(1) Nothing in Sections 15-24-1160 or 15-24-1180 shall be interpreted to prohibit the following:
(a) The operation of any tank vehicle upon any officially designated detour from any established flammable liquids route which has been closed to motor vehicle traffic;
(b) The delivery of such liquids by tank vehicle from primary supply sources to any wholesale bulk plant or user bulk storage which does not abut on an established route; provided, that in making any such excepted delivery the tank vehicle shall proceed on an established route and shall depart therefrom from an intersecting street which is nearest the destination to which such delivery is to be made and upon completion of such delivery shall return to the nearest established route; provided, however, that nothing contained in Sections 15-24-1160 to 15-24-1210, inclusive, shall authorize the operation of any tank vehicle upon any street, avenue or public place from which such vehicle is barred by any other ordinance of the City of Chicago or any governmental authority.
(2) In the event and during the time that any established route or part thereof or any highway outside the city connecting with an established route shall be rendered impassable or unsafe for the transportation of Class I flammable liquids by act of God or by reason of any accident, emergency or occurrence, any tank vehicle which would normally operate over such route may be operated over any other established route which will enable such vehicle most expeditiously to reach its destination, or such tank vehicle may be detoured around the impassable or unsafe portion of said route or highway by the shortest way available on streets, avenues or public ways upon which motor truck traffic is permissible.
(Prior code § 129.1-108)