STIP: Upper Holloway – Rail
HOCHTIEF is replacing four road-over-rail bridges in central London as part of TfL’s Structures and Tunnels Investment Portfolio (STIP). We successfully demolished and rebuilt the Holloway Road Bridge, which carries the busy A1 over the London Overground at Upper Holloway Station, phasing the works carefully to limit disruption to the London road and rail networks.
- Road-over-rail bridge deck demolition and construction
- Abutment strengthening
- Service bridge
- Complex utilities diversions
- Traffic management
As the bridge is located above rail lines and next to Upper Holloway station, we could only complete permanent works in short time periods during public holidays. We developed our programme around available rail possessions and planned to complete the works during Network Rail’s scheduled installation of overhead line electrification to minimise disruption to rail passengers. We also worked with the designer to optimise the bridge design to maximise offsite prefabrication. This increased quality and safety while reducing time on site to ensure that we could complete the main works within the allocated possession.
As much of the enabling works for the bridge took place inside Upper Holloway Station, it was decided to close the station entirely for three months prior to the main Christmas blockade. This reduced the risk to the possession and the impact on stakeholders. We worked with both TfL and Network Rail to develop mitigation measures, including passenger access routes through the site, to minimise inconvenience to travellers. We successfully demolished and replaced the bridge during a scheduled four-day Christmas blockade of the overground railway. We achieved 20,000 injury-free man hours during the works and completed the bridge on time.