On the morning of August 8, three inches of rain fell on Brooklyn. On the 3,200 Brooklyn acres that drain into the Red Hook Water Pollution Control Plant, 260 million gallons of runoff coursed into the sewers, mixing with millions of gallons of human waste already headed towards a treatment plant capable of processing only 60 million gallons per day.

When flow exceeds capacity by that much, the only choice is to channel it all, untreated, into the waterways. And so emergency outflow points in Brooklyn’s Gowanus Canal and across Upper New York Bay began to ejaculate diluted sewage.

But aside from homeowners whose basements were flooded by Gowanus sewage and beachgoers who swam in feces the next day, few people paid attention to the sewer overflows. After all, New York City averages 53 combined sewer overflows (CSOs) a year, and 772 American communities have combined wastewater and rainwater sewers that overflow during heavy rains. But since CSOs rarely make the news and few politicians want to stake political capital on sewers, the political will to fix them probably won’t appear until the problem becomes a catastrophe.

This is the story of one such catastrophe: a stench so vile that it changed the course of human sanitation.

London in 1858 was not a pleasant place for people who enjoyed breathing through their nose. The Industrial Revolution had attracted three million fortune-seekers to the big city, turning housing into a two-pronged competition: landlords tried to see how many times they could subdivide a flat and tenants tried to see how many people they could pack into each one. Every inch of real estate not reserved for someone sleeping was appropriated by the machinery of capitalism — neighborhoods teemed with tanneries, breweries, soap factories, glue works, slaughterhouses, laundries, and bone boilers, and pollution spewed into the skies and streets and sewers from each one.

Spewing waste: that’s an excellent metaphor for London in 1858. Waste spewed from buildings and waste spewed from the people. And it was this inexorable brown flow that, in the summer of 1858, brought the city to its knees.

As described in Poop Culture, the flush toilet had by 1858 become a social necessity. The elite Victorians’ late 18th Century embrace of the apparatus had trickled down to their social inferiors; mid-19th Century bourgeoisie agreed that anything flushless was uncivilized. But until 1847, law and custom both held that sewers were for drainage and not for human waste — anything bearing urine or feces was legally and morally obliged to be emptied only in the nearest cesspool. So the majority of flush toilets were plumbed to outflow not into sewers, but into pits in people’s backyards.

Cesspools could contain the quantity of waste deposited via chamber pots and privies, but the gallons of water accompanying every flush of the toilet proved too much to bear. As more and more toilets were installed in the city, more and more cesspools began to overflow. Liquid sewage would leach into basements and drinking wells until reaching the nearest sewer — which, designed for drainage, would channel the muck into the nearest waterway. And so as the summer of 1858 began, the biological and commercial feculence of London was flushed in ever-increasing volumes into the Thames.

June of 1858 was dry. Damned dry. So dry that the current of the Thames slowed almost to a stop.

June of 1858 was hot. Damned hot. So hot that the biological stew floating atop the still waters of the Thames began to putrefy.

And so began the Great Stink.

“A Stygian pool reeking with ineffable and unbearable horror,” Prime Minister described it. Human and animal feces, dead dogs and cats, entrails from the slaughterhouses, rotten food, and the mechanized vomit of countless factories bobbed and bubbled while the people of London invested heavily in scented handkerchiefs. But as bad as it must have stunk, smell is something people can get used to. (And it’s not like previous summers had been remembered for smelling of roses. Michael Faraday’s 1855 description of the Thames: “The whole of the river was an opaque pale brown fluid.”) No, the stench of the Thames terrified London because most Londoners genuinely believed the odor would kill them.

In 1858, both science and laymen alike subscribed to the miasma theory of disease: that cholera, malaria, and the common cold were all caused by inhaling air infected through exposure to putrefying matter. Although Dr. John Snow had demonstrated in 1854 that cholera was caused not by miasma but by fecal contamination of water, his theories had few believers at the time of his death on June 16, 1858 — right at the height of the Great Stink. So while John Snow was being laid to rest at Brompton Cemetery, Londoners feared for their lives of the smells arising from the Thames’ clotted waters.

