Project Overview

Old Oak Common Station is the future London interchange for High Speed 2 (HS2), supporting high-speed and conventional rail services, including Crossrail. Located on the existing Old Oak Common Railway Depot, the station will provide six sub-surface high-speed platforms and eight surface-level conventional platforms, with services planned to commence in 2030. Designed as a major transport gateway, the station will deliver efficient intermodal connections and a high-quality passenger experience, reflecting HS2’s Design Vision centred on People, Time and Place.

Technical Overview

The UTX works included the installation of eight 1.2m internal diameter precast concrete pipejacked bores beneath the GWML and IEP railway lines, passing under eight live tracks without disruption to rail operations. Bores were installed at depths of approximately 6.7m below rail level, using launch and reception pits formed with steel sheet piling and silent piling techniques to minimise environmental and operational impact.

The sewer diversion involved installing a 1,200mm diameter main sewer, reducing to 450mm, delivered across three phases. This included pipejacking beneath live railway lines and operational train depots, open-cut installation within Wormwood Scrubs Park, and construction of multiple new manholes. An 800m temporary access road through protected marshland was also delivered to facilitate the works.

Scope of Works

JGL delivered two major enabling works packages between 2021 and 2023 in support of the HS2 Old Oak Common Station development:

Construction of an Undertrack Crossing (UTX) beneath live railway infrastructure using large-diameter pipejacking techniques.
Diversion of the Thames Water Stamford Brook Sewer, including extensive enabling works, temporary access arrangements and multi-phase sewer installation across operational rail corridors and sensitive environmental areas.

Technical Complexity & Innovation

Installation of multiple parallel pipejacked bores beneath live rail infrastructure with zero impact on services.
Design and supply of a bespoke 1200mm HDPE flanged SDR17 pipe within the HS2 Station Box to accommodate predicted future structural movements.
Procurement of oversized HDPE pipework and flanges from Germany, exceeding UK manufacturing limits.
Development of custom movement joints, bespoke pipe supports within a reinforced concrete trough, and an integrated low-flow channel to ensure long-term system performance.