Over at CiF, Frank Fisher, the Big Blogger winner knows as Pike Bishop, make a pretty decent fist of a critique of the government’s plans for roadpricing…
Sir Rod Eddington’s transport report suggests road pricing is the only way to solve Britain’s gridlock crisis – an “economic no-brainer” he reckons; coincidentally it’s the route that also guarantees massive receipts for the Exchequer, and a fabulous new surveillance system for the Home Office – little wonder politicians seem keen to embrace the big vision.
Eddington claims that road pricing will deliver £28bn a year to the UK’s economy – in fact, his assumption is that if congestion were to vanish totally business would save that sum. Of course, additional cash will also be generated: tariffs levied on motorists. Is anyone convinced the government will reduce other taxation to make this a tax-neutral measure? I thought not. But regardless of the financial impact on motorists, where poorer motorists will be hit hardest, and also the privacy argument (I’ll come back to that), is road pricing in fact the only way to cut congestion?
There is, however, another, rather fundamental problem with this whole scheme that no one seems yet to have noticed, and as you might expect from debates such as those surrounding ID cards, its technology that’s the problem.
It’s a matter of accuracy. If the government is going to charge you a toll for using certain roads, then you want to be damn certain that you’re only paying for your actual usage. The bill has to be correct.
And therein lies the problem.
You see, the technological ‘hub’ of this system, it has been suggested, will be a GPS tracking system fitted to your car, which will report your mileage, speed (think of all the tickets) and which roads you’ve used back to the government, so that your bill can be compiled an issued.
But, there’s a but in all this, and its a big one.
You GPS system are not 100% accurate – the location they provide is subject to a margin of error arising from a variety of different things, including atmospheric interference, multi-path errors (signals bouncing of nearby buildings and structures) and clock/timing errors.
A standard GPS system is accurate, as a result, of a margin of error of between 4 and 20 metres – best case is usually cited at 15 metres.
Now this may present few difficulties in tracking cars whizzing along the motorway, but in urban areas this error may cause considerable problems.
Consider the following scenario – two roads running roughly parallel to each other, one a main road into town and subject to road pricing, the other a minor road running through an estate for which there is a minimal or zero charge.
These roads are separated by a distance of around 10 metres, run parallel to each other for half a mile and eventually ‘meet’ at set of traffic lights (i.e. one can turn off the minor road at a junction which take you up to the main road at another junction.
A car travels up one of these two roads at thirty mile and hour – how can a system with a best case accuracy of 15 metres, be certain as to which road the car is on, and therefore what, if anything, they should charged for that portion of their journey.
This scenario is not only possible, but very likely be played out every day in Britains crowded towns and cities, if roadpricing is introduced.
Yes, the accuracy of GPS tracking can be improved, down to an accuracy of between 1 and three metres, but such improvements are not cheap by any means, requiring fixed base stations as well as satellites – and most of the technology is currently either still experimental or in use only by the military and/or aviation industry. And data from other systems (ANPR) could be used to improve accuracy as well, but there are still limits – 100% accuracy would be attainable only if every single chargable road were covered by an ANPR system – and how much would that cost?
As with biometrics on ID cards, the government are, again, pinning their future policy on the belief that ‘technology’ will provide – but what if it doesn’t.
What if the costs of a system with the necessary degree of accuracy prove to be prohibitive? Or if it simply proves impossible to attain the necessary level of accuracy in typically British urban conditions? What then?
A road-pricing scheme based on a tracking system that can’t tell exactly what road you’re on and, therefore, what you should be charged, is completely useless.