Affordable Housing Institute : US

[Continued from March 6th’s Part 4, and the previous Part 1, Part 2 and Part 3.]

 

[Editorial justification for the tour: If we want to improve slums, we have to see them as ecosystems – spontaneous self-generated communities, self-organized, economically rational, economically efficient, adaptive and robust.  We may not like the slums (like Dharavi in Mumbai, Kibera in Nairobi, or Sao Paulo's favelas) we may wish them away or wave our hands (or our bulldozers) to disappear them.  Yet they will return, resisting our efforts almost as if conscious, unless we see them as organic and dynamic, and come to understand how a slum dies. – Ed.]

 

As previously posted, Steven Johnson’s excellent book The Ghost Map, which tells the story of John Snow’s proof of cholera’s transmission, also provides us with a fringe benefit comprehensive tour of the ecology of a Victorian slum.  Now we can tell the dramatic story of the 1854 cholera epidemic, and Snow’s brilliant solution. 

 

John Snow: a man who enumerated and mapped

 

When the outbreak hit, Snow, a biologist and amateur sociologist as well as a courageous man, elected to go into the heart of the outbreak area, from house to house, interviewing the residents. 

 

SDI’s enumeration of Santa Cruz: every household, every family

 

This is exactly the same critical work done by Mumbai and around the world by savings co-operatives that belong to Slum Dwellers International – and one of the many reasons I find SDI’s work so important.

 

Jockin pointing to SDI’s map of the Santa Cruz neighborhood near Mumbai Airport

 

As he did, he produced a map (later praised in Edward Tufte’s Visual Display of Quantitative Information) showing the streets, houses, pumps, and deaths:

 

Snow’s first cholera map

 

Snow was convinced that cholera was a waterborne disease that humans could not catch through breathing contaminated air, but did catch through drinking. 

 

A graphically better map showing deaths and pumps

 

Yet Snow was an outsider, neither a celebrated academic nor an aristocrat, and the likes of Edwin Chadwick utterly dismissed his findings, fixated as they were on the malodorous theory that ‘all smell is disease.’  Eventually Snow added a feature to his map: a Voronoi diagram that divided London into districts based on which public well was closest.  Overlaying the Vorondoi boundaries onto his well map produced this decisive graphic:

 

The decisive Voronoi map – irregular line denotes the Broad Street Well’s service area

 

Bingo. 

 

Nearly all the cholera deaths were inside Broad Street’s Voronoi reach; only a tiny handful were outside (and those virtually on the boundary line).  In a visually incontrovertible way, the Voronoi map demonstrated the correlative link, and led to Snow’s dramatic action:

 

He removed the handle from the Broad Street Pump.

 

Remove a two-foot length of iron; save hundreds of lives

 

The epidemic stopped within days.

 

Though Snow’s action directly saved lives, its great impact was on the city of London, which now realized it had no choice whatsoever but to add costly municipal infrastructure.

 

9. Infrastructure and municipal government

 

Unfortunately for storytelling, Snow’s findings did not immediately lift the scales from Edwin Chadwick’s eyes, but gradually, over the ensuing years, his science took hold.

 

After years of bureaucratic waffling, the [1858] Great Stink finally motivated the authorities to deal with the crucial issue that John Snow had identified a decade before: the contamination of the Thames water from sewer lines emptying directly into the river.  The plans had been in the works for years, but the public outcry over the Great Stink had tipped the balance. 

 

Money is found for slum clearance when the slums’ existence imperils or discomfits our own bourgeois lives.  It is so in today’s Sao Paulo, and it was so in Victorian London:

 

Slum upgrading in middle-class self-defense: the Guarapiranga project in Sao Paulo

 

With the help of the visionary engineer Joseph Bazalgette, the city embarked on one of the most ambitious engineering projects of the nineteenth century: a system of sewer lines that would carry both waste and surface water to the east, away from Central London.  The construction of the new sewers was every bit as epic and enduring as the building of the Brooklyn Bridge or the Eiffel Tower. 

 

Bazalgette standing atop his soon-to-be-buried monument

 

Its grandeur lies belowground, out of sight, and so it is not invoked as regularly as other, more iconic, achievements of the age.  But Bazalgette’s sewers were a turning point nonetheless: they demonstrated that a city could respond to a profound citywide environmental and health crisis with a massive public-works project that genuinely solved the problem it set out to address.  If Snow and Whitehead’s Broad Street investigation showed that urban intelligence could come to understand a massive health crisis, Bazalgette’s sewers proved that you could actually do something about it.  Pages 207-208

 

Political action comes when there is political capital, which arises from a combination of technical feasibility and voter imperative.

 

North of the Thames, the plan for the new sewers involved three main lines, each at different levels of elevation, running eastward parallel to the river.  On the south side, there were to be two main lines.  All the city’s existing surface water and waste lines would empty into one of these “intercepting” sewers, and the contents would then flow—and in some cases be pumped—several miles east of the city.  On the north side, they drained into the Thames at Barking; on the south, the outfalls were located as Crossness.  The sewers only discharged into the Thames during high tide, after which the seaward pull of low tide would wash the city’s waste into the ocean.  Pages 207-208

 

Creating a subterranean network one massive excavation at a time

 

It was a demonically complicated undertaking, given that the city already had complicated infrastructure of pipes and rail stations and buildings—not to mention a population of nearly three million people—that Bazalgette somehow had to work around.  “It was certainly a very troublesome job,” he would later write, with typical English understatement.  “We would something spend weeks in drawing out plans and then suddenly come across some railway or canal that upset everything, and we had to begin all over again.”  Pages 207-208

 

Bazalgette’s (above-ground) memorial

 

Yet somehow, the most advanced and elaborate sewage system in the entire world was operational by 1865.  The numbers behind the project were staggering.  In those six years, Bazalgette and his team had constructed eighty-two miles of sewers, using over 300 million bricks and nearly a million cubic yards of concrete.  The main intercepting sewers had cost only £4 million to construct, which would be roughly $250 million today.  (Of course, Bazalgette’s labor costs were much cheaper than today’s.)  It remains the backbone of London’s waste-management system to this day.  Tourists may marvel at Big Ben or the London Tower, but beneath their feet lies the most impressive engineering wonder of all.  Pages 207-208

 

Wonder of the world, this is

 

10. The planet of cities

 

Out of slums come cities. 

 

I’ve spent this whole multi-part post, all 10,000+ words of it, focusing on the Victorian slum, as if today’s London has no slums.  Of course it does, but to those from 1854, what today we call slums they would see as marvels of space, light, environment, and technology. 

 

Council housing, Hackney Wick

 

Those Victorians were urban pessimists:

 

If you time-traveled back to London of September 1854 and described to some typical Londoners the demographic future that awaited their descendents, no doubt many would react with horror at the prospect of  a “city planet,” as Stewart Brand like to cal it.  Nineteenth-century London was overgrown, cancerous monster doomed to implode sooner or later. 

 

That pessimism is exemplified in The Time Machine, by H. G. Wells (a modernist in his science, a Victorian in his morals if not his personal morality), where the future is ethereal vapid Eloi and Calibanian Morlocks

 

Young raffish Mr. Wells

 

Two million people crowded into a dense urban core was a kind of collective madness.  Why would anyone want to do the same with twenty million?  Pages 231-234

 

Off to a future of Morlocks and Eloi and devastation

 

Snow is the hero of Johnson’s story; Bazalgette the hero of mine.

 

[Concluded tomorrow in Part 6.]

 

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