At 0817 Car 3 Engine 1 Rescue 5 Engine 2 and utility 64 along with NCVAC were alerted for a Motor vehicle accident involving a box truck. It had struck the Metro-North railroad bridge on route 106 rolled over and began leaking diesel fuel from its saddle tanks. Engine 4 in place of Engine 1 took the call after clearing the scene of a prior accident in the North end of town. Car 3 and Rescue 5 arrived on scene to confirm the initial dispatch. The occupants had self-extricated with minor injuries. Engine 4 arrived on scene and helped Rescue 5 control fluids and all hazards. New Canaan PD closed down route 106 at Weed Street and at Lapham road. In addition Metro-North shut down train service on the New Canaan line for about an hour and a half until the bridge was inspected and found to have no structural damage. All fire units remained on scene until 1000 at which point the truck was removed. Car 3 had route 106 command.