Thorold, Main Street and Townline Tunnels under Welland Canal

Thorold: (Satellite)

East Main: (Satellite)

Townline: (Satellite)

The Thorold Tunnel was built in 1967. The East Main Street and Townline Tunnels were built in 1973 when the Welland Canal Bypass was built.

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Thorold Tunnel

 This tunnel replaced Bridge #7 and Bridge #9.

brocku
"Construction of the Thorold tunnel began in 1965 and was completed in 1967....The tunnel replaced two bascule bridges (Bridge 9 at Ontario Paper Co. and Bridge 7 at Peter Street) that carried traffic over the canal."

Street View, West Portal

Street View, Apr 2021

Mar 2025:

City of Thorold posted

Thorold Tunnel Closures 🚧 from Monday, April 14 to Monday, July 7, 2025

MTO will start with one Westbound lane closure in the north tube. There will be a full closure of the Westbound lanes in the north tube in the evenings from 8:30 p.m. to 5:30 a.m.

The full closure Westbound traffic will be redirected to: Davis Road (Highway 58) > Lundy's Lane (Highway 20) > Hwy 406

Sorry for any inconvenience during this construction project.

Learn more

https://bit.ly/4hsBwKD

The detour sends the traffic to Allanburg Bridge. I did some Googling to find out what the construction is doing. The most I could find is that it is "another maintenance phase." They closed the eastbound lanes last year. [ThoroldToday]

Road Map

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East Main Street Tunnel

I took a distant view of the portal in an effort to capture how they dug a canyon to go under the surface level canal.

Street View, East Portal 

I learned about the location of these tunnels while doing more research on the Welland Canal. I knew that a road went under the Welland Canal because I have seen photos of ships going over the road. But I had not saved any of those photos. Then today I came across this photo. I know this ship is headed upbound so we are looking at the west portal. That is why I got the east portal with the above street view.

Bobby Dzz via Dennis DeBruler

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Townline Tunnel

On the right side of the barrier in the center is a railroad.

Street View, West Portal

Since the Main Street and Townline tunnels were built as part of the Welland Bypass project, they could use the relatively simple cut-and-cover construction technique. [dbpedia]

A Google search offers some YouTube drive through videos. Or you can play with the street view links above to do virtual drive throughs.