 This avoided the expensive operation of frequent replacing of and relocating of inadequate bridges, as happened at Moss Vale when the 30-year old wrought iron truss was removed then rebuilt at Liverpool over the Georges River to serve the military area.The cost-effectiveness of the policy has been proved at Moss Vale, and many other sites, because the bridges are still in use carrying the modern heavy diesel locomotives with strings of heavy bulk wagons.The Argyle Street railway bridge is a large steel through Pratt truss bridge on a 40.54 m (133 feet) skew span with brick abutments and wing walls.