Think your airport link proposal is better than EARL? I'm all ears

One reader wrote to say that since this was a public sector project, it was liable to be affected by the "politician problem".

As happened with the Holyrood parliament project, politicians massage pre-construction estimates down, to reduce potential opposition.

Holyrood was also hit by unexpected and costly problems, such as the need to increase security and bomb-proofing in the wake of the 2001 terrorist attacks on the US. And it was a bizarrely procured scheme where the taxpayer bore all the risk and the contractor did not.

EARL, which is still alive, at least until September, is quite unlike the Holyrood project. The cost estimates have not been tampered with by politicians, but were drawn up by consultant engineering firms.

The recent report by the Auditor General pointed out that the 633m estimate contains a 104m allowance for optimism and risk - money that might not have to be spent if everything goes to plan. In other words, there is already an allowance in for cost overruns that, in any event, are a lot less likely than in the Holyrood project because the design is not likely to change and the contractors will bear some of the risk.

Another reader, Michael McTighe, said that while at the airport recently, he spotted the Edinburgh-Fife rail line running past the eastern end of the runway. He wrote: "I wondered why our engineers could not tap into that line instead of having to build a tunnel. The powers that be have surely thought of this one, haven't they?"

Yes, indeed they have. A report produced by Transport in Edinburgh (TIE) earlier this year has come my way. It looked at putting a station beside the old Turnhouse terminal now used for cargo.

This could then be connected to the Glasgow line by a new curve linking the Fife line to the rail line in the north side of the airport.

One problem with this is that passengers then have to get to the airport terminal, which is three-quarters of a mile away.

So four options for taking them there were looked at: a shuttle bus using public roads, a travellator in a tunnel under the old Turnhouse runway, an underground driverless shuttle train, and a shuttle bus using a fenced off route round the airport perimeter.

This last option was totally ruled out by BAA, the airport's owner. BAA says that, because the Turnhouse runway, which has to be used occasionally for flights, is a bit on the short side, there is not enough room for a fenced-off bus route. Security problems such as passengers and baggage having to be screened between train and bus also rule it out.

The cheapest of the remaining options is the Turnhouse station plus bus shuttle using existing public roads, estimated to cost 114m.

The journey time from Edinburgh city centre to check-in desk, however, allowing for getting off the train and onto a bus, is reckoned to be 65 minutes, twice as long as the existing airport bus service.

A station plus underground travellator is more expensive - 321m - but the centre-airport trip would be a tiny bit quicker at 62 minutes.

The underground driverless shuttle is even more expensive - 415m - and the journey time 64 minutes.

Compare these with the journey time expected on the EARL project, 31 minutes, and it doesn't take a transport expert to work out that a lot fewer people are likely to use them.

True, people coming from Fife and Tayside would probably use them, but the modelling suggests that usage would be half that of EARL and that a continuing subsidy would be required, which EARL does not need.

The TIE report does note that the company has been accused of manipulating the data to make EARL look good, but it also adds that models and processes used in these appraisals were "subjected to rigorous scrutiny by economists of the Scottish Executive".

So it looks pretty conclusive that the alternatives to EARL may be cheaper but are much worse value for money.

Hmm, says one of my indefatigable correspondents, Bruce Skivington, those problems of linking the Turnhouse station to the terminal could be solved by moving the entire terminal to the present cargo terminal on the west side of the railway line.

He reckons that a brand new terminal should not cost much more than 100-150m. This would have to be paid by the taxpayer, since BAA would quite rightly point out it already has a perfectly good terminal.

Add the other costs of new roads, car parking, converting the old terminal for cargo, etc and you might be able to do the whole thing for about 300-350m.

Skivington adds that, after the Glasgow airport attack, you could design the terminal to be car-bomb-proof by putting all the parking and drop-off areas to the east of the line.

Well, maybe, though the three to four-year delay that would be caused by the need to hold public inquiries, etc., might make this more costly than it looks.

Though I'm highly sceptical, it might be worth somebody doing some serious costings.

Anybody got any further thoughts?

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