What Is the NBI?
The National Bridge Inventory (NBI) is a US Federal Highway Administration database containing inspection records for over 600,000 bridges across the United States. RoadScope indexes this data and overlays it on your route maps.
What NBI Data Includes
- Bridge location (coordinates)
- Structure type and material
- Vertical clearance (roadway and railroad)
- Weight ratings (Operating and Inventory ratings)
- Deck width and number of lanes
- Last inspection date and condition rating
How RoadScope Uses NBI Data
When you draw a route, RoadScope automatically identifies all NBI bridges within the route corridor and adds them as POIs with their documented clearance and weight data.
**Important:** NBI data reflects documented values as of the last inspection. Always verify critical constraints with field survey — bridges may have been modified, restricted, or changed since the NBI record was updated.
NBI + Field Survey
The most defensible route documentation combines NBI data (for initial screening and historical context) with current field measurements. When your field-measured clearance differs from the NBI value, document both and note the discrepancy.
Canadian Bridge Data
For Canadian routes, RoadScope uses SolTecCAN data from the National Road Network (NRN) as the equivalent bridge intelligence layer.