Monday, November 01, 2010
There are 2 Forth bridges at Queensferry. The original one is the iconic railway bridge.
Sir John Fowler and Benjamin Baker designed a cantilever bridge in steel, with three diamond-shaped towers.Having previously pointed out that the current road bridge cost £320 million in today's money (£19 million in the sixties) while the proposed new one is costed at £2.3 billion (previously four & a half billion) I think a further comparisonof the original in today's costs is in order.
The bridge was built by Sir William Arrol. Constructed started in 1883. The bridge was opened in 1890 at a cost of £2.5m. It is still in use today, carrying the railways to the north from Edinburgh. more here
£204,000.00 using the retail price index
£261,000.00 using the GDP deflator
£1,230,000.00 using the average earnings
£1,470,000.00 using the per capita GDP
£2,420,000.00 using the share of GDP
The one that matters is the retail price index. So it comes in at 2/3rds the cost of the original road bridge. Since the rail bridge was naturally built on the shortest & easiest crossing, using natural rocks as tower foundations & provides 2 rail tracks rather than 4 road carriageways that looks like £320m for the road bridge is better value for money, though not enormously better, than £204m for the rail one. This is what one would expect since inflation at the cutting edge of technology is usually less because that cutting edge moves forward over time. However it makes a further nonsense of the government's claim that their prices cannot be compared with the rest of the world's bridge costs because of the "unique geography" of the Firth of Forth.
I note, however, that the cost of the original bridge is very close to the proposed new one as a share of GDP & thus a proportionately equivalent drain on society. This is, at the very least, strongly compatible with government having made an assessment of how much public blood is available for draining & with us so much richer now coming up with a proportionately similar amount to the 1890s figure & deciding that is the figure they can get away with.
Oh and the Victorian bridge hasn't fallen down either. It being, nominally, this fear which requires us to replace the road bridge.
I've just been reading the information commissioner's decision upholding transport scotland's decision to withhold the information on the rates of pay for the consultancy management commission for the proposed new crossing of the Forth, as requested by Tom Minogue. The crucial clause ( it seems to me ) is "would discosure of the information cause, or be likely to cause substantial harm to a legitimate economic interest". How can secret contracts with unspecified duties,rewards, and measures of performance be other than illegitimate and a conspiracy against the common good. It seems very difficult to get a copy of exactly what the commission's brief is, and if Transport Scotland's website is any guide, reinforcing, refurbishing and developing the existing bridge have been summarily dismissed and not explored as options by a genuinely independant group of professional engineers. regards Sandy