Parks Canada

Parks Canada

September 28, 2005 12:00 ET

Government of Canada Designates the Construction of the Lethbridge Viaduct as a National Historic Event

LETHRIDGE, ALBERTA--(CCNMatthews - Sept. 28, 2005) - On behalf of the Honourable Stephane Dion, Minister of the Environment and Minister responsible for Parks Canada, the Honourable Anne McLellan, Deputy Prime Minister and Minister of Public Safety and Emergency Preparedness, today announced that the construction of the Lethbridge Viaduct has been designated as a national historic event.

"The Lethbridge Viaduct is an outstanding engineering achievement that overcame the construction challenges presented by its immense size. The construction also had to deal with the strong winds, dry soils, and extremes of temperature in the Oldman River Valley," said Minister Dion. "Today's designation acknowledges the world's largest steel viaduct and we are proud to commemorate its construction as part of our history."

The Lethbridge Viaduct was built in 1907-1909 to shorten and improve the railway line between Lethbridge and Fort Macleod. The Lethbridge Viaduct crosses the Oldman River (formerly Belly River) at Lethbridge, Alberta, on the Crow's Nest Pass branch of the Canadian Pacific Railway.

"We owe it to present and future generations to remember the construction of the viaduct," said Minister McLellan. "The viaduct marked the improvement of the railway line in Alberta. To this day, the viaduct still carries the largest of the Canadian Pacific Railway's modern diesels and freight cars, which are heavier and longer than envisaged by its builders and this alone proves how significant its construction was and continues to be."

In contrast to other high level viaducts of its era, the Lethbridge Viaduct has not required any strengthening or ultimate replacement to meet modern live load demands. The continuance of the Lethbridge Viaduct in service as-built, in spite of increasingly heavy moving loads, the impact of severe wind forces and dramatic temperature changes, is a testament to the excellence of its design and construction.

Today, the Lethbridge Viaduct remains the largest steel tower bridge in the world in its overall length, weight, and uncommon height. It is far longer than any other high level viaduct of its type, and is the only North American viaduct over 90 m (300') in height to remain in service.

Created in 1919, the Historic Sites and Monuments Board of Canada advises the Minister of the Environment on the national historic significance of places, persons and events that have marked Canada's history. It is one means of educating the public about the richness of our cultural heritage, which must be preserved for present and future generations.

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Contact Information

  • Office of the Minister of the Environment
    Brigitte Caron
    Press Secretary
    (819) 997-1441
    Historic Sites and Monuments Board of Canada
    Michel Audy
    Executive Secretary
    (819) 997-0129