Washington Bypass Bridge
- Mar 6, 2012
U.S. Highway 17 Washington Bypass Bridge Design-Build Project
Construction of a new four lane Washington Bypass bridge started in February 2007. The 6.8 mile project includes four bridges, two major interchanges and will relieve congestion on US 17. The project required a major crossing of the Tar River and adjoining environmentally sensitive wetlands. More than 80% of the bridge (2.3 miles) is on tangent horizontal alignment with a continuous 70-ft. deck width. A vertical clearance of 45 ft. is provided over the Tar River navigational channel.
AECOM was the lead designer for the joint venture of Flatiron Constructors and United Contractors (Flatiron-United) team, which developed a top down construction approach to minimize impact to the environmentally sensitive and accelerated construction schedule. It was the world's first application of the pile-driving operations from an erection gantry, which not only saved time and cost, but also eliminated the need for large cranes and temporary access trestles, significantly reducing environmental disturbances to more than 14 acres of the fragile wetlands below.
The new bypass was completed eight months early and begins north of town, forking west from existing US 17. It curves south and crosses US 264 (a major east-west route carrying traffic to and from Raleigh) and the river. It curves east and crosses back over mainline US 17, and then under NC 33.
The project included construction of a three-mile bridge over the Pamlico-Tar River and environmentally sensitive wetlands.
At the time of bid, the $192 million project was the largest construction contract ever awarded by NCDOT.