Geoff Hobbs is a man who revels in the exciting-if-you-work-at-CityMetric title of the head of planning for Transport for London’s rail division. Last week, he gave a presentation at a Centre for London event on the future of the capital’s rail services.

In the name of full disclosure, we should admit upfront that we weren’t actually there. (Boo.) But we were watching on Twitter, and have had a good read of his powerpoint presentation. Here are some things that we learned.

1. London is growing really, really fast

By the equivalent of two tube trains of people every week, in fact. That means 50 per cent more rail trips in the capital as soon as 2031.

So far, much of that growth has been handled through upgrading the tube – bigger trains that can carry more passengers; better signalling systems that allow you to run more trains on a line; that sort of thing.

But, Hobbs’ presentation tells us, the Tube will hit a limit on this by the end of the 2020s. So – the extra capacity has to come from elsewhere.

2. Most of the growth is likely to be north of the river

Here’s where all those new Londoners are going to live:

And here’s where they’re going to work:

Much of the growth on both maps is happening directly to the east of central London, in the boroughs of Tower Hamlets and Newham. That’s not surprising: as the city’s former industrial heartland, that’s where the most brownfield land is.

But look at where the growth isn’t happening. The huge chunk of London south of the river is expected to see relatively little change.

There’s a reason for that.

3. Transport in south London is, relatively, rubbish.

We’ve written before about why the best transport maps show frequency as well as route – here’s a worked example of what such a “frequency map” would look like in London.

The lines coloured red are those you can turn up to at any time and have a pretty good chance there’ll be a train along shortly. Those coloured grey are those that you can’t. See if you can spot any patterns.

To an extent this is just a reflection of the fact the Tube, DLR and parts of the Overground are better than most national rail services. (Duh.) But since South London is disproportionately reliant on national rail services, it is – relatively speaking – a right pain to get to.

4. So it takes longer to get there

Consequently, this happens:

This is travel times from Oxford Circus. Green is relatively good; red is relatively bad.

Note the way the green areas fade out a lot quicker south of the river than north.

5. Baby steps can get you places

A number of new lines are proposed for the southern half of the capital: extensions to the northern and Bakerloo lines; Crossrail 2. But Hobbs argued that another part of the plan should be making national rail more like the underground.

That means a huge swathe of incremental improvements: simplified service patterns, higher frequency routes, the changes to the layouts of junctions that you need to allow them, trains that can accelerate and brake more quickly.

Most of these are the sort of improvements that tend to get ignored by map fanatics like us – but they can have a major impact on service quality.

Here’s an illustration of what this would mean in practice, if TfL took over the south London train services currently operated by the train operating company Southern:

At the moment, south London has a complicated tangle of different routes. In this version, they’ve been replaced by just six: two into Victoria, three into London Bridge, and one across town.

It would, Hobbs says, give nearly all the London stations on the network service frequencies of 6tph. And the only bit of major infrastructure work envisioned here would be new platforms on the London Bridge-Sutton line, to turn it into an interchange.

6. London doesn’t stop at the city boundary

We already knew this, of course, but nonetheless, this is a pretty striking map. Look at the way the city’s tentacles spread across the whole of the south east:

 

At the moment, TfL only has its eye on the “inner suburban services” – those that terminate at or near the city boundary. In the long term, though, it may make sense to give the city’s transport authority control of trains that go well beyond that.

All images reproduced courtesy of Transport for London. Thanks also to the Centre for London.