PRESS RELEASE

Lower Thames Crossing construction traffic delays could top £1bn

Transport Action Network (TAN) [1] has calculated that the cost of the delays caused by constructing the Lower Thames ‘smart’ motorway Crossing (LTC) [2] could be well over £1bn, based on the disruption caused by the controversial M25 Junction 10 scheme in Surrey. The LTC will have a 7-year construction period, twice that of the M25 scheme.

National Highways estimated (when seeking planning approval) that the cost of time delays due to the construction of the LTC would be £200m. Yet there is no guarantee that this is accurate. With the construction of the M25 J10 Wisley interchange, when seeking planning approval, National Highways estimated time delays would cost £11m. Yet once permission was granted, that jumped up to £45m. However, Highways Magazine calculated the true cost was likely nearer £100m [3]. That was without including direct costs to businesses. For example, the Royal Horticultural Society estimates that the disruption will have lost them around £11m [4].

Applying a similar jump in construction delay costs to the Lower Thames Crossing, would result in costs of nearly £2bn. Given the proximity to London Gateway and Tilbury Port and the likely disruption it will cause them, the direct costs to these businesses could be significant. The LTC also connects to the M25 at Junction 29, and will cause significant disruption at this vital point above the Dartford Crossing.

Chris Todd Director of TAN, said:

“The Lower Thames Crossing makes no sense on so many levels and this is just another example where there has not been sufficient scrutiny of National Highways’ proposals. The M25 J10 debacle shows National Highways estimates are unreliable with construction disruption massively underestimated. The cost of delays caused by the biggest road building project in a generation could be well over £1 billion.

“The government has stated its intent on fuelling economic growth, but through its approval of the LTC, risks getting motorists stuck in 7 year long traffic jams. This will cost businesses dear.

“That’s why we believe the government should be investing in public transport based alternatives instead – as proposed in our Essex-Kent Superlinks report [5]. The government needs to be making things better, not worse.”

– ENDS –

Notes to editors:

[1] TAN was set up five years’ ago by director, Chris Todd, to help communities press for better (more sustainable) transport. We support more investment in bus and rail services and active travel. To enable this and better roads maintenance (fewer potholes) we continue to oppose the previous government’s damaging roads programme. We also support better integration between transport and planning.

[2] Planning consent for the Lower Thames ‘smart’ motorway Crossing was approved by the Secretary of State for Transport on 25 March, 2025.

[3] See TAN’s latest blog on its National Highways Watch page: True cost of traffic delays from building major roads

[4] Royal Horticultural Society press release, 17 January, 2025

[5] Essex-Kent Superlinks report, February 2025. More information about TAN’s concerns about the Lower Thames Crossing is detailed here.