HS2 outlines timeline for London construction works

The high-speed railway, HS2 recently published a high-level report into its construction plans for the next few years. The timeline covers most of the concrete phase of the project before handing over to signalling and mechanical/electrical fit-out.

Phase One of HS2 – from London to Birmingham is planned to open between 2029 and 2033, and comprises 140 miles of high-speed rail, four high-speed stations, two major depots, 10 tunnel boring machines, 32 miles of tunnels, over 50 viaducts, 110 embankments, 71 cuttings, over 150 bridges and over 100 construction sites.

Euston Approaches test piling works (c) HS2

The timeline for London HS2 works 2020-2023

Sept 2020

First tunnel boring machine (TBM) delivered to the Chiltern tunnel portal in North-West London.

Dec 2020

Commence cavern constructions in North London – to allow trains to cross over tracks when necessary.

Main construction starts for both the Euston and Old Oak Common stations

Autumn 2020

Construction of piles and ground anchors for the railway’s approach to the new station. The piles being installed in the Euston approaches will be up to 50m deep and 1.8m across to support the station and stabilise the ground.

“Late” 2020

Building blocks for the Colne Valley viaduct will start coming into place, with the trestles being laid. Main construction of the viaduct will begin in 2021, started at the southern end. From July 2022, the decking will be laid on top of the pillars, with construction largely completed in 2024.

Jan 2021

Subject to Phase 2a Royal Assent grant — the West Midlands to Crewe section – contracts will be placed for all 10 tunnel boring machines

April 2021

Start tunnelling the Chiltern tunnel – when complete it will be the 5th longest tunnel in the UK.

It will take three years of operation to construct each tunnel. The upline tunnel, through which trains will head to Euston – will begin first. The launch of the TBM for the downline tunnel (for Birmingham-bound trains) will happen approximately two months later.

In addition, 5 ventilation shafts will be dug down along the tunnel route.

June 2022

Start tunnelling the Northolt tunnel – a 13.4 km long twin tunnel to Old Oak Common.

Constructing the tunnel will be the work of four tunnel boring machines. Two TBMs will set off from the tunnel portal at West Ruislip, driving east towards the Green Park Way shaft to complete the western section of the tunnel. Two more will work from the west of the Old Oak Common site, heading towards the Green Park Way shaft to build the eastern Northolt section.

July 2022

Colne Valley viaduct decking construction starts (see April 2021)

Dec 2023

Start tunnelling the 7.2 km long twin-bore tunnels from Old Oak Common towards Euston station.