Transport for London names preferred Silvertown Tunnel bidder30 May 2019
Great Britain – The Riverlinx consortium is set to build the Silvertown Tunnel. The group comprises Aberdeen Standard Investments, BAM PPP PGGM, Cintra, Macquarie Capital and SK Engineering & Construction.
Throughout the Summer, the consortium will work to confirm financial arrangements with lenders in respect to the project and set up the supply chain. Only once these are all agreed will Transport for London (TfL) award them the contract for the project.
The new road tunnel will provide a new Thames crossing in east London, connecting Greenwich Peninsula and the Royal Docks. It will relieve pressure on the notoriously poor Blackwall Tunnel, which was closed over 700 times in 2017/18 and is considered the least reliable crossing of the river. The result is constant congestion.
Atkins produced the reference design, which sees a twin-bore tunnel of two 11.45m ID bores, each 1km in length and featuring connecting cross passages. Cut-and-cover approaches at each end will measure 0.2km in length, with a TBM chamber at the interface with the bored tunnel.
A spokesperson for Atkins said, “The major challenge for the project with regards to design and construction is the fact that it would be built in the area that historically was highly developed by a heavy industry, and underground remnants of redundant and demolished structures are still are present. Additionally, in recent years, new infrastructure such as Docklands Light Railway (DLR), Woolwich Branch Viaduct, and Emirates Air Line (EAL) were constructed in the close proximity to the proposed tunnel route. Therefore, when developing the alignment, it was of high priority that the following requirements would be met.”
The project is to be constructed under a GBP 1bn Design, Build, Finance and Maintain contract. A spokesperson for TfL added, “Payments by TfL [will start] only once the tunnel is open and available for use. TfL will also be able to reduce payments should the tunnel not meet certain key standards, such as availability for use by traffic and physical condition. Over the last 20 years TfL has developed significant experience in how to manage similar contracts, which have successfully helped deliver extensions to the Docklands Light Railway. Funding the project this way not only shifts financial risks onto the private sector, but also incentivises them to deliver the scheme as efficiently as possible.”