1913 Saint-Laurent RR and 1934+1958+1963 Honoré (Honore) Mercier Bridges over St. Lawrence River at Kanahawake-Montreal, QC

Railroad: (Historic Bridges; Satellite)

Road: (Historic Bridges; Satellite)

There are two pairs of bridges.

First the pair over the South Shore Canal that ends at the St. Lambert Seaway Lock.

Obviously, the railroad bridge.

Street View, Nov 2020

Turning to my right, I see the road bridge.

Street View, Nov 2020

Viewing from the downstream side we get the railroad bridge in the background.

This is a Pennsylvania truss. [HistoricBridges_road]

Street View, Nov 2020

Then the pair over the river.

The railroad bridge.

Street View, Jun 2023

Southbound lanes. The northbound lanes are in the foreground, and the railroad bridge is in the background.

Street View, Jul 2016

The northbound lanes.

Street View, Sep 2024

There was a navigation channel on the south side of the river before the South Shore Canal was opened in 1958, thus all of the bridges have a through truss near the south bank.

Street View, Sep 2024

I could not get a good view of the lift bridge from the road bridge because a pedestrian fence was in the way. TI soon noticed that the fence was designed to discourage suicides.

Street View, Oct 2024

Richard Haydon posted
Train lift bridge at Kanahawake, Quebec. On the South Canal .

1932 construction of the Honoré Mercier Bridge

jacquescartierchamplain, Photo credit: BAnQ
"The bridge was opened to traffic on June 22, 1934, or 10 months before the scheduled completion date. It was originally 1361.25 m [4466'] long. Its main steel arch span was 121.87 m [400'] long, and it had 11 steel spans and 31 reinforced concrete spans."

This construction anticipated that a second bridge would be built across the river to provide 4 lanes of traffic.

jacquescartierchamplain
1958-59: "For the St. Lawrence Seaway construction project, the St. Lawrence Seaway Management Corporation (SLSMC) started work to raise and extend the south section so that ships could pass underneath."

jacquescartierchamplain
1963: The second bridge was built downstream of the 1932 bridge. It is managed by the provincial government, whereas the 1932 bridge is a federal bridge.
"In the provincial bridge, the bridge engineers had to devise an innovative method to erect the bridge piers, given the thick layer of glacier marl over the rock, the river’s depth, and the speed of the current. Since the St. Lawrence River is so deep at this point, the engineers decided not to use cofferdams and instead chose pneumatic caissons, a method that had not been used in Montreal in 25 years."

Government management was changed on Oct 1, 1998.

jacquescartierchamplain

HistoricBridges_road
The original bridge before the Seaway was built.

HistoricBridges_road
Construction of the second navigation span.

"This impressive through truss bridge sits on the location of an earlier famous continuous truss bridge from 1887. The previous bridge was one of the earliest continuous truss bridges ever built. The bridge seen today contains two impressive through truss main spans, and a variety of deck truss spans, some of different span lengths. The bridge serves two tracks and was built as two parallel superstructures, with the second superstructure built in the same place as the previous single track bridge after its demolition, with traffic flowing over the first new superstructure while the second superstructure was built. Thus, railway traffic was not interrupted by construction." [HistoricBridges_rail]

HistoricBridges_rail
"Historical photo showing construction of the current bridge, with the previous bridge visible in the background."

HistoricBridges_rail
"Historical photo showing construction of the previous bridge."

HistoricBridges_rail
Historical photo showing previous bridge.
[So the railroad was the Canadian Pacific. The steamboat reminds me that this was the navigation channel until the Seaway was built.]