ARNOS GROVE TFL SIDINGS

DPH acted as Principal Contractor for the delivery of the Arnos Grove DNO cubicle installation for Transport for London, providing a fully coordinated civil and electrical package to establish new incoming services to the TDS building. The works required controlled delivery from initial investigation through to final terminations, with careful planning to maintain safety, quality and compliance within an operational LU environment.

 DPH’s scope commenced with initial surveys and investigations, followed by devegetation, spoil clearance and ground preparation to enable construction activities. The team completed the required excavation works for the new DNO base, turning chamber and trenched service routes, including the installation of the turning pit and new ducting between the DNO cubicle and the TDS building. DPH then installed formwork and poured concrete to form the new foundations, before completing full reinstatement of surfaces around the base, turning chamber and infill trench. All excavated materials and general waste were managed through licensed removal and disposal, maintaining a clean, compliant working environment throughout.

 Following completion of the civils works, DPH managed the delivery, positioning and bolt-down of the new DNO cubicle, then pulled in the TDS supply cable through the new duct route and completed terminations at both ends. The package included the installation of new tails within the DNO cubicle, earthing installations including dedicated earth electrode works, and the provision of new core holes through both external and internal walls to accommodate services and containment interfaces. Internally, DPH installed new cable tray and bracketry between the TDS building and the comms room, supporting a clean and maintainable route for associated services. To ensure compliant sealed penetrations at building entry points, DPH also supplied and installed two Roxtec frames at high level on the TDS building.

The programme was completed with out-of-hours working in operational rooms and areas within Ash House, enabling progress while protecting day-to-day operations. The completed installation provides a robust, maintainable incoming supply arrangement to the TDS building, delivered under DPH’s controlled delivery approach and aligned with the standards expected on London Underground infrastructure.