Off the tourist track: Water and Steam

Tuesday, January 16, 2018

Happy New Year! And apologies for the disruption to our regular service. What can I say? It was Christmas, and then it was New Year’s, and boat has been obstreperous, and though I’ve been back in London for over a week following my annual pilgrimage home to Canada, I honestly couldn’t tell you what I’ve done in that time other than not blog and feel jet-laggy and go for occasional short runs and binge out on Netflix. (Which I can now stream unlimitedly to my iPad or computer because mobile data package costs in the UK are awesome. Unlike in Canada. And yes, I would like some cheese with that whine). London is mostly grey and rainy and it’s all a bit… January. I did go to the Geffrye Museum one Saturday, which has been on my list for a long time. But was mostly a disaster because it took forever to get there and then it was super crowded and a big part of it that I wanted to see was closed until the next day and now it’s closed for renovations for two years so bleah.

Instead, I spent last Sunday on a succession of buses to visit the London Museum of Water and Steam, which has also been on my list, especially since Karen and I passed it en route to Kew Gardens last summer. (Karen callously refused to stop for a quick visit but I forgive her.) So brace yourself for another blog about gears and pumps and giant machinery, in the grand GSWPL tradition, (like this and this and this from the deep archives).

Slightly boring photo, but I love the cleverness of the logo design

The Museum of Water and Steam is dedicated to restoring and maintaining no fewer than FIVE historic steam-driven beam engines, as well as housing an exhibition of the history of London’s water supply. The building itself is the former Kew Bridge Pumping Station, dating from 1838 and run at the time by the Grand Junction Waterworks Company. That warmed my heart little bit, because the water feeding the pumps when the station first opened was taken from the Paddington Arm of the Grand Junction Canal, where my little boat spends most of its time these days. Though not long after opening they switched to taking water from the Thames because it was cleaner than the canals. And if the canals then were anything like they are now I’d say that was a very wise move indeed.

The Sunday afternoon I went it was pleasingly unbusy so I got to play with all the interactive models without having to elbow some snotty eight-year-old out of the way. And I got to linger at all the other displays without feeling like I was getting in anyone’s way. This means I can now relate that, astonishingly, the first piped water came to London in 1237. And that’s not a typo. In the 13th century wooden pipes were used to bring water from Tyburn spring into London. (The first piped water to private homes was in 1528.)

Wooden pipes like this were used for centuries (60 AD to 1810 according to the plaque). GSWPL fun fact!: Wooden plumbing pipes are where we get the terms “trunk line" and “branch line" from.

Wood gave way to lead (bad idea) and then to the king of plumbing: cast iron. There were also brief dalliances with steel and cement (neither as good as cast iron) but nowadays it’s all plastic. However, just like the brick-lined Victorian sewers that still handle much of London’s waste, one of the cast iron water mains at Kew Bridge is still in use today, making it the oldest cast iron trunk main still in use in the world. Along with the pipe display, the entry hall of the museum had some fun working models of different types of water pump, going back to Roman-era technology. And there was a whole wall of cisterns and toilets accompanied by various voiceovers that mostly seemed to be about conserving water which made me feel a bit smug, considering my miserly 100 litres/week consumption on the boat.

The Wall O'Toilets

When dealing with the topic of water supply, it’s also natural to deal with the other end of the system, the removal of waste water. We here at GSWPL dealt with this topic in the critically acclaimed post Off the Tourist Track: Crossness Pumping Station, so I’ll just remind you quickly of the key points: London population boom + plumbed toilets = raw sewage in the Thames + yucky smell + cholera. Therefore: Joesph Bazalgette + huge brick sewer pipes + giant pumping stations = fresh water - cholera! Everyone got that? So the beautiful beam engines at Crossness Pumping station were for pumping sewage, whereas the ones at Kew Bridge were for pumping the fresh water supply from the Thames and then out to London.

While Thames water may have been slightly cleaner than canal water, it still wasn’t exactly pristine and healthy. This led to the introduction of the first treated public water supply in 1829, engineered by James Simpson for the Chelsea Waterworks company. He used a sand filtration system, wherein water was held in large sand-bottomed basins with the water filtering down through the sand, cleaning it of impurities. Sand filtration is still used today, though it’s ironic that Simpson thought it was the sand that does the cleaning whereas it’s actually the scummy layer of gelatinous gunk that forms on top of the sand that does all the work. That layer, amusingly called the Schmutzdecke (and I promise I am not making that up because I truly could not make up so absolutely perfect a word) is home to a bunch of bacteria and protozoa and other tiny beasties that filter out 90-99% of bacterial nastiness. Kew Bridge Pumping Station used to have acres of sand filtration pools, but now that area has been redeveloped into flats. (Full disclosure: I only wrote that paragraph so I could use the word schmutzdecke. And who could blame me?)

