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

  • Croatia: Peljeski Bridge decision in summer 2017
    November 21, 2016
    Croatia’s minister of infrastructure, Oleg Butkovic, said a winner will be chosen to build the controversial Peljeski Bridge on the Adriatic Sea coast by summer 2017. The project, valued at around €370 million, will be carried out in three phases. In June, a tender was started by the national roads company Hrvatske Ceste but was halted last month over complaints by some bidders about pre-qualification issues. The State Commission for Control of Public Ordering recently rejected the pre-qualificatio
    Read More
  • Tappan Zee takedown into the Hudson River
    January 17, 2019
    A controlled explosion demolished the eastern span of the old cantilever Tappan Zee Bridge across the Hudson River near New York City. The bridge, nearly 5km long, was opened in 1955 to carry traffic between the southern New England area and other regions west of the Hudson. Around 140,000 vehicles used the bridge daily. But the old bridge had deteriorated substantially and would have been too expensive to maintain or keep open for lighter traffic use. It became redundant after the new bridge of the
    Read More
  • Bold move aids Ironton-Russell bridge works in U.S.
    January 24, 2014
    The bold decision to go against the norm and build the back spans using falsework for the Ironton-Russell replacement bridge between Parkersburg, Kentucky and Cincinnati, Ohio allowed land access to build the main span which, along with the first use in the U.S. of precast stay anchor blocks, meant the new structure could get built.
    Read More
  • Tees Valley crossing project consultation nears an end
    May 9, 2019
    Public consultation is nearly closed for a possible new crossing across the River Tees in northern England that could cost upwards of €350 million. A €230-290 million Tees Viaduct Capacity Enhancement project is the preferred option against a €350 million Tees Viaduct option, according to the recently created Tees Valley Combined Authority, the local government. Capacity Enhancement project would see a two-lane bridge built parallel to the existing A19 viaduct to carry traffic travelling northbound an
    Read More

Highlighted Content