The southbound Blackwall Tunnel will be closed again between October 21-23 as work continues on building the £2bn Silvertown Tunnel next to it.

A new flyover carrying traffic over the Silvertown Tunnel entrance came into operation on Monday morning, with drivers leaving the southbound Blackwall Tunnel veering left to use the new section of road.

Now the old road will be dug up and the short approach road to the new tunnel built in its place. Both tunnels will be tolled when the Silvertown Tunnel opens in 2025.

For work to start, the point where the A102 goes down from three lanes to two – an infamous cause of congestion – will have to be moved further south. TfL will be closing the southbound tunnel between 0001 on Saturday October 21 and 0500 on Monday October 23 for the work to take place.

Drivers are being asked to plan their routes in advance, while bus route 108 will run in two sections again, Stratford to Canning Town and North Greenwich to Lewisham, with passengers given free Jubilee Line travel between the two sections.

Traffic will enter the new tunnel in the space formerly occupied by the Blackwall Tunnel exit road. Image: Atkins/TfL 2015 visualisation

Previous closures have led to congestion across parts of southeast London, with queues on the A2 through Deptford, New Cross and the Old Kent Road. 

But drivers seeking to switch to public transport may find their options limited – other key north-south links to southeast London will also be closed that weekend, with Thameslink services through the capital not running on the Saturday or Sunday and the Docklands Light Railway between Stratford International and Woolwich Arsenal closed on the Sunday. 

In addition, there will be no trains at all on the Greenwich and Woolwich rail line on the Sunday. 

Carl Eddleston, the director of network management and resilience at TfL, said: “The Blackwall Tunnel is used by tens of thousands of vehicles every day and we appreciate that these works will have an impact on some drivers. 

“Having completed works to the southbound carriageway, we are now working to prepare the northbound carriageway for the new Silvertown Tunnel. 

“We have worked hard to try and limit the potential disruption these will cause, such as ensuring a northbound route can be maintained throughout these closures. We will also be taking the opportunity to carry out works within and around the tunnel to help deliver future maintenance work more efficiently and ensure it continues to safely operate.”