This point shapefile depicts the more than 600,000 of the United States' bridges located on public roads, including interstate highways, United States highways, state and county roads, as well as publicly-accessible bridges on federal lands. It presents a state by state summary analysis of the number, location and general condition of highway bridges within each state. This layer is part of the 2014 National Transportation Atlas Database. The National Transportation Atlas Databases 2014 (NTAD2014) is a set of nationwide geographic datasets of transportation facilities, transportation networks, associated infrastructure and other political and administrative entities. These datasets include spatial information for transportation modal networks and intermodal terminals, as well as the re¬lated attribute information for these features. This data supports research, analysis, and decision-making across all transportation modes. It is most useful at the national level, but has major applications at regional, state and local scales throughout the transportation community. The data used to compile NTAD2014 was provided by our partners within the United States Department of Transportation (USDOT) and by other agencies throughout the United States Federal Government. These contributors are the actual data stewards and are ultimately responsible for the maintenance and accuracy of their data. The National Bridge Inventory (NBI) published by the United States Department of Transportation Federal Highway Administration documents the United States' bridge inventory. Data collected includes design of the bridge and the dimensions of the usable portion. The data is often used to analyze bridges and judge their conditions. The bridge inventory is developed with the purpose of having a unified database for bridges, including identification information, bridge types and specifications, operational conditions, bridge data including geometric data and functional description and inspection data. Any bridge more than 20 feet (6 meters) long used for vehicular traffic is included.
