It doesn’t all just happen by magic, y’know. From lakes of fine wine to mountains of animal poop, there’s an awful lot going on behind the scenes at London’s world-famous landmarks that might surprise you. David Clack gets down to the eye-opening nitty-gritty of one of this great city’s greatest structures.
How it opens
1. In a street-level control room, one of the bridge’s six technical officers presses a button to activate a public address system that alerts bridge crew (all 88 of them) to stand clear of moving machinery. They do so, on the grounds that they don’t wish to die horribly.
2. Another button is pressed that changes the traffic lights, brings down road barriers and summons staff to close the walkways. The combined sound of locals tutting and tourists cooing can be heard for miles around.
3. A third button is pressed that releases the four bolts holding the bascules (that’s the flappy bridgey bits) in place. Hank and Joan from Milwaukee and 400 Italian children squeal in delight at the resulting clunk. Everyone else is already checking Facebook.
4. A lever is pushed to engage a complex system of hydraulics and counterweights. The guy patiently waiting in his boat smiles sheepishly as the bascules slowly rise to a steep enough angle to let his massive mast pass through.
5. The whole thing happens again, but in reverse, including the tutting and cooing.
The river rules
Under an act of Parliament, boats have right of way over car traffic. So no matter who’s about to drive over, they have to wait for boats to come through. In 1997, motorcade containing Tony Blair and Bill Clinton was separated by the bridge, despite a call from Scotland Yard.
Nuts and bolts
The bridge took 432 Victorian labourers eight years, 31 million bricks, 2 million rivets and 22,000 litres of paint to build, at a cost of more than £100 million in today’s money. Worth it? It’s backdrops like this that selfie sticks were made for.
All in a day’s work
The bridge’s team of technical officers earn a salary of around £40k, and work in a strict shift pattern of seven days on, three or four days off.
Before the bridge opened in 1894, Thames crossings in the area were made via the Tower Subway foot tunnel. It closed in 1898, presumably because it was slightly less fun to take photos of.
Fancy yourself as London’s next superstar stuntman? Don’t forget your protractor – the maximum angle the bridge opens to is 86 degrees but it’s best to time your jump for when the bascules are at an angle of 30 degrees*. Maintain a steady pace of 25mph* and you’ll clear the eight-metre gap no problem. But obviously don’t – you’ll get told off. Again.
*Another top fact calculated by Time Out’s astrophysicist Jenna Thornton
A grand total of 40,000 people cross the bridge every single day. That’s a lot of matching backpacks.
The bridge opens, on average, three times a day. Any vessel with a mast over 30 feet tall can request to pass through for free, although you’ll need to give 24 hours’ notice by email (or, for retro lolz, fax).
Since 1976, the 1,100-tonne bascules have been powered by hydraulics rather than steam-driven accumulators. Some of the inactive steam machinery remains and can be seen in an exhibition in the Victorian Engine Rooms beneath Tower Bridge.