When work crews found water leaking into the new tunnel of the Midtown Power Corridor on Wednesday they were tangling with one of Toronto’s many usually unseen and often underground rivers and creeks. In this case, it was the venerable Yellow Creek which stretches from Yonge Street through the beautiful Avoca Ravine and crosses Mt Pleasant just about where the tunnelling is going on. Mt. Pleasant Road was closed overnight and Toronto Fire Services helped pump out the tunnel. According to Toronto Fire Services district chief Paul Halls, crews had tunneled about 48 metres underground when they ran into trouble. About three-quarters of the way down, minor water leaks were detected. However, technicians were able to inject concrete into the tunnel walls to stop the leak. They continued digging, but ran into a major leak further down, which they were unable to plug with concrete. The Toronto Fire Service was then called to the scene to begin filling the tunnel with water — a technique used to reduce pressure and prevent a collapse. Once the water rises to the level of the leak, pressure coming in from the leak subsides and the tunnel walls typically stabilize.d The Yellow Creek is on an important nature walk through what is known as the Park Drive Reservation. It has been closed to the public since 1973. and was used to access the network of roads in the Don valley prior to construction of the Don Valley Parkway and the extension to Bayview Ave. The picture is courtesy of rudy.ca and shows the Yellow Creek at it’s most picturesque. and non-threatening. City of Toronto, CTV, Rudy.caMt Pleasant closure caused by the Yellow Creek
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When work crews found water leaking into the new tunnel of the Midtown Power Corridor on Wednesday they were tangling with one of Toronto’s many usually unseen and often underground rivers and creeks. In this case, it was the venerable Yellow Creek which stretches from Yonge Street through the beautiful Avoca Ravine and crosses Mt Pleasant just about where the tunnelling is going on. Mt. Pleasant Road was closed overnight and Toronto Fire Services helped pump out the tunnel. According to Toronto Fire Services district chief Paul Halls, crews had tunneled about 48 metres underground when they ran into trouble. About three-quarters of the way down, minor water leaks were detected. However, technicians were able to inject concrete into the tunnel walls to stop the leak. They continued digging, but ran into a major leak further down, which they were unable to plug with concrete. The Toronto Fire Service was then called to the scene to begin filling the tunnel with water — a technique used to reduce pressure and prevent a collapse. Once the water rises to the level of the leak, pressure coming in from the leak subsides and the tunnel walls typically stabilize.d The Yellow Creek is on an important nature walk through what is known as the Park Drive Reservation. It has been closed to the public since 1973. and was used to access the network of roads in the Don valley prior to construction of the Don Valley Parkway and the extension to Bayview Ave. The picture is courtesy of rudy.ca and shows the Yellow Creek at it’s most picturesque. and non-threatening. City of Toronto, CTV, Rudy.ca
