Temporary bridge replacement in the US

A temporary bridge structure provided by Acrow Bridge is maintaining traffic flow for a key crossing in Vermont. The bascule bridge is allowing both vehicular and vessel traffic to pass during the reconstruction work to the North Hero-Grand Isle Drawbridge in Vermont. The US$60 million project involves replacing the historic twin leaf bascule bridge on Lake Champlain. This modular steel bascule bridge is allowing transport to continue to and from the Lake Champlain island towns of North Hero and Grand Isl
July 2, 2019 Read time: 3 mins
The temporary, modular steel structure from Acrow Bridge is helping ensure vehicle and vessel traffic can be maintained while a new crossing is built at Lake Champlain
A temporary bridge structure provided by Acrow Bridge is maintaining traffic flow for a key crossing in Vermont. The bascule bridge is allowing both vehicular and vessel traffic to pass during the reconstruction work to the North Hero-Grand Isle Drawbridge in Vermont. The US$60 million project involves replacing the historic twin leaf bascule bridge on Lake Champlain.


This modular steel bascule bridge is allowing transport to continue to and from the Lake Champlain island towns of North Hero and Grand Isle, Vermont. The bridge replacement work was needed due to an increasing number of costly emergency repairs over the last several decades. There had also been difficulty in sourcing parts for repairs.

Built in 1953, the bridge is located on US Route 2, the only connecting passage through the islands and a critical link south to the Vermont mainland. It carries 3,000 cars and trucks/day during the off-season and double that number during the summer and fall months. Without a span in place during construction, a detour of around 100km would result. In addition, the drawbridge allows for sailboats and large motor vessels to pass through the channel between Grand Isle and North Hero and is required by the 7007 US Coast Guard to be opened on a regular schedule and during emergencies between May 15th and October 15th each year. As each missed opening would incur large fines, the Vermont Agency of Transportation (VTrans) deemed a provisional lift bridge critical to the success of the multi-year project.  

Contractors broke ground on the project in July 2018 and continued their work on Acrow’s bascule bridge throughout the winter ensuring a fully functional structure for the first required opening of the season on May 15th, 2019. When the new structure opened, the old bridge was raised for the last time and will be dismantled in the open position so vessel traffic will not be impacted.

The Acrow bridge is 9m wide to accommodate two lanes of traffic. The movable bascule span is 18m long and the back span is 21m long for an overall length of 40m. The back span also includes a pedestrian walkway to allow access to the control cabin. Acrow’s structure is currently scheduled to be in service until May 2021, when traffic will begin to use the new drawbridge. The project completion date is estimated to be 2022.

The project owner is VTrans, with Cianbro Corporation acting as CMGC (construction manager-general contractor) partner. Acrow designed the bascule span, the back span and the mechanical systems of the rental structure, with temporary approach spans design and project engineering by Cianbro. HDR engineering was engaged as a consultant to VTrans.  

“After a number of years of preliminary planning by VTrans, the design process was addressed in a deliberate and collaborative manner so that the bridge opening deadline was successfully met in order to commence the new navigation season,” said Randy Needham, New England regional manager at Acrow. “It has been a pleasure to be a part of this important project, and know that our solution is believed to have cut down on the overall project timeline by a year.”

Road Structures

For more information on companies in this article

Related Content

  • Washington DC’s historic bridge replacement project
    June 11, 2019
    The project to replace a historic bridge in US capital Washington DC is providing major challenges for its builders - Mike Woof writes
    Read More
  • Widening works: road user’s nightmare or operator’s challenge?
    March 14, 2017
    Early - and continuous planning - is essential for successful road widening projects. By Nina Sacagiu, project manager, and Laurent Charles-Nicolas, project director, at Egis. Keeping goods and people moving safely is the primary objective of any transport authority across the world. Delivering this objective on motorways and making the most out of network capacity requires all the resources, skills and ingenuity of those in charge of managing the infrastructure. When the network can no longer cope wit
    Read More
  • The drive for US road funding: will corporate America get a seat?
    September 13, 2017
    Trumponomics aims to use public money for pump-priming an even greater amount of cash from the private sector to improve America’s crumbling roads. But is political will matching corporate America’s enthusiasm for more private investment, asks David Arminas If there were ever a test case for comparing public-private partnerships and design-build contracts, the recently completed Ohio River Bridges Project is it (see previous article).
    Read More
  • Upgrading a busy A road link in the UK
    July 4, 2018
    The upgrade to the UK’s busy A14 route will address a significant traffic bottleneck - Mike Woof writes The UK is suffering badly from traffic congestion, a problem that is particularly severe in and around its major cities. Lack of investment in road construction over many years has resulted in a major backlog of work, while the country has seen growing vehicle numbers. To make matters worse, there have been few additions to the major road network since the late 1980s and early 1990s. And the combinatio
    Read More

Highlighted Content