I set my alarm for half past four, which is not something I do willingly or well. But there are mornings that announce themselves in advance — mornings that send out written invitations — and this was one. The Thornhill Star would make her first crossing at six. I wanted to be in the queue.

I was not alone. The queue began forming before five, in the dark, on an embankment that has served no particular purpose for as long as I can remember. People stood in it with the quiet determination of pilgrims — though pilgrims, as a rule, are not carrying briefcases and checking their watches. These were commuters. They had somewhere to be. They had had somewhere to be for twelve days, and for twelve days the river had been in the way.

A river is a marvellous thing until you need to cross it. The Ashwater is not wide — a competent swimmer could manage it in minutes, though the current and the temperature discourage the experiment — but it has been, since the Fernwick Bridge closed, as impassable as a mountain range. Fourteen thousand people cross it daily. For twelve days, they have crossed it by going around it: up to the Coldharbour Viaduct, over the hill, down the other side, forty extra minutes in each direction, arriving at their desks with the particular exhaustion of people who have been inconvenienced by infrastructure.

Infrastructure. There is a word that makes eyes glaze. But at five in the morning, standing on an embankment in the fog, watching the Thornhill Star’s lights come on, infrastructure is not abstract. It is the boat. It is the pontoon. It is the ticket in your pocket that costs thirty centimes and buys you fifteen minutes instead of an hour.

Thirty centimes. A tram ride costs fifty. A coffee at Rensler’s costs four hundred. The ferry, in the arithmetic of civic pricing, is practically a gift — a subsidised crossing, underwritten by the Municipal Treasury, because someone in a committee room decided that getting across the river should not be expensive. This is, in its quiet way, a radical proposition. The city has decided that the river is not a toll. It is a fact of geography, and facts of geography should be managed, not monetised.

The horn sounded at six. I will not pretend I was not moved. The sound carried across the water and bounced off the far bank, and 193 people shuffled forward with their passes and their coins, and the Thornhill Star drew away from the embankment into the grey morning, and for the first time in twelve days the Ashwater was not a barrier. It was a crossing.

Fourteen minutes. The fog thinned. Bramblegate Steps appeared. There was applause — brief, undirected, the kind that happens when people acknowledge that something is working. The gangway came down. People walked off the boat and into their mornings.

I stayed aboard for the return crossing. I had nowhere to be. The thirty centimes entitled me to stand at the rail and watch the river pass beneath a vessel that, until yesterday, was a contract and a tender and a line item in a budget. Now it was a boat, carrying people, and the distance between paper and reality was exactly fourteen minutes.

My neighbour Doyle, who is a plumber and therefore understands the movement of water better than most, said to me last evening: “They’re building a ferry to cross a river they’ve already got a bridge for. Only the bridge doesn’t work.” He meant it as absurdity. I heard it as poetry. A city that builds a new thing because the old thing broke. A city that does not wait for perfection but crosses the river with what it has.

There is a buried waterway beneath Bramblegate Steps, I am told — a conduit built in 1782, still flowing, unknown and unmapped until a surveyor named Strand followed the water and found where it goes. The river nobody named, emptying into the river everybody knows, beneath a wharf that was doing nothing until last week and is now doing everything.

Bobington is a city of crossings. Today we made a new one. Thirty centimes. Fourteen minutes. The beginning of something that is, by design, temporary — a ferry that runs until the bridge is mended, a solution that exists because the real solution will take a year.

I suspect the ferry will be missed when it goes. Things that are temporary have a way of becoming beloved precisely because they are temporary. The ferry is not the bridge. But it is the crossing, and this morning, that was enough.