With Parliament right on the banks of the river, the politicians’ first act was, of course, to save themselves: they ordered curtains soaked in chloride of lime to be hung in the windows. Presumably the smell of the chemical overpowered the smell of the river and thus, by their science, neutralized whatever foul demons rode the invisible airwaves of odor. For a brief time, Parliament smelled less like putrefying shit and more like the 1858 equivalent of Formula 409, and the business of running the country continued.

But when the stench proved too resilient, Parliament realized more needed to be done to ensure their own well-being. Welsh MP Owen Stanley repeated to the great body Dr. John Bredall’s testimony at the Court of the Queen’s Bench: “It would be dangerous to the lives of the jurymen, counsel, and witnesses to remain. It would produce malaria and perhaps typhus fever.”

So, for the good of the nation, Parliament abandoned the portions of the building overlooking the river.

Well-to-do Londoners fled for the summer retreats. But working-class London stayed put, holding their breath, avoiding the river, and hoping not to die as the stench smothered the city (and, according to one source, spawned an epidemic of giant flies). A few brave sanitary engineers attempted to solve the problem by dumping tons of chemicals into the Thames. Chloride of lime, chalk lime, slaked lime, and carbolic acid went in by the ton, but whatever effects these chemicals may have had were negated by the ceaseless sludge spewing from the buildings and the people. While the Great Stink was created by man, only nature could end it.

Fortunately for London, nature intervened: after a fortnight of misery and terror, the heat finally broke and the rain finally came. The Thames began to flow. The stink began to dissipate. And the politicians began to do their jobs.

Just like our government today is well aware of the problems of combined sewers, so too were London officials fully cognizant of their sewer problems in the years before the Great Stink. By 1847, sanitation had gotten so bad that a consolidated Metropolitan Commission of Sewers was formed to begin surveying and mapping the existing problem. (From an 1849 report: “The smell was of the most horrible description, the air being so foul that explosions and choke damp were frequent. We were very nearly losing a whole party by choke damp, the last man being dragged out on his back through two feet of black fetid deposit in a state of insensibility.”) In the eleven years prior to the Great Stink, six separate commissions evaluated 137 proposed solutions without making any tangible progress.

But in the weeks immediately following the Great Stink, Parliament rapidly authorized three million pounds for the Metropolitan Board of Works’ famed engineer Joseph Bazalgette to build a massive sewer system. Bazalgette then spent the next seven years building 82 miles of intercepting sewers, 250 miles of main sewers, and 13,000 miles of local sewers to channel London’s entire sewage output downstream to Barking and Crossness, where it could be released into the Thames, untreated, during periods of favorable current — sparing London the dangers of miasmatic sewage, but leaving the question of treatment for a future generation.

Bazalgette’s sewers, which became a model for combined sewers in New York City and across the west, experienced their first major overflow event on July 26, 1867, when 3.25 inches of rain fell on London. As per Bazalgette’s design, emergency outflow points opened and diluted sewage and water spewed directly into the Thames.

140 years later, on October 11, 2007, 1.48 inches of rain fell on New York City, and the exact same thing happened. On the 3,200 Brooklyn acres that drain into the Red Hook Water Pollution Control Plant, 128 million gallons of runoff coursed into the sewers, mixing with millions of gallons of human waste already headed towards a treatment plant capable of processing just 60 million gallons per day. Emergency outflow points across the Gowanus Canal and Upper New York Bay opened up, and diluted sewage once again spewed into the water.

In London, CSOs spew 5.2 billion gallons of sewage into the Thames each year; New York City’s waterways choke on 27 billion gallons of sewage for the same reason. In both cities, and in 772 communities across America, the problem is known but not considered urgent. London’s CSOs will cost £2 billion to fix; America is looking at $4 billion for New England’s problems alone. But with no movement towards resolution, the sewage will just continue to spill until another catastrophe finally occurs.