(a) Except as provided in subsection (b) and except when a special hazard exists that requires lower speed for compliance with Kan. Stat. Ann. § 8-1557, and amendments thereto, the limits specified in this subsection or established as authorized by law shall be maximum lawful speeds, and no person shall operate a vehicle at a speed in excess of such maximum limits:

(1) In any urban district, 30 miles per hour;

(2) on any separated multilane highway, as designated and posted by the secretary of transportation, 75 miles per hour;

(3) on any county or township highway, 55 miles per hour; and

(4) on all other highways, 65 miles per hour.

(b) No person shall drive a school bus to or from school, or interschool or intraschool functions or activities, at a speed in excess of the maximum speed limits provided in subsection (a), except that the board of education of any school district may establish by board policy lower maximum speed limits for the operation of such district’s school buses. The provisions of this subsection relating to school buses shall apply to buses used for the transportation of students enrolled in community colleges or area vocational schools, when such buses are transporting students to or from school, or functions or activities.

(c) The maximum speed limits in this section may be altered as authorized in Kan. Stat. Ann. §§ 8-1559 and 8-1560, and amendments thereto.