The department shall:
(1) Collect data and information as to all roads in the state and, when practicable, have maps and plats thereof made.
(2) Investigate and collect data and information as to the best methods and materials for road building and repair.
(3) Investigate and gather information as to road building and repair in the different localities in the state.
(4) Compile all such data and information and furnish it to counties upon request.
(5) Keep on file at the department headquarters copies of such data and information as a public record.