Two years into the largest transportation infrastructure project in Virginia history, crews recently begun pouring what will be the surface of the new bridge for the Hampton Roads Bridge-Tunnel expansion. But much of the progress being made on the $3.8 billion project is happening underground.
The expansion, aimed at reducing congestion along one of the region’s busiest roadways, is still on schedule to be completed in November 2025, according to Rob Gianna, project manager for Hampton Roads Connector Partners. That’s despite early delays associated with the pandemic-induced supply chain issues.
The project involves widening Interstate 64 from two lanes in either direction to four, and adding two two-lane tunnels next to the existing tunnel, effectively doubling the capacity of this stretch of highway. During peak traffic hours, congestion can reach more than 6 miles along I-64, according to the Virginia Department of Transportation.
The new bridge will be situated about 13 feet higher than the current one at the highest point, and curve out further east. The curve will be tilted in order to maintain the 55 mph speed limit while connecting back to the same point on land and the current bridge, Gianna said Thursday during a boat tour of the project site for local news outlets. The added height will also serve to reduce maintenance needs associated with more severe weather conditions caused by climate change, he added.
Between 175 to 200 crew members are working on the bridge construction on a given day, and between 600 and 750 total are involved on the entire project, including subcontractors, Gianna said. So far, they’ve installed 500 of the necessary 1,200 pilings that will support the new structure.
The heaviest workload, however, is being done by Mary, the $101 million tunnel boring machine tasked with digging the two new tunnels, which will be 50 feet deeper into the Chesapeake Bay’s floor than the existing tunnel.
Mary is designed to the specifications of boring through the type of sediment found in the Elizabeth River — a sandy, peat moss type of sediment that is very unstable, said Brooke Grow, a spokesperson for the HRBT project. Therefore Mary can’t be reused in a project in another region, even one as close by as the Chesapeake Bay Bridge Tunnel.
Once Mary’s job is done, it will be stripped for parts, according to Grow.
The contractors chose to bore the new tunnel, rather than install it by lowering the prebuilt tube into a trench as the existing tunnels were, in order to avoid disrupting the wildlife and to ensure that the Navy and other major marine vessels are not impeded during construction, Grow said.
As construction progresses with the project, planners are aiming to limit traffic disruptions to weekends and nights, at least in the early stages of construction. The first “dramatic” traffic disruptions will begin around January and February 2023, barring any significant delays. Grow said public announcements will alert commuters of any upcoming changes before they are made.
The current Hampton Roads Bridge-Tunnel structure will turn 65 years old on Nov. 1, and still has another 35 years of use in it, with continued maintenance. The new structure, built with carbon fiber and reinforced steel, among other improvements, will have a life span of 100 years and won’t require as much maintenance costs, according to Gianna.
Grow explained that Hampton Roads has seen a great deal of growth since the current bridge-tunnel was built, and this project is an effort to meet those demands and prepare the region for the future. A less-congested I-64 will also mean a more efficient means of egress in the event of a natural disaster such as a hurricane.
“I think this structure not only improves travel time reliability, it also makes it a lot safer as well,” Grow said.
When complete, the current tunnels will serve all westbound traffic, and the new tunnels will serve all eastbound traffic, Grow said. There will be two general purpose lanes in each direction, one drivable shoulder in each direction, and two high-occupancy vehicle tolled lanes in each direction.
“Toll prices have not been discussed at this point in the project,” Grow said in an email.
It’s unclear if the existing bridge-tunnel will be decommissioned at any point.
The Hampton Roads Bridge-Tunnel Expansion Project is part of the Hampton Roads Transportation Planning Organization’s 2045 Long-Range Transportation Plan.
source pilotonline