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Why don't bridges ever get lonely? Because they're always making connections.
over WATER DORCHESTER BAY
.2 MI E OF I 93
Parametric wireframe generated from real NBI dimensions. Drag to rotate, scroll to zoom.
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This bridge has a Poor overall condition rating of 4 out of 9. This bridge is classified as being in poor condition, meaning one or more structural components have significant deterioration. Poor condition does not mean the bridge is unsafe to drive on, but it does mean repairs or replacement may be needed.
The bridge carries 78,900 vehicles per day and is 99 years old (reconstructed in 1978).
Its sufficiency rating of 37.3 places it below the national average of 63.6.
The NBI records a navigation clearance of 12 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 460 feet long — a short crossing, about 10-15 seconds.
A movable bridge — it may occasionally stop for boat traffic.
About 12 feet above ground — standard overpass height.
About 78,900 vehicles cross daily — heavy traffic, congestion likely during rush hours.
The deck is 90 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
1927
99 years old (rebuilt 1978)
Structure Type
Steel Movable (Bascule)
Total Length
460 ft
140.2 m
Deck Width
90 ft
27.4 m
Spans
1
sections between supports
Max Span
67 ft
longest unsupported section (20.4 m)
Traffic Lanes
6 lanes
Two-way traffic
Clearance Below
12 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
78,900vehicles/day
42.30391°N, 71.04783°W
Steel Movable (Bascule)
A movable bridge can change position to allow passage of boats or other traffic. Steel movable bridges include lift, bascule (drawbridge), and swing types.
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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.