Monday, 12 September 2011

In 2010 did more people cycle over Blackfriars than TfL predicts for 2012? Is TfL trying to hide increase in cycling from London's politicians?

TfL data - share of people using Blackfriars junction %
According to Transport for London, once the new station at Blackfriars opens, there will be plenty more pedestrians using the junction at the northern end of the bridge.

One of the justifications they have used for the design of the junction is that a vast increase in the number of pedestrians means they need to make it a better place for walking. I absolutely agree with that.

What I totally disagree with is the way that Transport for London continues to try and justify the way it marginalises people on cycles at this junction. As The Campaign for Better Transport says about Blackfriars "is right to improve facilities for pedestrians at an enlarged and improved station but there is no objectivity in the balance between the needs of all modes. The ‘balance’ is driven by policy choices." Those policy choices are in favour of motor vehicles, over the majority of people using this junction.

TfL recently released a copy of the report that it presented to London Assembly Members to justify its road design. I first commented on the report a couple of weeks ago here.

One feature of the report to the London Assembly's politician's is TfL's claim that a massive jump in the number of pedestrians means that the number of people on a cycle will drop from 9% of all users of the junction to 6% - a one third drop which compares with a two-thirds drop in the number of cars and light goods vehicles.

In a separate freedom of information request statement, TfL has told the London Cycling Campaign that "Both the April and May 2011 proposal were designed to accommodate an estimated six per cent of people travelling through the junction by bicycle."

I am trying to find out how TfL works out that 6%. Somehow it doesn't quite feel right. I'm hoping to see what raw data they have based their assumptions on but in the meantime, here are my very rough calculations that explain why I think TfL is under-estimating the number of people who cycle here.

TfL states that "an essential new road layout on Blackfriars Bridge ...will be capable of handling the 40,000 passengers expected to leave the upgraded Blackfriars station every day".

The eastern side of Blackfriars. No priority for
pedestrians here, only for motor racing
So, let's assume all 40,000 of those passengers both leave Blackfriars and then come back again. And let's assume one-third of them leave via the new south bank exit. Let's also assume a further 10,000 people use the junction on foot but not the station each day. And we have 70,000 pedestrians in total.

TfL uses 2008 as its base year in the chart above. In 2008, only 4,000 people crossed Blackfriars Bridge on a cycle each day. But by 2010, that had jumped to over 6,300 people using Blackfriars Bridge on cycles. That excludes people crossing the junction from east to west so let's assume 7,000 cycles in total. Plus a further 33,000 motor vehicles, according to TfL. If you add 70,000 pedestrians (2012 forecast), 7,000 cycles (2010 actual numbers) and 33,000 motor vehicles (2010 actual numbers), you get 110,000 'people' moving through the junction a day and cycles equivalent to 6.3% of that total.


So, when TfL claims cycles will make up only 6% of the total number of people using the junction in 2012, I reckon that if TfL had modelled the number of cycles in 2012 using 2010 data as its starting point, rather than 2008 data, then it would probably show the percentage of people cycling was already more than it predicts for 2012.

In other words, by using 2008 as a starting point, TfL is telling London Assembly Members that there are thousands fewer people cycling on this bridge than there are in reality.

I realise my numbers are fairly sketchy. But they hint that TfL may be underestimating the percentage of people who cycle over the bridge. It is certainly choosing not to show the extent to which cycling has increased here in the last couple of years.

In a broader context, this suggests is that TfL is justifying not creating proper cycle infrastructure by claiming there are fewer people cycling here than there actually are. And it perpetuates that claim by showing forecasts that may be lower than figures recorded last year. 

In that context, it's not all that surprising therefore to see TfL's response to one part of the London Cycling Campaign's freedom of information request:

"Question: Cyclist modelling report for the Blackfriars junction used in preparing the initial and revised plans for the Blackfriars junction.

TfL answer: TfL does not undertake separate modelling studies for the different traffic modes.  Cycling was incorporated into the wider traffic modelling for the scheme as illustrated within our traffic models previously requested and provided to you."

Kind of says it all really.