Photo: Source: City of Quebec
The excavation work to build two kilometres of the tunnel to the tram on parliament hill is expected to take three years, reported Friday by the project office.
The tunnel will have a depth of up to 40 metres, with an entrance on the street of the Crown, and an output in the Montcalm district.
The course has also been modified. Rather than passing under the coast of Abraham to reach the place d’youville, he would come under the district of Saint-Jean-Baptiste, to the east of the rue Sainte-Claire and north of the rue Saint-Olivier. This change has explained, aims to reduce the number of curves in the plot earlier and to avoid a too steep slope.
For this is effects on the residents of the district of Saint-Jean-Baptiste in the field of noise and vibration, and they depend particularly on the type of technology used for digging.
The use of the method of drilling by “blasting” can cause vibration and smoke during explosions, so that the use of a “haveuse” (a rotary machine excavation) causes more dust.
As regards the first method, it does not provide for “any vibratory impact” to the buildings in common use, but specific measures will be taken to the height of the Grand Theatre and the INRS, considered to be more fragile.
The use of a tunnel boring machine is practically excluded, because it is too expensive for a tunnel too short.
Two possible courses of action in Montcalm
The presentation was also an opportunity to learn a new scenario was on the table for the portion of the tunnel located in the Montcalm district.
Originally, the tunnel had to be located at the corner of the rue des Érables, but the project office announced on Friday that it was studying also a scenario to make out the tram street Turnbull, is 500 metres away.
This scenario would have the effect of moving the tram on René-Lévesque boulevard at the height of the Cartier street rather than on a mode underground. The consortia participating in the tender will have to submit plans for the following two scenarios.
On Friday, the project office was not yet able to say what could be the impact on traffic and parking in the area. However, the director of the project office, Daniel Genest, has indicated that this aspect will be discussed in the framework of the hearings of the Bureau d’audiences publiques en environnement (BAPE), which must begin on July 6.
The idea of reducing the length of the tunnel in high city stems from budgetary considerations, the project office will have to reduce some investment to meet the target of $ 3.3 billion.
Other details will follow.
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