The TTC has announced its entire Line 3 Scarborough RT will remain out of commission for days following a derailment on Monday evening that left dozens injured.

Monday's Line 3 derailment occurred at 7:30 p.m. after the rear car disconnected from a train just outside of Ellesmere station.

In the immediate aftermath of the derailment, the TTC closed the entire line and deployed 20 shuttle buses. On Tuesday morning, the TTC announced that this closure would continue for days.

As previously mentioned, Line 3 SRT will be replaced by dozens of buses for frequent service until it is safe for us to resume train service. External reviewers coming in to assist.
But this could be several days at minimum so we have staff on scene to assist with options. 1/2

— TTC Media Relations 📰🚌🚋🚈 (@TTCNewsroom) July 25, 2023

During what could prove to be an extended closure, Metrolinx is offering commuters the option to use GO Transit service for the cost of TTC fare at nearby stations.

2/2 @GOtransit protocol in place meaning you can ride GO on a TTC fare at Milliken, Agincourt and Kennedy on the Stouffville Line and Scarborough and Eglinton on the Lakeshore East Line as alternatives.

— TTC Media Relations 📰🚌🚋🚈 (@TTCNewsroom) July 25, 2023

The response to the derailment has been met with criticism, including the rollout of replacement shuttle buses.

News of the accident comes just under four months before the permanent closing of Line 3, which will be replaced by a shuttle bus service until the Scarborough Subway Extension opens, currently scheduled for 2030.

Grassroots transit user group TTCriders, notes that the TTC deployed under one-third of the buses it has acknowledged will be required to replace Line 3 service.

"To replace the current RT service in the interim, 70 replacement buses per hour are required during rush hour," reads a statement from TTCriders.

"The TTC dispatched only 20 shuttles on Monday night, which is nowhere near enough to meet Scarborough's needs."

The group notes in its statement that the TTC has not yet completed the Kennedy Station bus bay upgrades needed to accommodate this 70-bus service, but argues that there are immediate moves that can be made to re-instill Scarborough transit users' confidence in the network.

TTCriders calls for City Council to immediately move forward with an approved plan for red-painted bus-only lanes to keep the temporary shuttle service moving. The group also calls on the provincial government to immediately fund free TTC-GO transfers and commit to funding a busway using the current Line 3 corridor.

Perhaps most importantly, TTCriders calls for a thorough investigation of the incident, seeking a report on unfunded gaps in the TTC's State of Good Repair program "and what the TTC will do to ensure a derailment never occurs again."