But enough about water treatment and on to the giant steam engines! As I mentioned, the Museum of Water and Steam is custodian of five steam powered beam engines, including two absolute monsters, the Grand Junction 90 inch and the Grand Junction 100 inch. Both are Cornish engines, meaning they’re a particular type of steam engine (developed in Cornwall, unsurprisingly) that uses the steam at a higher pressure, thus operating more efficiently and using less fuel. This was important in Cornish tin mines where the pumps were used to take water out of the mines but where coal had to be shipped in from other parts of the country, hence was used as sparingly as possible. The 90 inch and 100 inch measurements refer to the diameter of the main piston of the engine. The 100 inch is the largest surviving single cylinder beam engine in the world and the 90 inch is the largest working beam engine in the world.

It’s hard to get a good picture of the engines since they completely fill entire huge rooms. So here instead is a partial shot of the outside of the Bull Engine’s cylinder, a mere 70 inches.

And a gratuitous shot of some very nice dials.

Apparently during the restoration of the 90 inch engine in 1976 the cast of Blue Peter climbed into the cylinder housing and had a tea party under the piston. So it’s, you know, BIG. The 90 inch could pump 2142 litres of water in a single stroke and the 100 inch could move 3255 litres. Working together, with their pistons alternating and synchronised, the two great engines could pump more than 63 million litres of water in 24 hours. And the 100 inch engine operated most of its working life with a crack in the 54 ton main beam - it was repaired in place and the engine continued to operate until it was last run in steam in 1958, though that was just a demonstration - by the 1940s the steam engines were no longer used for pumping water.

After looking through the chilly engine rooms I wandered into a smaller workshop where I ran into the only museum staff I encountered. The older gentleman was dressed in a boiler suit (coveralls) (Hang on a minute… steam engines... boilers... that’s why they’re called boiler suits!) and he was engaged in some sort of building task behind temporary barricades. I struck up a conversation with him, which turned out to be the most interesting part of the visit. It turns out he wasn’t doing anything really cool like aligning grappler flanges or lubricating the Boggs-Flinder Compensator. He was just hanging something on the wall, but he was very chatty and happy to share some fun tidbits about the engines and the museum.

The workshop room. Apparently there's also a Victorian-era belt driven metal working shop were they still do work for the museum. Fantastic!!! Tragically, not open to the public. 

For instance, he told me that during World War Two (after the big pumps had been sidelined by diesel and electric units) the steam engines were still kept on standby in case of a loss of power or damage during the Blitz. Since all they required to work was fuel for the boilers, lack of power or diesel would not stop them from pumping water. Keeping the water flowing was critical during the bombing not for domestic use, but because of the constant need for water for fire fighting. To support that need, a series of diesel generators ran 24 hours a day to keep the pumps running (they didn’t end up needing the steam engines) so that even if bombing damaged water mains and water was running freely into the streets in places, there was still water available to the fire brigade.

I also got an apology because some of the engines were supposed to be running in steam - indeed that’s part of why I’d gone that day - to see the machinery in action. However, all was quiet on the West London front because the volunteers who’d been scheduled for duty had been unable to attend. This was astonishing to me - that someone might have the chance to tend and run glorious machines like that and then just not come.

Sadly, even if there had been volunteers available, the restored 90 inch engine still would have been silent because there are some small repairs needed on it that involve taking the lid off the main boiler. Apparently it’s not a difficult job, but the overhead beam they want to use to lift the lid can’t be rated for the lift. (Health and Safety, you know.) Also it’s a Grade 1 listed building so they can’t really risk damaging the building in order to repair the engine. The plan now is to create a ground-supported structure over the boiler to lift the lid, but that has to sit on the York stone flagged floor which is part of the listed building which blah blah blah… you see the problem.

And along those same lines, it’s apparently quite tricky to get insurance for a building like the Great Engine House. Ownership of the site recently passed from the developers of the nearby flats to the Kew Bridge Engines Trust, who are naturally keen to have it properly insured. However, most of the time insurance companies base insurance costs on a standard formula to do with the size and purpose of a building, and obviously in the case of historically significant one-of-a-kind buildings, that formula doesn’t really apply. So apparently they’re having to consult with the folks who run other historic sights to see what they do. (“Hello is this Stonehenge? Hi, it’s Kew Bridge Pumping Station calling. So look, if the stone circle were to burn down… what would that be insured for? Hello? Hello?”)  It was all things I’d never really considered when walk-in through a museum.

Most interesting though, was the notion that there’s room for newcomers on the team of volunteers who tend the giant steam engines. That seems like exactly the sort of thing your humble blogger might enjoy very much (other than the boiler suits possibly making my ass look fat). Someone please remind me about this when I get back to London in September.

Wait, did I say BACK to London? Yes I did. It’s time again for GSWPL to decamp to foreign climes for another big show. More on that another time. Until then, there’s really only one thing to say.


1 Comment:

Kathryn said...

I definitely see you in a boiler suit.

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