertaken in cooperation with the United States, the board may enter into an agreement providing for the construction of the works of improvement and awarding of contracts therefor, to be by, and under the control and supervision of, the United States or any agency or instrumentality thereof. In that event the advertisement, award, and carrying out of the contracts shall be in accordance with the provisions of law applicable to such federal agency.
(d) All contractors shall be required to give bond for the faithful performance of such contracts as may be awarded them for construction of the works provided for in the improvement plan, with good and sufficient sureties, in an amount to be fixed by the board. The board shall not remit or excuse the penalty or forfeiture of the bond or the breaches thereof.
(e) The board may:
(1) Appoint all necessary agents for carrying on the work and fix their pay;
(2) Buy all necessary materials and implements and sell any material or implements as may be on hand and which may not be necessary for the completion of the improvements; and
(3) Make all such contracts in the prosecution of the work as may best subserve the public interest.
(f) It shall be the duty of the board to have the amount of work done by any contractor estimated, from time to time as may be desirable, by the engineer selected by the board. The board shall draw its warrants in favor of the contractor for not more than ninety percent (90%) of the amount of work so reported, reserving the remainder until it has been ascertained that the work has been completed according to contract and is free from liens.