Unless otherwise provided, whenever by statute a new highway or extension is added to the state highway system, no existing city street or county road may be maintained or improved by the department as a temporary route of such new highway or extension pending the construction of the new highway or extension on the location adopted by the department.
[ 1984 c 7 § 90; 1973 1st ex.s. c 151 § 12; 1965 ex.s. c 170 § 34.]