Subway service has resumed between Union and Bloor-Yonge stations after a Toronto Hydro substation flooded, cutting off the power to a significant stretch of the Yonge line on Monday morning.

The issue near Richmond and Church streets was discovered at around 5:30 a.m. The initial estimate for the restoration of service was noon, however the TTC was able to restore service ahead of schedule at 8:25 a.m.

“The cables have been spliced, my crews have done a great job to get that done, and service has now resumed,” TTC CEO Andy Byford told CP24 at Bloor-Yonge Station. “I really do appreciate customers’ patience this morning. We will be looking into this with Toronto Hydro to see what happened but job number one is getting people to work. “

According to Toronto Hydro, the issue was related to the failure of TTC equipment inside the substation.

During the closure about 60 shuttle buses were operating along Yonge Street.

Speaking with CP24, Byford said that trains will be travelling at lower frequency through the Union to Bloor-Yonge station corridor as a precaution.

"What we don't want to do is overload the power just as we are getting service back," he said.

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