Montreal

REM developer to reduce train noise with new measures

CDPQ Infra presented a report on noise levels and mitigation measures in response to residents who live near the tracks complaining about noise pollution.

Work will mean reduced hours for REM users

A train on a light rail system moves between stations.
The CDPQ Infra report identifies rolling and rumbling noises as the main sources of loudness. (Christinne Muschi/The Canadian Press)

The developer of the Réseau Express Métropolitain says it will put in place noise-mitigation measures this fall to lessen disturbances from Montreal's new light rail system.

The measures are expected to cost less than $10 million.

Jean-Marc Arbaud, CEO and president of CDPQ Infra presented Monday a report on noise levels and noise-mitigation measures, following weeks of complaints from residents who live near the Réseau Express Métropolitain (REM) tracks.

When the REM became operational in Montreal's Griffintown neighbourhood this summer, some residents raised concerns about noise pollution. 

CDPQ Infra says it will apply acoustic grinding and dynamic absorbers to alleviate rail roughness and rail radiation, which worsen noise emission.

In response to public outcry, the company installed seven sound-level meters near REM tracks between Griffintown and Nuns' Island over several weeks and recruited specialists in railway acoustics to assess the system.

Sound modelling data was higher than expected in some areas, the report showed.

For instance, on Olier Street in Griffintown, ambient noise with the REM was 60/61 dBA, over a 24-hour period, compared to 55/56 dBA without the light rail system. A level of 60 dBA is about equal to the sound of a normal conversation nearby.

Depending on the area, noise barriers would have little or no effect on reducing loud sounds because of the height of the barrier and where it could be placed, Arbaud said.

The report identifies "rolling noise" from the wheels, rails and platform as well as a "rumbling noise," which stems from the train's overhead structure, as the main sources of loudness.

Noise-mitigation measures will be deployed from mid-October to December. The work will take place overnight, Thursdays through Sundays, meaning the REM will shut down early — at 10 p.m.

WATCH | CBC's Kwabena Oduro answers your REM questions:

Your REM questions answered

1 year ago
Duration 2:40
What caused the delays this week? When will the REM connect to the airport? Kwabena Oduro answers your questions.

With files from Mélissa François