Significant constraints for a 3rd bridge to the east between Quebec and Lévis

Building a third bridge to the east between Quebec and Lévis, as the CAQ is now considering, would come with its share of constraints, according to the numerous studies that the government already has. By favoring the eastern corridor analyzed by CDPQ Infra in its report on mobility, François Legault brings back the 3^e link in the same sector where he had promised to do so in 2018, where different scenarios were studied by the Quebec-Lévis tunnel project office.

• Read also: The CAQ is embarking on the creation of a 3rd link

Incompatible with the urban boulevard

According to the Caisse report, the Eastern corridor is located on the south side, between Monseigneur-Bourget and Lallemand roads. A third link erected at this location would connect Highway 20 in Lévis to Boulevard des Chutes in Quebec over a distance of approximately 8 km, at the intersection of the Dufferin-Montmorency highway.

In its report, CDPQ Infra, however, writes in black and white that a connection to Boulevard des Chutes or Boulevard Montmorency would be “incompatible with the project to transform the Dufferin-Montmorency highway into an urban boulevard.”

However, the CAQ is firmly committed to converting this highway, built in the 1970s in sensitive ecological and aquatic environments, into an urban boulevard. At the time, the scandal of the highway project on the Beauport flats was such that it contributed to the creation of the Bureau d’audiences publique du l’environnement (BAPE). This was also his first mandate, in 1979.

At the beginning of April, the minister responsible for the National Capital, Jonatan Julien, revealed the winners of the idea competition he had launched for phase 4 of the Samuel-de-Champlain promenade. “Phase 4 is impossible without the urban boulevard. If we don’t think about that, let’s stop working on it, friends,” declared Mr. Julien at a press conference.

A challenge for cruise ships

The Inter-Rives Mobility Group (GMI), selected by the 3rd Link Project Office to carry out the opportunity study for the Quebec-Lévis tunnel project, also looked into the possibility of building a bridge in the corridor. from the east.

If the tunnel option had been recommended, it was among other things because the bridge scenario obtained a score of zero with regard to its impact on the waterway.

A bridge could represent a threat to the cruise ship industry, which generates more than $100 million in economic benefits per year in Quebec.

“A bridge in the southern channel of the intervention zone would become the first “obstacle” to navigation coming from the Atlantic Ocean and would limit access to important areas such as the Port of Quebec for the transport of goods and the Old Quebec for cruise ships,” wrote GMI in April 2019.

To continue allowing the Queen Mary 2 to travel to Quebec, a vertical clearance of 74 meters is required, according to this study.

To give an idea, the vertical clearance of the Quebec Bridge is 45 meters, while the main span of the new Champlain Bridge is located at a height of 38.5 m above the level of the St. Lawrence. The bridge proposal south of Île d’Orléans unveiled Monday by Éric Duhaime provides for a clear height of 49.5 meters.

Environmental impacts

Of the three distinct new link routes for the Île d’Orléans bridge reconstruction project analyzed by GMI in 2019, the option of a bridge obtained neither a passing grade on the environmental level (29%) nor economically (44%).

In its very recent report, CPDQ Infra also raises the environmental constraints represented by the presence of wetlands of interest and protected areas (areas of concentration of aquatic birds) on the Beauport flats. Same thing on the south side, in the Martinière sector, where there is a large regional park, larger than the Plains of Abraham, and “wetlands and forests of interest”.

Generally speaking, on the possibility of adding an inter-river road link, CDPQ Infra emphasizes that the Eastern Corridor also presents insertion constraints due to the depth of the St. Lawrence River, the presence of wetlands, heritage sites and agricultural areas.

Displacement of congestion

The Caisse also raises issues regarding the capacity of the road network to absorb the traffic that would be generated on either side of a possible inter-river link.

She estimates that “the time savings on existing bridges would be low”, i.e. 5 minutes on average.

“Taking into account the very significant integration constraints, the analyzes carried out point to a shift in congestion, and not to the desired improvement in mobility. For these reasons, CDPQ Infra does not recommend the creation of a new inter-river road link,” we can read in the report unveiled on Wednesday.