Analyzing deck conditions, superstructure ratings, and bad puns...
Analyzing deck conditions, superstructure ratings, and bad puns...
Crunching the numbers on America's infrastructure...
over WATER MYSTIC RIVER
BIG MYS LOWER
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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 42,492 vehicles per day and is 76 years old.
Its sufficiency rating of 58.5 places it below the national average of 63.6.
The NBI records a navigation clearance of 135 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 has some features that may be challenging for travelers with bridge anxiety. See the tips below for a more comfortable crossing.
This bridge is 1524 feet long — a moderate crossing, about 30 seconds.
A truss bridge — the steel framework can provide a sense of enclosure.
About 135 feet above ground — a high bridge with significant elevation.
About 42,492 vehicles cross daily — moderate traffic, some congestion possible.
The deck is 42 feet wide with 2-3 lanes — moderate width.
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
1950
76 years old
Structure Type
Steel (Continuous) Truss (Thru)
Total Length
1,524 ft
464.5 m
Deck Width
42 ft
12.7 m
Spans
3
sections between supports
Max Span
801 ft
longest unsupported section (244.1 m)
Traffic Lanes
3 lanes
One-way traffic
Clearance Below
135 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
42,492vehicles/day
42.38510°N, 71.04729°W
Steel (Continuous) 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.