In 1997, the use of tridem drive log hauling vehicles was approved for use on BC highway. With the move to highway-type tridem drive tractors pulling tridem pole trailers, the adequacy of single span bridges on off-highway haul roads needed to be evaluated. In 1999, FERIC studied the adequacy of single span bridges, designed to BC Ministry of Forests standards, with respect to the new 7-axle vehicles carrying off-highway-size loads, and presents the findings in this report.