Bridges: the original social network. Connecting communities since 850 BC.
Bridges: the original social network. Connecting communities since 850 BC.
Did you know? The oldest bridge in the NBI was built in 1697.
over GALLATIN RIVER
DURNAM BRIDGE
Parametric wireframe generated from real NBI dimensions. Drag to rotate, scroll to zoom.
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This bridge has a Fair overall condition rating of 5 out of 9. While it is not classified as structurally deficient, it shows some deterioration that is being monitored.
The bridge carries 99 vehicles per day and is 56 years old (reconstructed in 1995).
Its sufficiency rating of 39.8 places it below the national average of 63.6.
For travelers with bridge anxiety
This bridge may cause some awareness for travelers with bridge anxiety, but has manageable characteristics.
This bridge is 76 feet long — a quick crossing, under 5 seconds at highway speed.
A truss bridge — the steel framework can provide a sense of enclosure.
No height data available — likely a standard overpass height.
Only about 99 vehicles cross daily — very light traffic with low congestion risk.
The deck is 18 feet wide with 1-2 lanes — a narrower crossing.
This bridge crosses over water. Focus on the road ahead — the water is far below.
This comfort score is designed to help individuals with bridge anxiety plan their travel. All bridges in the National Bridge Inventory are regularly inspected and deemed safe for travel. This is not medical advice — if you experience severe anxiety, please consult a healthcare professional.
Year Built
1970
56 years old (rebuilt 1995)
Structure Type
Steel Truss (Thru)
Total Length
76 ft
23.2 m
Deck Width
18 ft
5.5 m
Spans
1
sections between supports
Max Span
76 ft
longest unsupported section (23.2 m)
Traffic Lanes
1 lane
Daily Traffic
99vehicles/day
45.32366°N, 111.17511°W
Steel Truss (Thru)
A steel truss bridge uses a framework of interconnected triangular elements. The geometric rigidity of triangles makes this design extremely efficient at distributing loads.
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Data from the National Bridge Inventory (NBI), maintained by the Federal Highway Administration (FHWA).
Data year: 2025. Conditions may have changed since the last inspection.
This information is provided for educational and informational purposes only. It should not be used as the sole basis for any decisions related to bridge safety or transportation planning. Always consult official sources and local authorities for the most current data.