When the County Board determines that a maximum speed limit is greater or less than is reasonable or safe with respect to the conditions found to exist along any county or township highway, or part or zone there of, within the county, except those that are under the jurisdiction of the State Department of Transportation or the Illinois State Toll Highway Authority, the County Board shall determine and declare by, ordinance, a reasonable and proper absolute maximum speed limit as follows:
(A) Does not exceed 55 mph;
(B) Increases the limit within an urban district to not more than 55 mph;
(C) Decreases the limit within an urban district to not less than 20 mph;
(D) Decreases the limit outside of an urban district to not less than 35 mph, except as otherwise provided in division (E) below;
(E) Decreases the limit within a residence district to not less than 25 mph, except as otherwise provided in division (C) above;
(F) Not more than six alterations shall be made per mile, and the difference in limit between adjacent altered speed zones shall not be more than ten mph; and
(G) Minimum speed limits may be posted at any locations where it has been determined that the slow vehicles are impeding the flow of traffic.
(Res. passed 3-13-2007)