Silvertown Tunnel cost pressures emerge as opening date pushed back  

TfL’s direct capital costs are currently estimated to run £12M over budget. The opening date for the East London road tunnel has also been pushed back by a month, according to meeting agenda papers released ahead of TfL’s next Programmes and Investment Committee meeting.

So far, TfL has spent £73M with £112M more forecast to be spent. However, the agenda papers add that there remain “significant risks” which could “have a significant impact” on the final cost of the project.

Construction costs are being incurred by the Riverlinx consortium which has a design, build, maintain and finance contract. The joint venture is formed of Bam Nuttall, Ferrovial Construction and SK Ecoplant and has the contract to design, build and maintain the tunnel. Industry estimates put the cost at up to £2bn over the 30 year contract.

The meeting agenda papers add: “The EFC [estimated final cost] is currently £12M over the delegated programme and project authority of £173M, owing to inflation increases and the agreed Safe Stop during the first lockdown during the coronavirus pandemic.

“The main change in EFC since the last report is owing to further inflationary pressure, particularly around land purchases and resource.”

The minutes add that there are still “significant risks around land compensation and ground conditions” and “if these were to materialise, it may have a significant impact on the EFC”.

The papers add that “ongoing shortages of skilled labour and supply of construction materials” has led to a 20-day delay in the project’s predicted opening date.

The tunnel is now scheduled to open in May 2025, rather than mid April.

The 1.4km twin bored Silvertown Tunnel will connect south London with the Tidal Basin Roundabout in Silvertown, in a bid to relieve congestion at the Blackwall Tunnel.

The drive on the new road tunnel has now reached 280m and the TBM is expected to have completed its journey under the river by Christmas.

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