EDITOR’S NOTE: This article originally incorrectly stated that the new bridge had yet to gain planning permission on the South Bank of the river. We are happy to make this correction.

One of the great mysteries of contemporary London is how the Garden Bridge project came to be so hated. Gardens are nice. Bridges are nice. Even Joanna Lumley, if you’re into such things, is nice.

And yet, at least among the sort of people inclined to bang on about municipal politics on social media, the Garden Bridge seems to have become an icon of everything that is wrong with contemporary London: money thrown at functionless nicknacks for tourists and the rich corporations, and designed by the authorities’ mates, even while the city’s real problems go unsolved. It takes impressive PR skills to turn what is essentially just a park into the infrastructure equivalent of the Masque of the Red Death, but somehow the Garden Bridge’s backers have done it.

Anyway, for the reason, the publication of the Garden Bridge Trust’s accounts yesterday caused rather more excitement than some numbers from a charity normally would. The Trust has tended to respond to all stories about them with bland assurances that everything is just peachy (honestly, they once asked me to add a clarification to what was very obviously a joke story), so you might expect the news to be good.

The news is not good. The accounts, which cover the 17 months to March 2016, and are put together by the charity’s trustees – effectively, its board, rather than its management – conclude that the project is in serious trouble. The key line in the introduction by the trust’s chairman, Lord Mervyn Davies, is this:

“Due to the material uncertainties in existence ahead of finalising these accounts, trustees are unable to conclude that the trust is a going concern, and feel it only appropriate to flag these risks in this report.”

“Not a going concern” is exactly the phrase you want people reading just before you ask them to donate to your infrastructure project.

So what’s gone wrong?

The costs have soared

The project was expected to cost £185m. Its actual costs are now likely to “substantially exceed” that.

The project still needs more public support

One of the hurdles still to be overcome, Davies notes, will be to get mayor Sadiq Khan to promise to honour the pledge made by his predecessor that the London city authorities will guarantee the bridge’s future maintenance costs. It’s unclear, to say the least, that Khan has any intention of doing this. More likely, in fact, he’s trying to cancel it by stealth.

Donations are down

Even to cover the £185m, the Trust would need to raise another £56m. Yet in the 17 month period covered in the accounts, the trust raised just £13m in new private donations for the bridge. At that rate, it’s going to take years.

The clock is ticking

And the project doesn’t have years. The planning consent the bridge has on the north bank of the river, from Westminster council, expires in December 2017. (It also requires a deal to be in place to guarantee maintenance costs, hence the pressure on Sadiq Khan to do what Boris Johnson promised.)

So – the Garden Bridge Trust needs to find substantially more than £56m, get more planning consent, and persuade the mayor the project is worth throwing more money at, all in the next few months – otherwise, the whole thing is dead. Good luck with that.

It’s a shame, in its way. The Garden Bridge should be lovely: a new park, in a part of London that’s short of them. But it probably isn’t going to happen – and the project’s chequered history mean that many won’t mourn when it doesn’t.

Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.

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