(a) As used in this chapter, unless the context otherwise requires, "maintenance" means the constant making of all repairs necessary to preserve a smooth surface on the roads and to keep the bridges and culverts in a safe condition and shall include drainage work, the building of bridges and culverts, and the making of cuts and fills as the commission deems necessary to accomplish these purposes.

(b) It shall be the duty of the State Highway Commission to begin as soon as practicable and continue the maintenance of all roads that are properly designated as state highways, to the end that every part of the state highways shall be properly, fairly, and equitably maintained and kept in repair.

(c) So far as practicable, maintenance and repair shall be according to what is known as the patrol system. Laborers as are deemed necessary may be employed and kept continually on the roads, with the force, equipment, and materials that are necessary to perform the work.

(d) The commission may make all necessary contracts, purchase all necessary equipment, supplies, and materials, and employ all necessary labor and is given all other necessary powers to provide for maintenance and shall pay for the same out of the State Highway and Transportation Department Fund.

(1) However, all contracts so let in excess of one thousand dollars ($1,000) made by the commission shall be let on a competitive basis to the lowest responsible bidder.

(2) The commission may reject all bids.

(3) All bids shall be sealed bids and shall be filed with the commission in open session and opened and tabulated during that session of the commission.

(4) No such contract shall be valid unless signed by at least three (3) members of the commission and attested to by the secretary.