Portal Buildings, Silvertown Tunnel

A Nationally Significant Infrastructure Project, it involves unique planning processes. The project was tendered by Transport for London (TfL) through PFI with a Development Consent Order, which effectively granted the project outline planning permission prior to the tender process. Underpinning this was a number of design principles and technical requirements for the scheme drawn up by TfL, providing parameters within which the Riverlinx consortium design team has worked.

Each of the portal buildings has its own technical requirements. The northern Newham portal services building acts as the main service and workspace for the tunnel operators. The southern portal at Greenwich operates as a secondary back-up facility. dRMM have developed a shared visual language and material palette across the two sites, with the detailed design of each portal responding to the individual building use and context. The designs minimise the need for foundations, using the tunnel structure to provide support.

The buildings are recognisable as the threshold to a significant piece of infrastructure, acting as markers for Silvertown and Greenwich, places in progress which will continue to change over the centuries these structures are in use. Green roofs planted with the same species found in the wider landscape scheme help connect the buildings with their surroundings.

The services building houses the essential tunnel maintenance and operation equipment, placed next to the road. The main building has a conical form placed on a green landscaped plinth above the tunnel entrance. The building can deliberately see, and be seen, from all angles – a lookout point. The circular form offers excellent efficiency and views for all staff. The upper floors house work spaces and tunnel management facilities. The ground floor has main entrance, circulation and wellbeing facilities.

The design geometry uses curvature to work with the landscape and provide some sculptural subtlety to this major piece of infrastructure. This building provides operational continuity in the event of any issues with the Newham portal, with administrative offices for tunnel management and plant rooms with mechanical and electrical systems equipment for the operation of the tunnel.

When completed in 2025, the tunnel will enable better transportation of goods across London and allow for improved public transport links, including more cross-river bus journeys.