Any two or more counties may acquire, construct, maintain and operate a viaduct or bridge wholly within the territorial limits of one county in the same manner as is herein provided for the acquisition, construction, maintenance and operation of viaducts and bridges over any ravine, marsh, river or stream forming in whole or in part the boundary between counties.
All provisions in this article contained referring to a joint viaduct or bridge between counties shall be applicable to any such viaduct or bridge wholly within the territorial limits of one county.