The 1.4 km (0.87 miles) twin-bore tunnel runs between west Silvertown, east of the River Lea estuary, on the north side of the Thames and a portal adjacent to the existing Blackwall Tunnel on the Greenwich Peninsula south of the river.

Promoted by Transport for London, the tunnel is being delivered through a design, build, finance and maintain contract by the Riverlinx consortium which was awarded in November 2019.

[6][7] Since 1999, major public transport improvements in east London have added cross-river connections, including the Jubilee Line Extension, extensions of the Docklands Light Railway to Lewisham and Woolwich Arsenal and the opening of the Crossrail Project as the Elizabeth line.

[9] Mayor Livingstone expressed a preference that the link be a road tunnel, and that construction would follow the implementation of the Thames Gateway Bridge.

[12] A public consultation on the Silvertown Tunnel and the Gallions Reach Ferry took place between February and March 2012.

[15] Following a Nationally Significant Infrastructure Project inquiry,[16] the government approved the proposal in May 2018,[17] and the contract was awarded in November 2019 to the Riverlinx consortium.

[30] Taxis, blue badge holders, wheelchair-accessible and 'zero-emission capable' private hire vehicles licensed by TfL will be exempt.

Discounts are available to low income drivers in 12 boroughs, and for small businesses in Tower Hamlets, Newham and Greenwich.

[32] Route X239 will run an express section between Blackheath (Sun in the Sands) and Blackwall (Leamouth) via the tunnel.

Green Party member and councillor Caroline Russell expressed concern that as the cost of the tunnel would be covered by tolling, future mayors of London will want to keep traffic levels high in order to pay this off.

However, revised plans submitted in 2021 suggested over 100 trees would be removed to construct the tunnel and access roads.

The report was published by Transport Action Network, Stop the Silvertown Tunnel coalition, Speak Out Woolwich and Extinction Rebellion Greenwich.

[60] In July 2020, Extinction Rebellion protesters locked themselves to a drilling rig, calling on Mayor of London Sadiq Khan to halt the project amidst environmental concerns.

[61] In April 2021, 52 academics and campaigners sent a joint open letter to transport secretary Grant Shapps and Mayor of London Sadiq Khan seeking an "emergency review" of the proposed tunnel's environmental impact.