A thousand birthday greetings for US-Canada Thousand Island Bridge

The Canada-US Thousand Island Bridge system celebrated its 80th birthday in August with presentations and an open house at its US headquarters. The 33.7km three-bridge system over the St Lawrence River took 16 months to build and was completed 10 weeks ahead of schedule. It runs from Collins Landing near Alexandria Bay in the US state of New York to the small town of Ivy Lea in the Canadian province of Ontario. The system connects US Interstate 81 and Canada’s Highway 401, a major motorway between Montre
August 21, 2018 Read time: 2 mins
The Canada-US Thousand Island Bridge system celebrated its 80th birthday in August with presentations and an open house at its US headquarters.


The 33.7km three-bridge system over the St Lawrence River took 16 months to build and was completed 10 weeks ahead of schedule. It runs from Collins Landing near Alexandria Bay in the US state of New York to the small town of Ivy Lea in the Canadian province of Ontario. The system connects US Interstate 81 and Canada’s Highway 401, a major motorway between Montreal and Toronto, ending in Windsor on the Ontario border with the US state of Michigan.

The 1,370m crossing over the American channel of the river - from the US mainland to Wellesley Island - consists of a suspension bridge with a main span of around 245m and nearly 46m of clearance above the river.

The Canadian crossing includes the 183m continuous Warren Truss span connecting Hill Island to Constance Island, a steel arch of 106m spans from Constance Island to Georgina Island and a suspension bridge of 229m from Georgina Island to the Canadian mainland. The Canadian span from abutment to abutment is 1,015m and the suspension span provides 37m of river clearance.

The boundary at the International Rift boundary – the channel between Wellesley Island and Hill Island - is bridged by two parallel 27.4m rigid-frame arched spans of reinforced concrete with masonry facing. Originally there was only one bridge at boundary but due to increased traffic it was twinned in 1959.

Operation of the Thousand Islands Bridge system is shared under a joint agreement that created the US based Thousand Islands Bridge Authority which estimates that there are 2,000 vehicle-cross the annually. The system’s original consulting engineer was Robinson and Steinman of New York City that  continues to do so today but as 3220 Parsons Transportation, notes the authority.

Road Structures

For more information on companies in this article

Related Content

  • PPRS Nice 2018: maintenance moves mountains
    June 22, 2018
    Strategic maintenance was a major theme at the second Pavement Preservation and Recycling Summit in Nice, France. The world is changing, mobility is changing and so roads must change and adapt for the future.” With this brief statement, Jacques Tavernier opened the second PPRS Summit. “At the same time there is a growing awareness of poor or non-existent maintenance for highways. The question for this conference is how to adapt road maintenance in the face of this challenge,” said Tavernier, in his role as
    Read More
  • Consultation soon for Vancouver area’s Massey Tunnel replacement
    September 19, 2019
    The Canadian province of British Columbia could put options for a Massey Tunnel replacement out to consultation late this year or early next. A statement from the BC ministry of transportation and infrastructure said the government is in discussions with various stakeholders about which options it will put out for consultation. Whatever option is chosen to replace the ageing four-lane Massey Tunnel – be it a bridge or another tunnel – it will be will be either six or eight lanes, according to the gove
    Read More
  • Second Tees Valley Viaduct proposed at Middlesbrough
    March 19, 2019
    Proposals for a second crossing over the Tees River in northern England have gone out to public consultation, according to media reports. The Tees Valley Combined Authority, the local authority, said there are two options to take the A19 trunk road over the River Tees at the city of Middlesbrough. One plan, costing between €235-292 million, would be for a bridge parallel to the existing one where each bridge would traffic in only one directions. The other option is for a four-lane €350 million brid
    Read More
  • Flatiron wins Winnipeg interchange project in Canada
    August 5, 2015
    US-based contractor Flatiron has won a US$157 million design and build contract for an interchange in the Canadian city of Winnipeg, in the province of Manitoba. The project, for owner Manitoba Infrastructure and Transportation, will replace the existing loop-ramp interchange for Provincial Trunk Highways 59 and 101. Work includes seven precast girder bridges between 40m and 100 meters in length, one cast-in-place box culvert through-pass, construction of 1.5 million cubic meters of interchange embank
    Read More

Highlighted Content