The director shall take such action as necessary to control rat populations on publicly owned property throughout the county; provided, that, for any property controlled by any agency, other than the county government, such agency shall be required to reimburse the county for the cost of rat control. (1971 L.M.C., ch. 48, § 1; 1972 L.M.C., ch. 16, § 13; 1981 L.M.C., ch. 4, § 1.)