(1) The portion of highway I-75 in Saginaw County beginning at Willard Road and extending north to Riverview Road shall be known as the "Trooper Joel E. Popp Memorial Highway".

    (2) The portion of highway M-53 in Macomb County beginning at the intersection with 18 Mile Road and continuing north to the interchange with Hall Road shall be known as the "Officer Leroy Imus Memorial Highway". Subject to section 2, a sign designating the location of the "Officer Leroy Imus Memorial Highway" must be placed at the northbound intersection of highway M-53 and 18 Mile Road and on the southern side of the southbound intersection of highway M-53 and 20 Mile Road.