The Black Narrows Bridge and the Chincoteague Channel Bridge on Route 175 provide the only access to Chincoteague Island, Va.
In recent years, the bridges began falling into ill repair, prompting the town to call upon the Virginia Department of Transportation (VDOT) and the Commonwealth Transportation Board (CTB) to supply funds to replace the bridges.
The town of Chincoteague, famous for its annual Pony Swim and Auction, cited the roughly 4,000 residents and more than 1 million tourists each year who use the bridges as the primary motivation to approve the $68.7 million project. In January 2007, American Bridge Company, Richmond office, was awarded the contract, and work began that March. The scheduled completion date is November 2009.
The replacement project calls for the construction of two new bridges that intersect one another over Black Narrows, Chincoteague and Lewis Creek navigational channels. A new 0.75-mi. (1.2 km) bridge will be built over Black Narrows and Lewis Creek Channel, and a 729-ft. (222 m) connector bridge will be built linking the new bridge to Marsh Island. There will be a single lane of traffic in each direction, divided by a double line. What’s more, the lanes will be wider than the old bridges’ in order to meet current standards.
The primary bridge will begin on the west side of Black Narrows at Route 175 and span north to connect with Maddox Boulevard in town at the Main Street intersection. A bascule bridge will be installed as part of the new span that crosses over Lewis Creek Channel.
This new primary bridge will allow motorists to access Marsh Island via a second bridge called the Marsh Island Connector. The Marsh Island Connector will exit onto Marsh Island at the same location as the soon to be demolished Black Narrows Bridge. The Chincoteague Channel Bridge also will be demolished following construction.
At this time, American Bridge has completed the concrete bridge test pile phase, and crews are now driving production piles. Furthermore, the contractor is driving 48-in. (122 cm) piles at the bascule pier and placing pier caps on some of the piles. American Bridge brought in its Manitowoc M250 barge-mounted crane to drive 36-in. (91 cm) piles below the mud line, among other tasks.
American Bridge has Kevin Moynihan, project manager, and Tom Dey, assistant project manager, working on the job site. According to Dey, the Manitowoc M250 has a Bruce hydraulic pile hammer attachment that is used for work on the 14-in. (36 cm) steel pipe piles at the abutments.
“It is the second largest hydraulic hammer in the United States,” said Dey.
In addition, American Bridge is using another Manitowoc, a 4100, which is on a flexifloat. The company is also making use of a Tadano rubber-tire 60-ton (54 t) capacity crane.
Temporary bridges, or trestles, had to be built prior to constructing the new bridges, so American Bridge brought in two barge-mounted crawler cranes that remain on-site. An American 9320 crane is still being used, and an American 9299 crane is now located at abutment A.
Additional work that has been finished includes the completion of the concrete retaining wall along the Black Narrows marsh land. Six massive transmission line poles have been installed in preparation of the power company relocating power lines. Concrete pours will begin in March, which includes pouring the foundation for the moveable span pier and pouring the pier cap beams.
This project comes with environmental protection restrictions because the Colonial-nesting bird chooses to mate and nest in the waters surrounding Chincoteague Island. Tia Freeman, VDOT’s public relations specialist, said that the “environmental protection restrictions were lifted in the Fall and are coming back April 1 through Sept. 1.”
When asked if work has to stop entirely on the project due to the environmental concerns, Dey said, “No. We just move from one area to another and away from the marsh.”
During the restricted period, no work can be performed at what Freeman calls “the transition zone between the existing causeway and the new bridge.” Still, there are plenty of other tasks that can be performed until September. Even so, VDOT and the contractor constantly monitor construction activities to ensure compliance with environmental regulations.
The numerous benefits resulting from the new bridges will be worth the wait for the townspeople and the many yearly visitors. Traffic congestion in downtown Chincoteague will be reduced, boaters will have better channel access and the number of necessary bridge openings will be reduced. In addition, the wider lanes and shoulders will enhance motorists’ safety and industrial access may improve because VDOT will be able to consider permits for overweight loads. CEG