Metro Line Update: new signalling system taking shape

The new rainbow crosswalk along 104 Ave downtown does important work, helping pedestrians safely get to the other side of 109 St on the MacEwan University campus. It also does vital City Plan work.

The City of Edmonton is digging in on the signalling system for the Metro Line LRT.

Construction and installation of the new system will begin soon and take about a year. Edmontonians will start to see crews cutting concrete and installing wheel detectors, axle counters and other equipment on the tracks between MacEwan and NAIT stations.

“This is a major step towards replacing the incomplete Thales signalling system we’ve been using since the Metro Line opened in 2015,” said Bruce Ferguson, Branch Manager of LRT Expansion and Renewal. “The Metro Line will continue to operate safely while this work is completed and then tested.”

Construction may cause minor changes to bus and LRT schedules. The City will share advance news of any disruptions.

Signals (and how we got here)

A signalling system controls train traffic. It is responsible for tracking train movements, preventing collisions and keeping trains on schedule. The signalling system also manages intersections by triggering traffic signals, sounding warning bells and lowering gates so people can move through intersections safely and as efficiently as possible.

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The City originally planned to use a Communications-Based Train Control (CBTC) signalling system for the Metro Line. CBTC train computers report to a central computer, overseen by ETS staff, to pinpoint the exact location of each train and adjust the speed, spacing and routing of trains. At the time, the City thought the CBTC system was the best way to tighten up train spacing downtown where the Capital and Metro lines share the same set of tracks.

The contractor (Thales) was unable to complete the system. The City opened the Metro Line with an incomplete Thales signalling system in September 2015 by placing speed and other restrictions on trains to keep everyone safe.

The City terminated Thales last spring, and is now involved in legal proceedings to recover costs.

The plan ahead

Alstom was hired in the spring to design and install the alternative to the Thales CBTC signalling system.

The alternative uses a signalling technology called fixed-block.

A fixed-block system has been used on the Capital Line since it opened. It controls trains based on sections of track called blocks. Each block is protected by signals that prevent a train from entering an occupied block.

Alstom is extending the fixed-block signalling system onto the Metro Line. This system will offer a reliable service without needing manual interventions like slower speeds, which is currently necessary with the incomplete Thales signalling system.

The City has found a way to tighten up train spacing using this tested technology so Metro Line trains can share the same tracks with Capital Line trains downtown.

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Thank you to everyone, no matter your mode of travel, for your patience. In all of the changes, one fact hasn’t changed: The City is committed to providing a consistent and reliable service that meets the transportation needs of Edmontonians.

For more information on the Metro Line LRT to NAIT, visit