Etruscan engineers built what would eventually become the Cloaca Maxima "greatest sewer" around BC. Originally conceived as an open canal to drain local marshlands, the system was converted gradually into an underground sewer running through the Forum and exiting at the Tiber.
Parts of it are still functional today. Named after the goddess of purification and powered by Rome's aqueducts, the Cloaca shuttled everything from street trash to public bath water to flows of excrement from the city's "rooms of easement. Cloaca, alas, was not well-served: Romans still dumped refuse into the streets, open troughs teemed with discharge from outhouses, and most everything unwanted wound up in a fetid Tiber.
Not until the mids did the link become clear between sewage and deadly waterborne diseases like cholera. It was at that time that the River Thames in London, which had ably dealt with human waste for centuries, reached its limits. It could no longer handle the output of a booming metropolis. The most tragic consequence: three major cholera outbreaks between and that claimed more than 30, lives and finally forced city leaders to act. Enter Joseph Bazalgette , one of the city's chief engineers, who in began a mammoth, decade-long project to build a network of sewers that ran parallel to the Thames, intercepting dirty surface water and underground waste and diverting it all downstream and out to sea.
Three massive pumping stations fed the sewer's 82 miles of new brick-constructed tunnels and pipes. Though the steam-powered pumps themselves were impressive, the system's simplest but most critical innovation was the V or egg shape of the main tunnels, which maximized water flow and supported more weight above them.
Some say Bazalgette's controversial choice of portland cement, which was costlier and much trickier to lay but much stronger than conventional alternatives, was just as important. With an eye toward the future, Bazalgette built the system to scale.
During the Neolithic era, also known as the New Stone Age from around 12, years ago to around 6, years ago, it appears that humans dug permanent wells for water use, however not much is known about sewage and its channels. These rooms appeared to be connected to an indoor, tree bark lined, stone fresh and wastewater system, moving liquids around the small area. During the Bronze and early Iron Ages, different parts of the world were doing a few different things.
In Ancient China, evidence of some of the earliest water wells by humans has been found as early as to years ago. The Indus Valley Civilisation in East Asia has quite a lot of early evidence in relation to sewage treatment. Most houses had their own private toilet, and sewage was disposed through underground drains built with carefully laid bricks.
They had a water management system that was very sophisticated for its time, with numerous reservoirs established and drains from homes were connected to wider public drains. In practice, water from the roof and upper storey bathrooms was carried through enclosed terracotta pipes or open chutes that emptied out onto the street drains.
A range of objects were used to collect human waste during this period, including outhouses, pail closets and cesspits. In China and Japan, they relied heavily on human waste as fertiliser, as cattle manure was not readily available. In most cases however, cities did not have an actual functioning sewer system before the industrial era approximately AD to - AD and relied on rain and nearby waterways to wash sewage off the streets.
In some locations, there were stepping stones to use to avoid the sewage that just flowed down the streets freely. After the adoption of gunpowder in European countries, municipal outhouses became an important source of raw material for the creation of saltpeter.
These connected to a large intercepting sewer, which transported the wastewater to the Chicago River, which was dredged to make room for the coming load. Ultimately, the city undertook another major engineering project, reversing the flow of the Chicago River so that, instead of discharging into Lake Michigan, it drew in water from the Great Lake and discharged it west into the Mississippi River watershed.
At first, sewers spread because cities would take on debt to pay for them, thanks to new financing mechanisms. This investment has been worth it in lives saved and public health costs averted, though new investments are now needed to maintain and sometimes replace these aging systems. And sewers never became truly universal in the United States. But these came without water and sewer connections, so people installed wells and septic tanks—technologies more appropriate for rural farm life, Melosi writes.
This gap has replicated itself on a global scale, as sanitary imperialism exported the sewer model ideal but not, among other things, the necessary financial mechanisms that allow cities to borrow the high up-front costs. Today, only about 62 percent of urban dwellers worldwide have access to sewers—a percentage that remained essentially flat between and —and those people are mostly in highand upper-middle-income countries, where coverage is still increasing.
In low-income countries, the sewer coverage dropped from about 24 percent to about 17 percent in the same period due to urban population growth. The world has been slow to admit it, but the sewer boom has ended, and it did so long ago. Excerpted from Pipe Dreams by Chelsea Wald. Copyright c by Chelsea Wald.
Created by Grove Atlantic and Electric Literature. Via Avid Reader Press. By Chelsea Wald. Chelsea Wald Chelsea Wald has repeatedly plunged into the topic of toilets since , when editors first approached her to write about the latent potential in our stagnating infrastructure.
Since then she has traveled to Italy, South Africa, Indonesia, and Haiti, as well as throughout the Netherlands and the United States, in search of the past and future of toilet systems. She has won several awards and reporting grants, including from the Society of Environmental Journalists, the European Geosciences Union, and the European Journalism Centre. She lives with her family in the Netherlands, in a region renowned for its water-related innovations.
Pipe Dreams is her first book. Close to the Lithub Daily Thank you for subscribing! Just Because You're Paranoid Danielle Evans on Mrs. November 12, by Caitlin Flynn.
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