Talk:National Bridge Inventory

From Wikipedia, the free encyclopedia

does anyone know how many total bridges there are in the united states?

[edit] Number of Bridges

According to the FHWA a normal bridge spans 20' or more. Any bridge shorter than that is considered a short-span bridge, and is normally not included in the NBI. These short-span bridges are normally maintained by the local public works/services of the area they are located in. Each state's DOT manages their bridge inventory a little different, but must conform to the minimum standards set forth by the FHWA. Federal law requires any bridge of 20' or longer to be inspected at 2 year intervals or less. So to answer the question of how many bridges there are in the United States, you would have to go to each county and large city of everystate to count them. That would not include the number of private bridges that are owned by landowners, which are not accounted for by the government. Another structure that can be considered a short span bridge, is a culvert pipe with a diameter of 4'-5' and up. Hope this information is helpful.