Hydro One plays an important role in delivering electricity to your community by supplying power to Toronto Hydro and its customers. We are planning to begin construction to upgrade existing underground transmission cables that provide power to Toronto’s downtown core later this year. Originally built in the 1950s, the underground cables located between our Esplanade Transformer Station (TS) and Terauley TS are reaching their end of life and will be replaced to ensure that we continue to energize the city’s most crucial institutions.
The map below shows the tunnel route selected for the new cables through the Class Environmental Assessment (EA) process completed for the project in June 2020. The new underground tunnel will run between the stations at a depth of approximately 25 metres below ground in bedrock within existing road allowances.
In addition to the installation of the new tunnel, new tunnel access shafts will be constructed at both Esplanade TS and Terauley TS. During the Class EA process, we communicated that a mid shaft would also be required near the intersection of Sherbourne Street and Shuter Street. We have now completed the design process and determined that the mid shaft is no longer required and will not be built.
Map showing new underground tunnel route:
Click to enlarge (.PDF)
Pending project approvals and permits, construction is planned to begin by the end of 2021 and be completed in 2025.