Image credit Wikipedia, John Snow
In 1854 there was a major outbreak of cholera in Soho, London. Nobody knew what caused cholera, but John Snow carefully mapped the location of every victim, (documented wonderfully in Stephen Johnson's book The Ghost Map) and figured out that the focus of the epidemic was a community pump. He removed the handle, forcing residents to get their water elsewhere, and the epidemic ended. It turned out that there was a leaky cesspit only a few feet away from the pump.
The authorities were not sure why, but did conclude that shit +drinking water = death. It didn't take long for the city fathers to take the easy way out: if you cannot rely on wells anymore, pipe in fresh water from afar. Why stop pollution of your water source when it is easier just to bring it from somewhere else?
This created a whole new set of problems. Abby Rockefeller wrote in Civilization & Sludge: Notes on the History of the Management of Human Excreta
"the system of cesspools and vault privies, which had been to some extent effective in avoiding pollution of waterways through their periodic cleanout by scavengers and the at least partial returning of human manure to farms, was overwhelmed by the pressure created by the new availability of running water."
People had more water than they knew what to do with, so they were dumping it into the gutters in the street, which would empty into the streams, which were getting pretty smelly so they started covering them over.
Having a ready supply of water led to some other technical developments; the toilet had been around since Elizabethan times but was pretty useless until there was a water supply. It didn't take long for people to figure out some fairly trivial technology to use even more of that very cheap water to just wash away their shit in toilets instead of paying someone to cart it away. And we have been doing it ever since.
Soon the covered gutters were replaced with enclosed sewers that poured all of this into the Thames, turning it into a disgusting sewer. In America, they watched this and looked for alternatives; Rockefeller notes that there was a real debate among engineers about what we should do with waste; some thought that it was too important for agriculture to throw it away. They advocated
"sewage farming," the practice of irrigating neighboring farms with municipal sewage. The second group, arguing that "running water purifies itself" (the more current slogan among sanitary engineers: "the solution to pollution is dilution"), argued for piping sewage into lakes, rivers, and oceans. In the United States, the engineers who argued for direct disposal into water had, by the turn of the 19th century, won this debate. By 1909, untold miles of rivers had been turned functionally into open sewers, and 25,000 miles of sewer pipes had been laid to take the sewage to those rivers."
And that how we ended up with the system we've got- cheap water washed the old system away, and has been washing away our waste ever since, an ad-hoc jury-rigged system of reaction to problems instead of actually planning ahead.
Next: The design of bathrooms, as ad-hoc and idiotic as the sewer system.
See previous entries:
The History of the Bathroom Part 1: Before the Flush