For some years now I’ve been making the case that the proposed additional Forth Road Bridge would be unaffordable, unsustainable, unnecessary and unpopular. The existing bridge has been undergoing a dehumidification programme, and today the signs are they’ll find that’s working.

As the Scotsman puts it, this would “call into question the need for a new bridge costing as much as £1.6 billion“. Bear in mind that even if the final dehumidification results show serious deterioration, the bridge could still be recabled for a maximum of £122m (I believe that’s at 2008 prices but I could be wrong). Simple prudence.

Every party at Holyrood apart from the Greens lined up to give Fifers what they think Fifers want: yet another shiny new bridge. No-one at Holyrood apart from the Greens was prepared to say let’s wait and see, let’s not sign contracts for a bridge which has been variously estimated by Ministers to cost £1.6bn to £4.2bn until we know if it’s really necessary.

Despite the clear warnings from transport experts, the four-party consensus refused to listen, and now contracts have been signed to squander vast sums just as the public finances are being squeezed by Tory and SNP cuts (as per the Sun’s endorsement of the SNP because they were “tackling the economic crisis head-on by cutting public spending faster than anywhere else in the UK“).

Even now, just as it looks as though we’re about to see confirmation that even recabling won’t be necessary for the existing bridge, the other parties are still not ready to see sense. Some are still gung-ho: certainly the Nats and one would imagine the Tories too. The Lib Dems are wringing their hands – see Gordon Mackenzie quoted in today’s Scotsman – but won’t say no. Malcolm Chisholm admitted on Twitter that “We almost certainly made the wrong decision on new Forth Bridge but it is too late now unfortunately“, adding “Woudl we could  spend the billion plus new Forth Bridge money on new socially rented homes” (sic). Amongst non-Green MSPs and former MSPs, only Lord Foulkes also comes out with any credit, having told the Public Audit Committee last year it would prove a waste of money, although abstaining on the final vote was hardly a courageous stand.

Again, quoting the Scotsman’s editorial, “The cost of the misplaced rush to give priority for the bridge has been substantial.” Yes, true. The cost of cancellation would now be large, but nowhere near as large as the cost of proceeding to build this monument to political short-termism and idiocy. On a guess that cancellation would cost £200m – it should cost nothing but the work done if the contracts had been sensibly written, but that seems implausible – we’d still save upwards of £1.4bn: a massive slice of Scottish capital budgets.

If no sense is seen, it’s simply going to be extra road capacity which, as we know, generates extra traffic. And the years and years of disruption it’ll cause to traffic has already begun as I found out when driving over the existing bridge last week, for the first time in a very long time. Ironically, the congestion costs around repair were always accounted for very generously while the congestion cost of a new bridge was apparently never calculated. Ministers are about to find out that not calculating it isn’t equal to not experiencing it.

In December 2008 my view was that this utterly preposterous vanity project was the most likely way for the SNP to be ejected from office. Now, of course, losing a referendum is top of that list. But this bridge still isn’t far behind, and it’s closing, too. They may even interact with each other. In two years’ time we’ll be mired in a construction phase that’s unlikely to be going smoothly, just as Ministers are asking people to trust their judgement in a referendum. If even one other opposition party found a spine they’d be calling for a public inquiry into what Ministers knew when, and what advice they were given. Tragically, on this issue, Labour, the Tories and the Lib Dems are exactly as inept as the SNP. And so Scotland may well be stuck with the most expensive white elephant since the Darien Project.