Waste Not: A Brief History of the Urban Sewer System
Chelsea Wald on How We Get Rid of What We Don’t Want
My first night in Cap-Haïtien, Haiti’s sewer-less northern port city, I have just returned to my hotel from dinner when I hear a roar like a jet engine. Alarmed, I run to the window. It’s rain—torrents of it, arriving in thick waves to pummel the tin rooftops.
The next morning, I head out into a postdiluvian mess. The day’s main destination is Fort St. Michel, a poor neighborhood of 40,000 near the city’s airport. Like nearly half of the city, it is in a floodplain, and the narrow streets have become stagnant canals, with plastic bottles, tin cans, and rotting bananas floating in them. Families of small black pigs walk around, pissing into puddles. Barefoot children wade to school in their uniforms, holding their shoes so as not to dirty them. A gallant teenage boy carries a giggling girl on his back as the neighbors tease them.
With me in the rental SUV is Sasha Kramer, executive director of the nonprofit SOIL, which runs an unconventional sanitation business that serves this and other poor neighborhoods that otherwise rely on pit latrines or the uncertain privacy of dark corners and the spaces between cars. We’re following a plucky green-and-red vehicle, a three-wheeled motorcycle fitted with a flatbed on the back, which is making the rounds. It’s slow going: the motorcycle driver struggles to find a way through, inching forward and then backtracking when roads prove impassable. When he stops, his colleague, in a neon-green safety uniform with thick rubber gloves, wades up to his thighs in the waters, balancing stacks of tightly sealed green plastic pails in his arms. He places empty pails at doorways and on corners and picks up full ones left there for him. In those full pails? Poop.
Since Roman times, the ideal of sanitation infrastructure—indeed of all urban infrastructure—has been sewers. For some, they have epitomized civilization: Victorian thinker and philanthropist John Ruskin declared that “a good sewer was a far nobler and far holier thing . . . than the most admired Madonna ever printed.” More recently, the website Atlas Obscura dubbed the sewer “the most marvelous everyday invention” in its Mundane Madness competition. (Incidentally, the final four included the can opener, paper, and, in a related entry, toilet paper.)
Yet the smelly, lawless tunnels have just as often represented the dark side of cities. The ancient Roman Suetonius wrote that the Emperor Nero stabbed men on their way home from dinner and dropped their bodies into the sewers. Another ancient claimed that the emperor Elagabalus was murdered in a latrine and his assassins tried, unsuccessfully, to stuff him into a small sewer opening. Later literature would also use them in similar ways: Victor Hugo, a sewer aficionado, has good guy Jean Valjean escape through grimy Parisian sewers in Les Misérables, and Orson Welles’s bad guy Harry Lime does the same in the postwar Viennese sewers of The Third Man. More recently, the Teenage Mutant Ninja Turtles live in the sewer and the Super Mario Brothers (who are plumbers) have taken it as the setting of many battles with monsters. Sewers have been used for staging crimes, sheltering from air raids, and as command posts. “The history of men is reflected in the history of sewers,” wrote Hugo. “Crime, intelligence, social protest, liberty of conscience, thought, theft, all that human laws persecute or have persecuted, is hidden in that hole.”
The Romans began building sewers in the sixth century BCE, with the giant Cloaca Maxima (meaning “Great Sewer”), a wonder of nearly eleven-foot-high stone vaults. But this underground cathedral wasn’t meant to transport waste; rather, its function was to drain the marsh on which the city of Rome was built. Over the centuries, the Romans expanded the system throughout the city center, draining more land—for the Colosseum and the Circus Maximus—and controlling dangerous stormwater, as well as handling huge volumes of wastewater from installations like the Baths of Agrippa and the Pantheon, some of which would have included latrines. Today, many sections still transport wastewater and you can see the triple-arched outfall of the Cloaca Maxima along the Tiber River. The famous Bocca della Verità, a stone disk decorated with a face, was very likely originally an ancient manhole cover. Newlyweds stand in long lines to stick their hands in the open mouth as they pledge to be faithful to each other, since it’s said that it will bite anyone who lies to it. Koloski-Ostrow, the classical archaeologist, has investigated how well these sewers worked and found them lacking. For one, filth built up in the channels and still does, as she’s seen for herself, writing:
Once I tried to enter the sewer behind the Church of Santa Maria in Cosmedin and found the silt completely blocking the entrance. In another expedition in a sewer channel under the Roman forum (about 2007), I found myself repeatedly tripping over piles of debris and silt as I tried to maneuver my heavy boots along the slippery ledge through muddy waters still draining into the sewer from modern streets.
The Romans didn’t understand the physics behind their invention, so they couldn’t prevent this buildup through better design of the tunnels or junctions. Instead, slaves and convicts probably cleaned them out. There was another big difference between the Roman sewers and today’s: although some public latrines would have drained into them, most people didn’t connect their private toilets—perhaps because they didn’t want to. Looking at it from the Romans’ perspective, this makes sense. Toilets didn’t have any type of seal, so any connection to the sewer meant that substances could come up as well as go down. Among those: stench, floodwaters, and critters like rodents and insects. Decomposing organic matter in the sewers would have generated hydrogen sulfide and methane, and Koloski-Ostrow claims that explosions could have singed behinds. One ancient writer described a monstrous octopus that entered a merchant’s home through the toilet and ate pickled fish from his pantry.
