The St. Clair Tunnel
Text from the plaque
This was the first subaqueous tunnel in North America and one of the great engineering feats of the 19th century. Built in 1889-1891 to link the Canadian mainline of the Grand Trunk Railway with Chicago, the tunnel is 1,837 metres long with a 6-metre bore. Joseph Hobson, a Canadian engineer, designed and supervised its construction. His innovative combination of cutting shield excavation, cast iron tunnel lining, and compressed air broke the transportation bottleneck caused here and elsewhere by the impossibility of tunnelling through soft riverbeds.
Transcribed from the marker, not summarised.
Find the place
The County of Lambton
The City of Sarnia
On the north side of St. Andrew Street
between Christina Street South and Vidal Street South
N 42 57.461 W 82 24.614
Recorded June 2009. Check current access before visiting.