About the data
The National Bridge Inventory
Every public highway bridge in the United States longer than 20 feet must be inspected at least every two years. The results are reported to the Federal Highway Administration (FHWA), which publishes them once a year as the National Bridge Inventory (NBI). This site is built from the 2025 release, which contains624,192 structures, and was last generated on October 14, 2026.
"Bridge" in the inventory includes culverts, which are pipes or box structures carrying water under a road. They are counted when they are longer than 20 feet measured along the road, which is why culverts are the second most common structure type.
Good, fair and poor
Inspectors rate three main components of a bridge (the deck, the superstructure that supports the deck, and the substructure that supports everything) on a scale from 0 to 9. For a culvert, the culvert itself is rated instead. The overall condition is set by the lowest of these ratings:
- Good: lowest rating of 7, 8 or 9.
- Fair: lowest rating of 5 or 6.
- Poor: lowest rating of 4 or below.
A poor rating means significant deterioration that needs attention. It does not mean the bridge is unsafe: unsafe bridges are closed or posted with load limits, which the inventory records separately and which each bridge page shows.
Component ratings
| Rating | Label | Meaning |
|---|---|---|
| 0 | Failed | Out of service and beyond corrective action. |
| 1 | Imminent Failure | Major deterioration or section loss present in critical structural components. Bridge is closed to traffic but corrective action may put it back in light service. |
| 2 | Critical | Advanced deterioration of primary structural elements. Bridge may be closed until corrective action is taken. |
| 3 | Serious | Loss of section, deterioration, spalling or scour have seriously affected primary structural components. |
| 4 | Poor | Advanced section loss, deterioration, spalling or scour. |
| 5 | Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| 6 | Satisfactory | Structural elements show some minor deterioration. |
| 7 | Good | Some minor problems. |
| 8 | Very Good | No problems noted. |
| 9 | Excellent | No problems noted. |
| N | Not Applicable | This component does not exist on this structure. |
Other figures
Average daily traffic is the state's most recent count or estimate of vehicles crossing per day.Operating and inventory ratings are load capacities: the inventory rating is the load the bridge can carry indefinitely, the operating rating the maximum permissible load. Scour describes how vulnerable the foundations are to erosion by flowing water. Lengths are reported in metres in the inventory and shown here in feet with the metric value alongside.
Accuracy
Everything shown is as reported by the states to FHWA. Names come from the "facility carried" and "feature intersected" fields, which are free text entered by inspectors, so spelling and abbreviations vary. Coordinates are occasionally wrong in the source data. Nothing here should be used to judge whether a bridge is safe to cross; that is what posting signs and closures are for.
Source
FHWA National Bridge Inventory downloads,2025 delimited "all states" file. The data is a US government work and is in the public domain.