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

  • Highway 99 revisited
    March 6, 2024
    David Arminas recently returned to Seattle for an inside look at some of the features of the now-complete SR99 tunnel that was a World Highways key project report in November 2017.
    Read More
  • India’s capital highway project will improve transport connections
    October 10, 2017
    Huge numbers of construction machines as well as plant and equipment are working overtime, backed by mammoth manpower, to meet the targeted completion deadline of March 2018 for India’s Eastern Peripheral Expressway (EPE). The 135km arterial route is being built with six lanes and surrounds India’s National Capital, Delhi, its National Capital Region (NCR) and the industrially developed North Indian states of Haryana and Uttar Pradesh.
    Read More
  • ARTBA concerned over drop in US highway spending
    March 4, 2013
    Despite the 2012 passage of the US federal surface transportation law, known as MAP-21, the real value of highway and bridge contract awards over the last 12 months was down 3% compared the previous 12 month period. This is according to the latest analysis of McGraw-Hill Dodge data by the American Road & Transportation Builders Association (ARTBA). Taking into account changes in wages, materials and inflation, state and local governments awarded US$54.3 billion in real highway and bridge contract awards bet
    Read More
  • The Mersey Gateway bridge project continues on schedule
    October 18, 2016
    Work continues on the 2.3km Mersey Gateway signature bridge project close to Liverpool in the UK. David Arminas reports on some of the construction highlights. Under construction is a cable-stayed structure with three towers that will span the Mersey River’s expansive mud flats between the towns of Runcorn and Widnes near Liverpool. Including the approach viaducts on each side, it will be 2.3km long with a river span of 1km. The main bridge deck will be reinforced concrete. The 80m-high central tower will b
    Read More

Highlighted Content