Crunching the numbers on America's infrastructure...
Crunching the numbers on America's infrastructure...
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over COMB MERRIMAC ST & MBTA
.32 KM S MERRIMAC 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 96,595 vehicles per day and is 64 years old.
Its sufficiency rating of 58.2 places it below the national average of 63.6.
The NBI records a navigation clearance of 23 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 391 feet long — a short crossing, about 10-15 seconds.
A standard overpass design with solid barriers on each side.
About 23 feet above ground — moderate height, similar to a 3-5 story building.
About 96,595 vehicles cross daily — heavy traffic, congestion likely during rush hours.
The deck is 95 feet wide with multiple lanes — easy to stay in a center lane.
This bridge crosses over land, not water — no water views 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
1962
64 years old
Structure Type
Steel Stringer/Multi-beam/Girder
Total Length
391 ft
119.2 m
Deck Width
95 ft
29.0 m
Spans
6
sections between supports
Max Span
103 ft
longest unsupported section (31.3 m)
Traffic Lanes
6 lanes
Two-way traffic
Clearance Below
23 ft
navigation clearance under deck
Clearance height compared to familiar objects
Height shown is the navigation clearance below the bridge deck. The total height of the bridge structure (including towers and superstructure) may be higher.
Daily Traffic
96,595vehicles/day
42.70365°N, 71.13989°W
Steel Stringer/Multi-beam/Girder
A steel stringer bridge uses parallel steel beams (stringers) to support the deck. This is one of the most common bridge types in the US, valued for its simplicity and strength.
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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.