The highway administrator shall make a yearly report to the county commission during the month of January, for the preceding year, in which he shall include a detailed statement of the conditions of established public highways, roads, bridges and culverts and the amount of money expended for construction, maintenance and repair of such highways, roads, bridges and culverts during the preceding year. He shall estimate balances, revenue and receipts creditable to any county road and bridge fund, special or otherwise, and shall submit for approval by the commission a plan for construction, reconstruction, maintenance and repair of existing established public highways, roads, bridges and culverts proposed to be undertaken and completed during the current year. The highway administrator shall file such other reports from time to time as he deems necessary or as requested by the county commission.