The county engineer shall be the custodian of all road tools, machinery, supplies, and equipment of St. Clair County, and shall be accountable for the same, at all times. The county commission shall furnish the necessary storage facilities in which to keep tools, machinery, supplies, and equipment, and the county engineer shall keep on files in his or her office at all times, an up to date inventory, containing a list of all tools, machinery, equipment, and supplies belonging to St. Clair County. (Acts 1971, No. 1728, p. 2889, § 10.)