ENID, OK – An ongoing review of city bridges has found only six that are capable of supporting its heaviest firefighting truck, according to the Web site www.kotv.com. The survey was prompted by the collapse last month of a bridge rated for 13 tons when it was crossed by a 35-ton ladder truck, the heaviest truck in the city’s fleet. The city has started a structural evaluation of about 76 bridges in Enid. City engineers are about two-thirds of the way through the inspection process. Since the study began, the posted weight limit has been lowered on two bridges, including one bridge that dropped from a 36-ton weight limit to 12 tons. Most fire vehicles won’t be able to travel over the bridge under the new weight restriction unless they are responding to a structure fire. For other calls, lightweight trucks will be sent over the bridge. Another bridge, on Leona Mitchell Boulevard, dropped from 23 tons to 10 tons. Fire officials have asked the city to post weight limits on all bridges, regardless of their capacity.