Civil Engineering News | <Full Story>
Washington, D.C. — Skanska, leading a joint venture of Skanska, Kiewit Construction and Weeks Marine (SKW Constructors), reached substantial completion of the new Midtown Tunnel, a key element of the Elizabeth River Tunnels (ERT) project between Norfolk and Portsmouth, Va., four months ahead of schedule.
“This project was Skanska’s first public private partnership (P3) in the U.S. and the early completion clearly demonstrates the value that Skanska can provide in developing and investing in critical infrastructure,” said Johan Henriksson executive vice president, Skanska Infrastructure Development. “P3 allows for effective risk recognition and mitigation and more efficient and accelerated procurement than the traditional design-bid-build process.”
The ERT project consists of Elizabeth River Crossings (ERC), a joint venture of Skanska Infrastructure Development and Macquarie Infrastructure and Real Assets. The project is using a P3 model for the finance, development, design, construction, operation and maintenance of a new two-lane tunnel adjacent to the existing Midtown Tunnel under the Elizabeth River, connecting the communities of Norfolk and Portsmouth. The 3,800-foot-long underwater vehicle tunnel is one of the few immersed-tube tunnels in the U.S., and is comprised of eleven, 16,000-ton concrete elements.
The tubes were fabricated at Sparrows Point, Md., and towed 220 nautical miles down the Chesapeake Bay to the project site in Portsmouth. They were then immersed and positioned — one element at a time — in a dredged trench nearly 100 feet at the bottom of the Elizabeth River and then connected together through a series of locking mechanisms and seals.
“It is a significant accomplishment to have completed the new Midtown Tunnel several months ahead of schedule,” said Wade Watson, ERT Project Director for SKW, responsible for the design-build aspect of the project. “This allows us to begin rehabilitation of the existing Midtown Tunnel months sooner than originally planned.”
The new tunnel will reduce traffic congestion on U.S. 58 by providing extra travel lanes, and enhance driver safety by having one tube for eastbound traffic and another tube for westbound traffic. The existing Midtown Tunnel is more than 50 years old. It is considered the “most heavily traveled two-lane road east of the Mississippi,” according to the Virginia Department of Transportation. When it first opened, it handled nearly 8,400 vehicles a day. In 2013, that number rose to nearly 40,000 per day. Traffic is projected to rise to nearly 50,000 vehicles per day by 2026.
“Opening the second travel lane in the US 58 West Midtown Tunnel immediately doubles roadway capacity for motorists traveling from Norfolk to Portsmouth,” said ERC CEO Greg Woodsmall. “Our project team worked extremely hard to deliver this much-needed improvement, months in advance of our contract delivery date. This new facility will help to reduce our regional congestion, ultimately improving the quality of life for Hampton Roads residents.”
Now that the new Midtown Tunnel is operational, the existing Midtown Tunnel will undergo rehabilitation to bring it up to the same standard and the Martin Luther King Expressway will be extended from London Boulevard to Interstate 264. Maintenance and safety improvements to the existing Downtown Tunnels (both eastbound and westbound tubes) has already reached substantial completion.