The noise level of the Réseau express métropolitain (REM) is “unsatisfactory” and “higher” than expected between Île-des-Soeurs and Central Station, according to data collected in recent weeks. CDPQ Infra plans to add noise mitigation measures on certain segments and across the entire network.
“As we have already said, we are not satisfied with the noise caused by the operation of the REM in certain sectors. Over the last few months, we have adopted a structured approach, accompanied by international experts, to make a diagnosis which now allows us to implement proven solutions. These will be subject to rigorous monitoring in order to validate the achievement of our noise reduction objectives,” said Jean-Marc Arbaud, President and CEO of CDPQ Infra, during a briefing. press Monday morning.
Seven sound level meters, allowing the impact of the REM to be measured continuously, were installed in residential areas of Nuns’ Island, Pointe-Saint-Charles and Griffintown, indicates CDPQ Infra.
“The data collected indicates different situations from one sector to another. Griffintown and Nuns’ Island present higher measurements than those produced by the initial modeling,” specifies the promoter of the REM, this electric train which connects the DIX30 district, in Brossard, to the Central Station.
“There is always a necessary phase of adaptation and rectification,” added Jean-Marc Arbaud. He noted that similar adjustments occurred in Düsseldorf, Germany, and Sydney, Australia.
Rolling and rumbling
The experts from the SYSTRA firm “concluded that the main sources of noise emissions are the transmission of vibrations by the rail towards the overhead structure which creates a rumbling noise, the contact between the wheels of the cars and the rail which generates a rolling noise”.
They recommended acoustic grinding of the rails and the installation of dynamic absorbers on significant portions of the route, located near homes. The service will be interrupted from 10 p.m. (rather than 1 a.m.) for five evenings per week for the intervention of technical teams. Service interruptions will be announced in advance to allow users to adjust.
“From the beginning of November, acoustic grinding of the rails will be carried out on the entire section between Nuns’ Island and Central Station, then continuing to Brossard station. The dynamic absorbers will be installed gradually, from mid-October until December,” indicated CDPQ Infra.
Hope of local residents
These two measures will result in an expected reduction in total sound intensity of 5 to 10 decibels at the source. In general, such a reduction is equivalent to a drop in the level of noise emitted ranging from 3 to 10 times compared to the current situation, according to CDPQ Infra.
“The good news is they take it seriously. Reducing noise at the source is what we need to do. But I hope they will succeed, because the noise goes around the house,” says Yolande Racine, who lives 500 meters from the tracks, in the Pointe-Saint-Charles district.
“The noise depends on the wind and humidity. Today it’s horrible. It’s very disturbing. And it’s the rush hours that are the most terrible,” adds her partner, François-Marie Bertrand.
He doubts the effectiveness of grinding the rails: “A rail is already as soft as a baby’s face. I wonder what grinding can improve. I don’t understand that one. »
Further details will follow.