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The 拢2.2bn Silvertown tunnel has opened today, marking the completion of London鈥檚 first new road tunnel beneath the Thames in 45 years.

Built by Riverlinx CJV, a joint venture between Ferrovial, Bam and SK ecoplant, the pair of tunnels run for 1.4km between Newham and North Greenwich and is one of the UK鈥檚 widest road tunnels.

It aims to reduce chronic congestion on the adjacent Blackwall Tunnel, which currently closes more than 700 times a year, creating long tailbacks.

Other firms working on the scheme include architect dRMM, which designed the two portal buildings at either end of the tunnel which will be used for services and incident response.

First announced in 2012, the scheme was awarded through a public-private partnership to a consortium of developers consisting of abrdn, Invesis, SK ecoplant and Ferrovial鈥檚 highways division by Transport for London in 2019.

Construction by Riverlinx CJV on a 拢1.2bn contract started in 2021 with tunnelling, using the UK鈥檚 largest tunnel boring machine (TBM), getting underway the following year.

The TBM, which had a diameter of 11.9 meters and was 82 metres in length, started in Newham and averaged 22 metres a day before being turned around in a specially built rotation chamber at Greenwich using nitrogen 鈥渟kates鈥�.

It then completed the second tunnel by feeding back spoil through the conveyor belt system which had been installed within the first tunnel.

Nearly 1.9 million tonnes of excavated material was transported to and from the site by river barge, with all bored spoil transported to a former landfill site in Essex as part of a restoration scheme.

Once tunneling was completed, seven cross-passages were built connecting the two tunnels, four of them using a ground freezing technique.

The last major road tunnel beneath the Thames to open was the east tunnel at Dartford Crossing in 1980. 

There are now four road tunnels east of Tower Bridge, the Silvertown Tunnel, the Rotherhithe Tunnel, the Blackwall TUnnel and Dartford Crossing.