Mayor Jason Perry has written to the Minister for Growth, Dan Tomlinson MP, calling for government action to tackle the Croydon rail bottleneck and unlock billions of pounds of economic growth.
The Mayor is asking the Cabinet Office to bring together ministers, Network Rail, Gatwick Airport and councils along the Thameslink corridor to agree a way forward. His letter follows an approach to Transport Secretary Heidi Alexander in August, requesting a fresh assessment of the investment needed.
The constrained tracks and junctions around East Croydon and Windmill Bridge limit capacity and spread delays across the network. For Croydon residents, that means less reliable journeys to work, missed connections and disruption to everyday travel.
With Gatwick’s £2.2 billion Northern Runway project expected to support around 14,000 jobs and contribute approximately £1 billion a year to the regional economy, the Mayor argues that addressing those constraints has become increasingly urgent.
Every regular rail service between London and Gatwick passes through East Croydon. The airport’s expansion depends on more passengers using public transport, putting additional pressure on a route already recognised as one of the country’s most significant railway bottlenecks.
In his letter, Mayor Perry said:
“It would make little sense for the country to approve a £2.2 billion airport investment, with major regional and national economic benefits, without properly assessing the rail capacity upon which that investment depends.”
The previous Croydon Area Remodelling Scheme proposed expanding East Croydon station from six to eight platforms, improving surrounding junctions and supporting improvements at Norwood Junction. Earlier modelling suggested that resolving the bottleneck could unlock around £5.1 billion in economic value over 20 years.
The Mayor believes that the scale of investment now planned along the Thameslink corridor, including Gatwick and Luton airport expansion and the Universal resort in Bedfordshire, strengthens the case for updating that assessment.
He is asking the Government to examine the full scheme alongside phased improvements and alternative engineering options that could deliver benefits sooner and more affordably.
Mayor Perry wrote:
“I am not asking the Government to approve that pre-pandemic design unchanged. I am asking it to reopen the work, update the economic and passenger evidence and identify the most affordable and deliverable means of securing the required capacity.”
His requests include initial funding to update the business case, protection for land needed for future improvements, and a coordinated investment proposal for consideration at the 2027 Spending Review.
For Croydon, better rail connections would support the Mayor’s wider work to attract investment, create jobs and regenerate the town centre, while improving journeys for residents and businesses across the borough.
The Mayor has requested a meeting with Dan Tomlinson and his team to discuss the next steps.
The Mayor’s letter is reproduced below in full.
Dear Dan,
Thameslink Growth Corridor, Gatwick Airport and the Croydon rail bottleneck
I am writing further to my letter of 19 August to the Secretary of State for Transport, the Rt Hon Heidi Alexander MP, concerning the Thameslink Growth Corridor, the Brighton Main Line and the Croydon Area Remodelling Scheme. The letter is attached.
That letter asked the Department for Transport to commission a refreshed assessment of the investment needed to address the Windmill Bridge Junction and Croydon bottleneck. I am writing to you because this is also precisely the sort of regional growth constraint that No10 North was established to examine and help resolve across government.
The central issue is straightforward. The Government has approved one of the largest privately financed infrastructure investments in the Southeast for decades, but the public transport infrastructure needed to unlock its full economic value remains constrained by a railway bottleneck that has been recognised for many years.
Gatwick Airport’s £2.2 billion Northern Runway project has now received development consent and the remaining legal challenge has been rejected. The investment is expected to support around 14,000 jobs, add approximately £1 billion a year to the regional economy and enable Gatwick to serve as many as 80 million passengers annually. Its success depends on public transport.
Gatwick’s transport assessment records that approximately 47% of passenger journeys were made by public transport before the pandemic. The consent framework for dualrunway operations contains a target of 54%, and Gatwick has publicly acknowledged that achieving this will require action by third parties, including the Department for Transport, on rail services, timetables and capacity.
This is not a marginal consideration. Every regular rail service between London and Gatwick passes through East Croydon and the constrained junctions immediately to its north. It would make little sense for the country to approve a £2.2 billion airport investment, with major regional and national economic benefits, without properly assessing the rail capacity upon which that investment depends.
Network Rail has previously described the Croydon area as Britain’s worst railway bottleneck. East Croydon handles more trains each day than all the intercity operators serving Euston, St Pancras and King’s Cross combined. Around 18% of all national passenger journeys take place on the Govia Thameslink Railway network, yet limited platforms, flat junctions and conflicting train movements continue to restrict capacity and spread delays across the wider network.
The problem, therefore, reaches far beyond Croydon. It affects passengers, employers and investment from Brighton and the south coast, through Gatwick and London, and northwards to Luton, Bedford, Peterborough and Cambridge.
The previous Croydon Area Remodelling Scheme would have expanded East Croydon from six to eight platforms, remodelled the surrounding tracks and junctions, removed conflicting train movements and supported improvements at Norwood Junction. It was expected to create capacity for four to six additional trains an hour and provide approximately 15% more peak capacity.
Previous modelling, cited in Parliament, suggested that resolving the bottleneck could unlock around £5.1 billion in economic value over 20 years. There is good reason to believe that the potential value is now materially greater.
The earlier assessment did not fully reflect the certainty now provided by consent for Gatwick’s Northern Runway, the airport’s potential growth to 80 million passengers, or the cumulative effect of other investments and housing growth across the Thameslink corridor. Further north, Luton Airport expects passenger numbers to reach 32 million by 2043, whilst the planned Universal resort in Bedfordshire is expected to attract 8.5 million visitors annually and support around 28,000 jobs.
The £5.1 billion figure should, therefore, be treated as the starting point for a refreshed assessment, not the ceiling of the opportunity.
I recognise that the original CARS proposal was estimated to cost approximately £2.9 billion, take more than ten years to deliver and involve substantial disruption. I am not asking the Government to approve that pre-pandemic design unchanged. I am asking it to reopen the work, update the economic and passenger evidence and identify the most affordable and deliverable means of securing the required capacity.
This should include examination of the full scheme alongside phased interventions, alternative engineering options and measures capable of delivering earlier improvements. It should also establish what must be delivered, and by when, if Gatwick is to achieve the public transport mode shift anticipated through the Northern Runway consent.
I would therefore ask No10 North to:
- recognise the Croydon and Windmill Bridge bottleneck as a priority regional growth constraint;
- convene the Department for Transport, HM Treasury, Network Rail, Gatwick Airport, Croydon Council and other corridor authorities to agree a route forward;
- support an initial, stage-gated programme of development funding to refresh demand modelling, costs, economic benefits, risks and delivery options;
- ensure that land already acquired or identified for the scheme remains protected; and
- develop a robust cross-Government investment proposition for consideration at the 2027 Spending Review.
Investment in this corridor should not be seen as a local railway request or as competing with growth elsewhere in the country. London and the South East together generate around a third of national economic activity. Protecting and expanding the infrastructure underpinning that productivity supports jobs, investment and public revenues across the United Kingdom.
The immediate decision is not whether to fund the whole of the former CARS scheme. It is whether the Government is prepared to invest in the work needed to understand and remove a demonstrable constraint on billions of pounds of regional growth.
I would welcome the opportunity to meet you and the No10 North team to discuss how this work can be taken forward.
Yours sincerely
Mayor Jason Perry
Executive Mayor of Croydon
