USA - Milestone in the construction of the HRBT extension project

22/04/2024

On 17th April 2024 TBM Mary broke through the headwall on the North Island at Hampton, completing the first of the two road tunnels for the USD 4bn HRBT expansion project in Virginia. The tunnel - 2.4km long and 14 m in diameter – extends 52.73 m under water’s surface in its deepest point. The TBM - launched from the South Island on the Norfolk side in April 2023 - installed 1200 concrete rings. In the next 6 months the TBM will be partially disassembled and then placed on a turntable section by section to be turned around and start boring the 2nd tunnel.

For further information on the project click here and us/125 for the tunnelbuilder archive and visit www.hrbtexpansion.org. 16/24.