What is your favorite piece of engineering?

I. One evening on Camino, my pilgrim pals and I ate dinner with an engineer.

It was hard to get a general conversation going * until I asked the table, What is your favorite piece of engineering?

It was a desperate move, to ask such an obvious question, and I was surprised how well it worked. Everyone had something to say. 

The engineer named some jet aircraft (the F7?). When he was seven, he said, he'd had a poster of it on his wall.

bink said her favorite engineering feat (also from childhood) was the step in the Egyptian mummification process when the corpse's brain is pulled out through the nose cavity.

I don't remember what I chose. I bet I talked in generalities about how I went from believing that one's spiritual life was the most important thing in life to realizing that the delivery of clean water trumps all.

Now I know that clean water relies on the proper disposal of human waste, and for my favorite engineering feat, I would be chose the London sewers, designed by sanitation hero Joseph Bazalgette in the 1850s. 

II. Black Mayonnaise

At that time, the River Thames ran so thick with the raw sewage, garbage, and industrial slough of London's 2+ million people, it was like black mayonnaise. 

LEFT: "A drop of London Water,"

 artist: John Leech, 

Punch Magazine, 1850.

While previously Londoners had emptied their bladders and bowels into chamber pots and privies (outhouses), more and more people installed the fashionable new flush toilet, which worsened the situation: 

flooded with even more wastewater, cesspools for holding ordure overflowed into the city's insufficient sewers (designed for rainwater only) and into the river. 

Bacteria loved the shitty water. Cholera flourished, and in the hot summer of 1858, the stench was so gag-making, Londoners called it the Great Stink.

____________________________________________________

In 1850 Charles Dickens described the blighted riverside, in David Copperfield:

Slimy gaps and causeways, winding among old wooden piles, with a sickly substance clinging to the latter, like green hair, and the rags of last year's handbills offering rewards for drowned men fluttering above high-water mark, led down through the ooze and slush to the ebb-tide.

The River, working drawing by Phiz (Hablot K. Browne), for David Copperfield, 1850.

III. Simple, Troublesome, Elegant

Joseph Bazalgette became the hero of the day. (Actually, it took almost two decades to complete his project.) As the chief engineer for London's Metropolitan Sewers Commission, he designed a sewer system to move the waste away from the city. He said:

"The idea was very simple. The existing streams and drains all ran down to the river on both sides. All that had to be done was to carry main sewers at varying levels on each side of the river, so as to intercept those streams."
Simple in theory, but... "It certainly was a very troublesome job. We would sometimes spend weeks in drawing up plans and then suddenly come across some railway or canal that upset everything, and we had to begin all over again."

  ––quoted in Steven Johnson's The Ghost Map : The Story of London's Most Terrifying Epidemic (2006).

Good engineering is often surprisingly elegant and beautiful, and Bazalgette's sewers are no exception:

_______________________
* "I would never talk just to be social. Now, to sit down with a bunch of engineers and talk about the latest concrete forming systems, that's really interesting. Talking with animal behaviorists or with someone who likes to sail, that's interesting. Information is interesting to me. But talking for the sake of talking, I find that quite boring."   --Temple Grandin