Two weeks ago, we published a report describing the reasons behind the reduction in train speed around Berri-UQAM station in Montreal that has baffled passengers.

Many had noticed that STM vehicles reduce speed in their approach of the popular central station. The measure is clearly different from normal deceleration. But the STM had, apparently, not released an explanation.

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TL;DR Despite claims from the STM, part of the track between Champ-de-Mars and Berri-UQAM station is still susceptible to the force of Azur train cars. The trains reduce speed to "protect the people" and prevent issues like those that shut down part of the Orange line in 2017.

We contacted an STM employee who explained that there are two reasons for the slower speeds. First, on the Green line, it is an effort to mitigate air displacement around Beaudry station, where crews are hard at work to renovate the aging structure. Tunnel gusts, for which the STM network is famous, pose a safety risk to those workers.

However, on the Orange line, we were told, the speed reduction is a precautionary measure to prevent "major" mechanical issues like those that shut down a huge swath of the line in 2017. 

Many will remember when in January of that year the then-new Azur metro cars damaged part of the track. The trains' "contact shoe," which comes into contact with the rail that supplies the train with electricity, had apparently torn a piece of equipment.

In response, and to protect passengers, the STM stopped service between Lionel-Groulx and Côte-Vertu. The Azur trains were also temporarily taken out of service.

The STM employee explained that the slowdown around Berri-UQAM was a precaution to prevent a similar situation.

Our article's title claimed that Azur trains slow down around Berri-UQAM because they "don't quite fit on the tracks," a shorthand MTLBlog used to describe the same phenomenon in 2017.

The STM, however, hotly contested those claims. A representative stated that it was "false" to equate the current problem with that in 2017. This was, instead, "a specific problem at Berri-UQAM" where an old "piece of track equipment [...] needs to be replaced."

However, we reached out to another STM employee who again directly related the current speed reduction to problems with Azur metro cars in 2017.

There is a risk that Azur metro cars could again damage part of the track. While we originally stated that electrified "third rail" was most imperiled by the force of the Azur contact shoe, we now know that it is actually rolling track that is most at risk.

"We've had problems with the Azur trains," the employee stated. Last year, "around the Plamondon metro station, the new train ripped equipment off the tracks."

"We had to adjust certain things and we're pretty sure we have everything okay. But we're not 100% sure," they continued. "The [Azur] train still makes a bit of noise" between Champ-de-Mars and Berri-UQAM stations.

"To protect the people [...] we've reduced speeds."

The "adjustments" to which the employee refers could be the fix to the Azur contact shoe, which an STM employee told us over email were completely corrected "when they were replaced and after the correction of small portions of the métro tracks." Those "adjustments" could also refer to changes to the track.

In sum, the problem does not seem limited to old track equipment. In fact, the force with which the Azur trains come into contact with the track is also an issue.

There are still unanswered questions, however. Most notably: how this piece of the track became damanged in the first place. We are told that Azur speed reductions are in place to "prevent further damage," implying that there is already existing damage.

We also do not know when this issued will be resolved.

Stay tuned.