Sadly the idea of building a high speed rail line from North to South is in the news again. The idea is to spend £30bn or so building a new line from London to Birmingham. This will cut journey times, and increase capacity.

There are three reasons to oppose this plan: money, time and capacity. The first is that it is very expensive. £32bn is about £1000 per household. None of the advocates of the rail line claim that taxpayers will see a financial return. It is a bill that many in Britain can do without.

£32bn buys you a cut in journey times of 20-30 minutes. Birmingham will go from being just over an hour, to just under an hour. The distance - and so the cost - means that Birmingham - London will never be core commuter territory. The time saved is primarily for business people.

In fact, a third of all the transport benefits turn out to be time saving for business travellers! The largest group of these are London based business people. Since fares will be the same on the new line, business people are being given something for nothing, while taxpayers pick up the bill (table 1 & 2, pp. 10-11). There is no reason in the world why government should subsidise business people to travel more quickly.

Third, the government talks a lot about capacity problems. Yet the reality is that the lines from London to Birmingham and Manchester are not, by British standards, highly used. The Office of the Rail Regulator records how many people have to stand each day on their way into London. Around 2,100 people have to stand on their way into Euston. That sounds bad, until we learn that 29,000 stand on their way into London Bridge, and 27,000 on their way into Waterloo. In fact, of the 12 London terminal stations, nine have more people standing than Euston.

Even if the number of people coming into Euston doubles, and even if all of those extra are on services with no seats, and even if we add no more capacity, Euston would still be less overcrowded than services to London Bridge or Waterloo.

The reality is that a new high speed train line is the sort of glamorous project that gets ministers lots of headlines, irrespective of the benefit to cost ratio. It is exactly the sort of project that should not go ahead if we are committed to evidence based policy making.

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