(a) The portion of Interstate Highway 35 in the municipal limits of Hillsboro is designated as the Trooper Milton Alexander Memorial Highway. The designation is in addition to any other designation.
(b) Subject to Section 225.021(c), the department shall:
(1) design and construct markers indicating the designation as the Trooper Milton Alexander Memorial Highway and any other appropriate information; and
(2) erect a marker at each end of the highway and at appropriate intermediate sites along the highway.