Driving down the cost of transport infrastructure in London

London could deliver major transport infrastructure projects between 20 – 50 per cent cheaper if it followed processes in place in other major European countries, according to a London Assembly Budget and Performance Committee report.

The extension of the metro system in Madrid, Spain, between 1995 and 1999,¹ was notable for a low-cost and speedy approach, with a 35-mile extension of the network costing the equivalent of US$2.8 billion (£2.1 billion) in 2024 prices.

However, the extension of the London Underground Jubilee line cost ten times as much per mile.

The Committee has today published its report – Mind the Funding Gap - calling for Transport for London (TfL) to review the delivery of its largest transport infrastructure projects since 2015 against a checklist to produce an infrastructure cost audit, aiming to identify what recurring issues have affected London’s transport infrastructure projects recently, and what potential options there are to reduce costs.

TfL has an ongoing capital programme and has delivered major projects in recent years such as the Elizabeth line, Northern line extension and Silvertown Tunnel. Other key schemes, including the Four Lines Modernisation programme for the Tube, are ongoing.

However, other proposed upgrades including Crossrail 2, the Docklands Light Railway (DLR) extension – which has recently been backed by government in the 2025 Autumn budget - and repair of Hammersmith Bridge have languished for years without the funding required deliver them.

The proposed DLR extension from Gallions Reach to a new station at Beckton Riverside, and then under the river to Thamesmead, is expected to cost £1.7 billion.² In the government's Autumn Budget, it announced that "the majority of the costs will be met by TfL and GLA, with the government also contributing over the long term." It will also work with the GLA for options of "innovative financing to support the delivery of infrastructure projects in the capital."³

Based on the evidence heard during the investigation and other studies, the Committee has produced the following checklist to be considered by TfL when it plans and develops new infrastructure projects:

• Reducing the length of development periods
• Avoiding ‘stop-start’ delivery
• Phasing of delivery where appropriate, rather than delivering ‘all in one go’
• Reducing the length of project delivery periods, which can reduce risk
• Avoiding over-scoping of projects
• Reducing the length of environmental impact reviews
• Addressing the complexity of the supply chain
• Improving the capacity of planning officers
• Developing a strategic view

Other recommendations in the report include:

• The Mayor and TfL should restart the promotion and development work of the Crossrail 2 project with a particular focus on how delivery costs can be minimised and how the project will be financed.
• The Department for Transport, the Mayor and TfL should produce and publish a strategy for funding new infrastructure via private investment. This should include a standard model for the long term that allows Tax Increment Finance from new revenue streams to be enabled from new transport infrastructure.

Chairman of the London Assembly Budget and Performance Committee, Neil Garratt AM, said:

“Delivering new transport infrastructure has wide-reaching benefits for London, Londoners, and the wider country, yet challenges remain with funding and spiralling development costs.

“We have seen some highly successful schemes delivered in recent years, but have now seen a number of schemes stall for varying reasons.

“Through our investigation, we sought to understand how major cities in other countries are delivering large scale transport infrastructure projects, at a fraction of the cost we seem to face here in London.

“We heard evidence that shows London could deliver major infrastructure projects between 20 and 50 per cent cheaper if we adopted some of the planning and financing processes in neighbouring countries.

“Ensuring London has a pipeline of infrastructure improvements highlights London’s appeal as a place for people to live, work and invest, and we all want to see our city thrive.

“We are urging the Mayor to implement our cross-party recommendations, which could help London deliver the transport network the city wants and needs.”