It shall be the duty of the county engineer, in accordance with policy established by the Coffee County Commission, within the law of the State of Alabama, (1) to employ, supervise, and direct all such assistants as are necessary to properly maintain and construct the public roads, highways, bridges, and ferries of Coffee County, and he or she shall have authority to prescribe their duties, and to discharge employees for cause; (2) to perform such engineering service and surveying as may be required; (3) to maintain the necessary accounting records to reflect the cost of the county highway system; (4) in accordance with the policies and priorities established by the Coffee County Commission, to build or construct new roads, or change old roads; (5) to locate within the various districts of Coffee County the necessary equipment to perform routine maintenance of all public roads, highways, bridges, and ferries on a continuing basis; (6) it shall be his or her further duty, insofar as is feasible, to construct and maintain all county roads on the basis of the county as a unit, without regard to any district or beat lines.