Last week, the Centre for London published a report calling on Transport for London (TfL) to take over South London rail services.

The vision the think tank outlined in the “Tuning South London Orange” report would mean replicating the successful transformation of fragmented, underutilised and disconnected urban rail infrastructure into the popular London Overground orbital. This would mean better public transport for South London; that in turn would unlock the capital’s housing development and growth potential.

The London Overground brand was born in 2007, when TfL took on responsibility for the orbital North London and Gospel Oak to Barking lines, and the suburban radial route from Euston to Watford Junction. The network expanded when the revamped East London Line was reopened in 2011, and again when the orbital completed in 2012.


Other routes, in the north east of the capital, have been added since. All these routes are now shown in orange on London’s rail maps.

Last week’s report argues that adopting the same model could improve services and increase capacity in South London. London Overground’s orbital demonstrated how rail investment encourages greater densification, as the better transport connectivity makes locations more attract to live in. So, better rail services could also enable more housing along South London’s rail corridors and focused around stations.

With large population and employment growth is forecast for London, policies to address the pressing issue are particularly timely. The Centre for London estimates upgrading the South London rail network to “orange” standards could add 16,000 new homes to this area – an increase of almost 79 per cent.

Counting the cost

There were several keys to the success of the new London Overground: new connectivity, more frequent services, greater awareness of the network and links between previously poorly connected location. The key changes that were undertaken for the “original” London Overground orbital were:

  • Increasing service frequency to at least 4 trains an hour;
  • Integrating the new network into the existing public transport network with integrated ticketing, interchanges and maps;
  • Running new “metro”-style trains;
  • Investing in the fully staffed station.

London Overground transformed connectivity along its route. Passenger numbers on these services have quadrupled since TfL started managing the service in 2007 – testament to the transformative nature of these improvements. In the first four years alone, ridership rose 80 per cent. Importantly, passengers have consistently rated London Overground amongst the highest in the country for customer satisfaction.

The developing London Overground network (click to expand). Image: Centre for London/TfL.

The report’s authors envisage these same “orange” standards being applied to the entire South London rail network. But the proposed changes would require substantial investment in the South London network to replicate the London Overground’s success.

The costs bringing “turn up & go” services (that is, those which run at least four trains per hour) is estimated to be somewhere between the £6.5bn cost of the Thameslink programme and the £14.8bn of building Crossrail. This project is also likely to take 20-25 years, and the costs would be spread across the time period.

This would make Turning South London Orange the fourth largest rail project ever undertaken in the capital after Crossrail, Crossrail 2 and High Speed 2. By comparison, it cost TfL approximately £1.5bn to upgrade the “original” London Overground to “orange” standards.


A question of frequency

South London’s suburban railway network largely dates back to the Victorian era. For it to perform like the London Overground will require considerable investment – to upgrade signalling, amend track geometry so more trains can run (for example, replacing flat junctions with flyovers), introduce metro-style trains and improve the stations.

These network wide upgrades are necessary to deliver a service a higher frequency service, including a minimum peak frequency of six trains per hour. They should also help reduce “dwell time” – the time trains spend at the stations – which the report describes as a “critical limit” on high frequency networks.

One key to creating a more frequent service will be to rationalise service patterns for South London. At present, many stations in the area have two or more sets of (low frequency) services, serving multiple terminal stations. The Centre for London report suggests funnelling all services on particular branches to either Victoria or London Bridge – but not both – to create service frequency of 14 to 18 suburban trains per hour on the inner parts of the line.

Institutional barriers

So even if TfL were to take over the south London rail franchises, there would be a lot of work needed to deliver the vision of turning south London orange.

For one thing, the national government’s Department for Transport must devolve power to specify, let and manage the network to the capital’s transport authority. This will allow TfL to specify “orange standards”: frequency, station staffing and trains.

A reform in governance of this kind was necessary for the creation of the current London Overground network. The transfer of responsibility will allow TfL to directly invest in the network, through station and track upgrades.


One potential challenge to the shift of power to Transport for London is that a number of stations on the routes earmarked in the report for “orange” standards are not within the Greater London Authority’s boundary, and therefore not under the mayor’s or Transport for London’s jurisdiction. Neighbouring county councils have blocked such reforms in the past.]

However, Kent and Surrey councils have both signalled support for the proposal – on the condition that services to their constituencies will not be negatively affected by management changes. Watch this space.

Nicole Badstuber is PhD Researcher and Research Assistant in Transport Policy and Governance at University College London at UCL.

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