What's a bridge's favorite exercise? Cross-fit.
What's a bridge's favorite exercise? Cross-fit.
The average US bridge is 48 years old. That's a lot of birthday candles.
over COMB MERIMAC RIV/ACCESS
AT MERRIMACK RIVER
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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 25,000 vehicles per day and is 108 years old (reconstructed in 1982).
Its sufficiency rating of 60.3 places it below the national average of 63.6.
The NBI records a navigation clearance of 9 feet — the minimum vertical space below the bridge deck. The total height of the bridge structure (including towers, railings, and superstructure) may be higher.
For travelers with bridge anxiety
This bridge may cause some awareness for travelers with bridge anxiety, but has manageable characteristics.
This bridge is 1497 feet long — a moderate crossing, about 30 seconds.
An arch bridge design with some openness to the surroundings.
About 9 feet above ground — standard overpass height.
About 25,000 vehicles cross daily — moderate traffic, some congestion possible.
The deck is 80 feet wide with multiple lanes — easy to stay in a center lane.
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
1918
108 years old (rebuilt 1982)
Structure Type
Concrete Arch (Deck)
Total Length
1,497 ft
456.3 m
Deck Width
80 ft
24.4 m
Spans
7
sections between supports
Max Span
107 ft
longest unsupported section (32.6 m)
Traffic Lanes
4 lanes
Two-way traffic
Clearance Below
9 ft
navigation clearance under deck
Daily Traffic
25,000vehicles/day
42.70335°N, 71.16035°W
Concrete Arch (Deck)
A concrete arch bridge uses a curved concrete structure to transfer loads through compression. Concrete arches are durable and can be very aesthetically pleasing.
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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.