HS2 completes tunnel portal
Work to build the 3.5-mile Bromford Tunnel bringing high speed trains into Birmingham has taken a leap forward as excavation of the 22-metre deep west portal has been completed.
The portal at Washwood Heath has been finished in readiness for the two 1,600-tonne tunnel boring machines building the twin-bore tunnel to complete their journeys from Water Orton in North Warwickshire.
The huge earthworks operation has taken a team of 130 people from HS2’s construction partner Balfour Beatty VINCI nine months to complete.
Groundwork specialists from Coventry-based Duo Group supported BBV with the complex excavation programme to extract 53,400 sq metres of earth from the ground. The spoil has been transported on specially built haul roads to support construction of the Delta Junction – a triangular section of 13 viaducts in North Warwickshire.
The Washwood Heath portal is the deepest of four tunnel portals on the Midlands section of the HS2 route.
A two-year programme of ground reinforcement works, delivered by the Bachy Soletanche and Balfour Beatty Ground Engineering joint venture, began in November 2021 to prepare for the portal’s excavation.
The portal is at the start of a 750-metre-long cut and cover structure and is where HS2 trains will emerge from the tunnel and travel below ground level, before raising up onto a series of viaducts into Birmingham’s Curzon Street Station.
‘Mary Ann’, the first TBM to launch from Water Orton in 2023, is expected to break through the portal wall at Washwood Heath by the end of 2024, with the second TBM ‘Elizabeth’ set to finish her drive by the auutumn of 2025.
At 65 hectares – the equivalent of 100 football pitches – Washwood Heath is one of HS2’s largest construction sites. Next to the tunnel portal, HS2’s Depot and network integrated control centre will also be built.
From this site, trains will be serviced and stored and the real time operation of the railway will be controlled.
Alvin Pedzai, HS2 project manager responsible for main works civils delivery at Washwood Heath, said: “With two tunnel boring machines in the ground and excavation of the Birmingham tunnel portal complete, the complex feat of engineering required to bring HS2 trains into central Birmingham is well and truly underway.
“Local businesses have played a huge role in this two-year programme of work, which has been taking shape alongside our plans to build the new network control centre and maintenance depot - the beating heart of HS2’s operation here in Washwood Heath.”
