Initial Brief

The work being managed by Alstom, as part of the Bristol Area Signalling Renewals and Enhancements (BASRE) programme, involved 711 signalling equivalent units (SEUs), making it the largest recontrol and relock exercise ever undertaken in the country.

BASRE had three key drivers:

  • renewal of the asset due to its condition
  • the need to provide an Alternating Current (AC)-immune and electrification-gauge-compliant signalling system, ahead of the running of the first electric passenger train to Bristol in December 2016
  • to achieve capacity and journey time improvements on the Filton Bank as part of the Control Period 5 Infrastructure Improvement Programme

WCL were engaged to provide Project management and consultancy services for all the GRIP 5-8 stages of the works.


With large volumes of signalling work proceeding all over the country, as well as on the Western Route, signal engineering design resources were under significant pressure. We recognised the importance of effective programme management in responding to this risk, prioritising the effective and efficient deployment of resource throughout the delivery of works. 

WCL developed new ways of working and design development processes throughout the course of the project that allowed data design to proceed across multiple stages. We adopted specific gateways to maintain engineering assurance for the entire scheme.

Due to the sheer volume of outputs that had to be achieved in such a short space of time, WCL defined and divided works up into distinct project teams that were assigned specific stages. We undertook a high volume of interface management across all stages to ensure consistency and quality working practices throughout.


We provided instrumental support in helping Alstom project manage and deliver the design, build and successful commissioning of all major stages of this significant programme of works.

Key project outputs achieved with WCL were:

  • an immunised and re-gauged signalling system ready for electrification
  • a signalling system relocked and re-controlled under the ‘85% compliance approach’, which assumes existing signal positions remained largely unchanged
  • the re-control of the Bristol Power Signal Box area (excluding Bristol South) signalling to Thames Valley Signalling Centre, in line with the National Control Centre Strategy
  • modifications to signal structures to make signals safely maintainable under OLE
  • installation of the RSC in accordance with the Immunisation Strategy
  • installation of a fibre-optic cable in the troughing for the IPC related to the OLE Supervisory Control and Data Acquisition system
  • the four-tracking of Filton Bank (and associated signalling infrastructure) to facilitate capacity improvements between Dr Day’s Junction and Filton.