The TTC is closing the 2 Bloor - Danforth subway line between Keele and Ossington Stations this evening, Wednesday, October 1, starting at 10 p.m.

While the line is closed, TTC crews will start permanently repairing the subway tunnel that was damaged yesterday Tuesday, September 30, near Dundas West Station.

The TTC will operate more than 50 shuttle buses between Ossington and Keele Stations to replace subway service. It’s assigning customer-service staff to stations across the line to help passengers get to their destinations.

Normal subway service resumes at 6 a.m. tomorrow.

This evening, crews will get the tunnel ready for a final, permanent repair, tomorrow evening Thursday, October 2 during normal maintenance hours after regular service has ended — the TTC doesn’t expect it will have to close the subway early tomorrow. They’ll remove the pile that has punctured the tunnel next week.

In the Globe and Mail, reporter Jill Mahoney described the incident yesterday that lead to tonight’s early closure:

“Part of Toronto’s subway system was shut down for seven hours [yesterday] after a hole in a tunnel created by a Metrolinx contractor shifted overnight, causing water and silt to flood the tracks during the morning rush hour on Tuesday. “The Toronto Transit Commission resumed service between Keele and Ossington stations on the Bloor-Danforth line around 3 p.m. after work crews installed a temporary fix and cleaned up debris. “‘We found [the hole] last week. It’s been perfectly safe to operate. There’s been no movement at all,’ [the TTC’s] chief operating officer Mike Palmer told reporters. ‘Something changed today and groundwater [found] its way through the hole.’ “Thousands of commuters faced long delays and chaos on part of Line 2 after officials closed Dundas West station just before 8 a.m. on Tuesday after water approached the track level, Mr. Palmer said.”

Metrolinx is investigating the circumstances around this incident. Its contractor was working on the Union - Pearson Express project.

According to the TTC, the subway tunnel remains safe, but it must permanently repair it to make sure that water and mud does not intrude into the tunnel again and further disrupt service.

A TTC news release explains that “Although the TTC usually tries to undertake repairs and maintenance during weekends and overnight, this work requires extra preparation time that an early closure affords. Nuit Blanche activities this Saturday commit the TTC to operating uninterrupted subway service throughout the night and into Sunday, leaving this evening as the best option for the early closure.”