... material for the main span. Values shown in the “Total” columns includebridges constructed using other materials such as masonry, aluminum, cast iron and wrought iron.Therefore, the sum of the values ... bridges in the state andsubmits them annually to the FHWA, where they are entered into the National Bridge Inventory(NBI) database. The NBI must be updated annually as existing bridges are reinspected, ... ensure the safety of the traveling public. The states are responsible for assuring that owners of all bridges on public roads perform the required inspections. Each state then collects the inspection...