Minnesota Department of Transportation

511 Travel Info

Historic Bridges

Approach Span for Ore Dock #6 (Bridge 69833)

Approach Span for Ore Dock #6 (Bridge 69833)

Approach Span for Ore Dock #6
See features of the bridge

History & significance

Bridge 69833 is part of the Duluth, Missabe & Northern Railway / Duluth, Missabe & Iron Range Railway Ore Dock No. 6 Approach located in Duluth, St. Louis County. Constructed by the DM&N in 1917-1918, the DM&N / DM&IR Ore Dock No. 6 Approach is a multi-span, riveted steel deck girder structure that historically carried the DM&N / DM&IR Mountain Iron to Mesabi Junction (Duluth) line over several city streets in Duluth, to the Ore Dock No. 6, which is sited in the St. Louis Bay of Lake Superior. Bridge 68933 was designated in 1966-1967 after spans 46-48 were modified to accommodate the construction of Interstate 35 beneath them. The modification included replacing Bents 46 and 47 with a single bent, replacing Span 47 with new girders, and installing a drainage pan under the spans and a chain link railing along each side of the deck. The lower portions of Bents 45 and 48 were also encased in concrete. The Ore Dock No. 6 Approach is significant as a contributing resource to the DM&N / DM&IR Mountain Iron to Mesabi Junction (Duluth) railroad corridor. This railroad corridor is significant for the critical role it played in the transportation system that enabled the Mesabi Range to be the leading producer of iron ore in the U.S. for more than 70 years.

Location

City of Duluth (St. Louis County)
Latitude, Longitude: 46.75370204, -92.13720293

Bridge features

Approach Span for Ore Dock #6

DM&N / DM&IR Ore Dock No. 6 at southeast end of approach structure.

Approach Span for Ore Dock #6
Curve in the alignment of the structure.
Approach Span for Ore Dock #6

One in a series of two parallel, steel riveted plate
girder spans now carrying a single deck and supported on riveted, steel two and four-legged bents. Specific superstructure construction features include cross-bracing between the girders. Overpass bridges, including Bridges 7632, 7627, and L6137 (but not 69833) are supported on steel, riveted two-legged bents.

Approach Span for Ore Dock #6
One in a series of two parallel, steel
riveted plate girder spans now carrying
a single deck and supported on riveted,
steel two and four-legged bents.
Specific superstructure construction
features include cross-bracing between
the girders. Overpass bridges, including
Bridges 7632, 7627, and L6137 (but not
69833) are supported on steel, riveted
two-legged bents.