It took almost 1500 years after the Roman era ended before a London lawyer named Edwin Chadwick helped create a vision for sewers as technologies especially for human waste, transforming the city’s underworld into what Hugo would describe (referring to Paris, which took a parallel path) as “clean, cold, straight, correct. It resembles a tradesman who has become a councillor of state.” In the early 19th century, sanitation was largely left up to individuals, and outhouses, often known as privies, prevailed. Then, as piped water connections increased and more people adopted water closets, wastewater began to overwhelm cesspools and storm drains.
Born in 1800, Chadwick believed in the environmental roots of disease, though people didn’t yet understand the mechanics of disease transmission at this time. To improve the environment of the city, Chadwick thought it would be necessary to replace the patchwork of water pipes and privies with a connected, comprehensive hydraulic system that would bring clean water into homes on one hand and then take dirty water out to sewers and ultimately to agricultural lands on the other. This blueprint for an “arterial-venous” city would, as Chadwick wrote, “complete the circle, and realize the Egyptian type of eternity by bringing as it were the serpent’s tail into the serpent’s mouth.”
Building such a system would be an engineering feat of enormous proportions. One challenge then, as now, was to design the sewer pipes to get an optimal flow of water. And so velocity became Chadwick’s “chief obsession,” Martin Melosi writes in The Sanitary City. On the one hand, the water must flow quickly enough to prevent suspended particles from settling at the bottom, which clogs the sewer. On the other hand, if the water flows too quickly, the suspended particles scour the interior of the sewer, potentially damaging it; a powerful flow can even blow out a weak structure. At first, Chadwick advocated shaping brick sewers like downward-pointing eggs. Later, he changed his allegiance to glazed earthenware pipes. But his plans tended toward the idealized and ignored on-the-ground realities of heavy rainfall, improper use (like flushed cloth and paper), and poor installation.
The British Parliament never bought into Chadwick’s all-encompassing, integrated, circular water and wastewater system, but it did fund a massive sewer network in the 1860s, after London experienced the Great Stink from the Thames. To build it they tapped Chadwick’s rival, engineer Joseph William Bazalgette, who disagreed with many of Chadwick’s preferences. Instead of transporting wastewater to agricultural lands, Bazalgette continued to dump sewage in the Thames, though he employed “intercepting sewers” to move these outfalls downriver. And he wasn’t a pipe purist: he used a combination of brick and earthenware. In the end, the groundbreaking network contained 83 miles of sewers, plus a few pumping stations to overcome gravity and tides, and served as a model for the world. Despite the failure of his most ambitious ideas, Chadwick could take a good deal of credit for this outcome, Melosi writes. “One of the key results was the transformation of Victorian cities from their Dickensian bleakness into more livable environments.”Sewers never became truly universal in the United States.
Other rapidly growing cities adopted the London model. In America, perhaps the most remarkable sewage works took place in Chicago. The city faced urgent problems: in 1854, a cholera epidemic felled roughly 1,400, or 1 in every 18, residents. Since the terrain was so flat, engineer Ellis S. Chesbrough suggested raising the city by as much as 12 feet in some areas, so that sewers could work by gravity. In 1858, some 200 jackscrews hoisted a giant brick building by more than 6 feet. In the following years, engineers raised a variety of other structures, including a luxury hotel, an ornate iron building, and half of a city block, with the stores on it still open during the procedure. Engineers elevating the streets laid sewer pipes, covered them with dirt, and then paved over them. 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.
Without any wastewater treatment, the sewage flowing into the river and out to Lake Michigan soon threatened the city’s drinking water. 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. This diversion, however, just passed Chicago’s filth to other cities downstream until it added wastewater treatment.
At first, sewers spread because cities would take on debt to pay for them, thanks to new financing mechanisms. In England and Wales, local authorities accumulated almost 100 million pounds of debt for waterworks and sewers by 1905—adjusting for inflation, that’s equivalent to about $16 billion today. Between 1860 and 1922, Melosi writes, American municipalities grew their debt from $200 million to more than $3 billion. 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.(A sewer pipe’s life span is about fifty to a hundred years, depending on the type of material and the conditions.)
And sewers never became truly universal in the United States. After World War II, a building boom created suburban homes for the millions of GIs returning home. But these came without water and sewer connections, so people installed wells and septic tanks—technologies more appropriate for rural farm life, Melosi writes. In the countryside, “a little odor or a soft spot in the middle of a field far from habitation was no cause for concern,” but “septic tanks when brought to town were a very poor choice on these small ‘postage stamp sized’ lots.” Many suburbanites now face the high cost of upgrading failing septic tanks, which contaminate groundwater with microbes and nutrients. Discharge from sewage and septic systems still contributes a substantial amount to nutrient pollution, which the US Environmental Protection Agency (EPA) calls “one of America’s most widespread, costly and challenging environmental problems.” In some places, such as northern Florida and Cape Cod, it’s the main source of that pollution.
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 2000 and 2017—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. Many cities are so dense and growing so quickly that it’s difficult to imagine undertaking the works necessary to install conventional underground sewers, which is why there’s such an urgent need for other options. 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. Excerpted with the permission of Avid Reader Press / Simon & Schuster. Copyright (c) 2021 by Chelsea Wald.