St Clair Tunnel
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Hard Oiler
N 42° 57.492 W 082° 24.414
17T E 385247 N 4757133
The first submarine rail tunnel connecting Sarnia, Ontario, Canada with Port Huron, Michigan.USA Completed in 1890, closed in 1994.
Waymark Code: WMAZ4
Location: Ontario, Canada
Date Posted: 04/21/2006
Views: 260
The St. Clair River Tunnel was the first full-size submarine tunnel built in North America. Prior to its completion, a railroad had never been able to pass beneath a river. This accomplishment was not possible until engineers learned to combine three elements of tunnel construction: the shield method of excavating, the cast iron tunnel lining, and excavating in a compressed air environment. The St. Clair River Tunnel is important in the history of engineering because it was the world's first true test of the feasibility of constructing railroad (and later vehicular) tunnels through the soft, porous ground commonly found beneath rivers.
The bore diameter of 19’ 10” could not handle larger freight cars and a new tunnel, 27’ 6” in diameter was opened in 1994 and the old one closed. The picture below shows the old and new side-by-side from the listed coordinates
Various proposals have been made for what to do with the old tunnel – including a bicycle path between the US and Canada however 911 events effectively put such ideas on permanent hold. The tunnel is full of security devices so don’t try and use it – quite a number have tried and haven’t got too far.
