Water: The Epic Struggle for Wealth, Power, and Civilization - Steven Solomon (2010)

Part III. Water and the Making of the Modern Industrial Society

Chapter 10. The Sanitary Revolution

The summer of 1858 was one of the hottest and driest ever in London history. In the first fortnight in June, sweltering heat caused a putrid stench to rise from the pools of stagnant sewage that choked the river Thames—headlines in the British press dubbed it the Great Stink. Inside the Houses of Parliament overlooking the river, behind the heavy lime chloride-soaked window draperies, members who had dithered ineffectually for decades over the worsening unsanitary water and sewerage conditions suddenly discovered that they had no escape from the assault of the stench, which demanded their immediate response. Adding urgency to their concerns was trepidation that the miasmas emitted from the Thames were putting their own personal health in mortal danger, since the prevailing medical theory of the day held that diseases were communicated by such foul air. The Great Stink, in short, succeeded in riveting politicians’ attention in a way that all the many years of appalling manifestations of London’s mid-nineteenth-century sanitary crisis had not.

In the previous decade alone, two cholera epidemics had killed over 25,000 Londoners. Throughout the city, sewage and human waste regularly seeped from cesspools into wells and was flushed into the Thames from which it was promptly pumped back up in Londoners’ drinking water. People were consuming their own sewage. Yet even contaminated water supply was insufficient to slake the water famine among the city’s fast-growing population. Street taps that each supported 20 to 30 crowded houses often were opened to sell water only one hour per day three days per week. Not surprisingly, Londoners’ daily existence was afflicted with chronic illness, shortened lives, and infant mortality that claimed some 15 of every 100 children within their first year. Even the vociferous gathering cry to reform London’s water and sanitary system, echoed by such celebrated figures as author Charles Dickens and scientist Michael Faraday, had been insufficient to rally MPs to empower an effective central public municipal authority to meet the long-brewing crisis.

An environmental by-product of the urbanization that accompanied early industrialization, the Great Stink was more than a mere nuisance or embarrassing advertisement for the social virtues of the British Empire’s vaunted liberal market democracy. It threatened the very sustainability of a sufficiently healthy surplus force of wage labor to cheaply man the new factories. Given Parliament’s unresponsive record, when the weather suddenly cooled on June 17 to provide a break from the Great Stink, the Times of London bemoaned: “What a pity it is that the thermometer fell ten degrees yesterday. Parliament was all but compelled to legislate upon the great London nuisance by the force of sheer stench. The intense heat had driven our legislators from the portions of their buildings that overlook the river. A few members, indeed, bent upon investigating the matter to its very depth, ventured into the library, but they were instantaneously driven to retreat, each man with a handkerchief to his nose. We are heartily glad of it.”

Fortunately the Great Stink did not abate so quickly in the hot summer of 1858 as to dissipate from the politicians’ agenda. On July 15 House of Commons leader Benjamin Disraeli—the same Disraeli who two decades later as prime minister would boldly commit England to buying shares in the Suez Canal—took the floor and introduced the overdue mandate and funding legislation to purify the Thames’s water and construct a proper sanitary sewerage system befitting the world’s leading city. So it happened that after years and years of fruitless debate, the reform legislation passed in just eighteen days. It proved to be the watershed turning point of the mid-nineteenth-century Sanitary Awakening. The awakening triggered a public health and environmental revolution that in the twentieth century resulted in the virtual abolition of the age-old scourge of infant mortality, the breakthrough scientific germ theory of disease, a quantum jump in human longevity, an unprecedented explosion in urban and total global population, and an enlarged, proactive state role in the governing compact between democratic governments and free markets.

From the outset, industrial steam power and large manufactory production had promoted rapid urban concentration. Within a century, populations in factory towns like Manchester, Birmingham, Leeds, and Glasgow surged five- to tenfold. Great political metropolises like London and Paris also swelled. London made history by the turn of the nineteenth century by surpassing ancient Rome’s threshold of 1 million inhabitants, then tripled in the next sixty years to nearly 3 million. The swollen densities simply overwhelmed the urban sanitary and water supply infrastructures built for an earlier age. For nearly all of human history, cities had been unwholesome, disease-infested death traps reliant upon migration from the countryside to replenish the decreasing natural reproduction of their indigenous population. By the mid-nineteenth century, the historic urban challenge demanded an innovative response lest the Industrial Revolution and the liberal democratic institutions allied with it choked on the waste of their own astonishing growth.

Throughout history, water’s life-giving indispensability had always been double-edged. On the one side, drinking two to three quarts of clean freshwater daily sustained each person’s existence; several gallons enabled healthy cooking; about 10 to 20 gallons were needed for minimal hygiene. Yet simultaneously, drinking contaminated water and exposure to stagnant water bearing an infiltrating army of diseases also was the main source of human illness, abbreviated life spans, and physical miseries. The greatest waterborne killers of all ages were dysentery (a.k.a the bloody runs) and common diarrhea. Mankind’s transition from hunting and gathering to irrigated agricultural civilization had notably worsened average individual health and longevity by increasing man’s exposure to sitting pools in irrigation canals bearing malaria, yellow fever and dengue-transmitting mosquitoes, schistosomiasis, and guinea worm. Cities and intensifying industrialization elevated to prominence the deadly waterborne diseases that spread through unsanitary conditions, above all pandemics of cholera and typhoid fever.

Without understanding the science of waterborne disease, societies throughout time were cognizant of the linkage between water and illness. Almost everywhere consumption of freshwater was subject to precautionary social customs. Few drank it cold and untreated by choice, unless it came from a prescribed source. The fifth century BC Greek “father of medicine,” Hippocrates, who made civilization’s first systematic effort to associate disease and the environment, recommended boiling water to eliminate particles that darkened its clarity and polluted its taste. From ancient times the Chinese consumed hot tea and boiling water, which was widely sold on city streets by vendors. Chinese wise men believed that water possessed special qualities depending upon its origin: early spring rainwater was considered beneficial, water from storms was dangerous, water from melted winter frost or hailstones or obtained from cave stalactites was medicinal. In an admonition that accorded with both Hippocrates and modern science, any suspect water was to be boiled. Snow water in many parts of the world was a prized luxury shipped to royalty and coveted by those who could afford it for its curative powers. The ancient Romans likewise esteemed the drinking qualities of water from preferred springs, such as the source of the Aqua Marcia aqueduct that gained its natural purity and coldness by filtering through the porous limestone hills near suburban Tivoli. In medieval and modern times, Frenchmen appreciated pristine fossil water preserved for eons under high pressure in underground aquifers that jetted to the surface of its own accord when struck by a drill; such artesian wells took their name from their initial discovery in 1126 at Artois.

Tea, coffee, and chocolate, perhaps because they were consumed hot, were considered medicinal when they were first introduced to Europe from China, the Islamic Near East, and Mexico in the aftermath of the Voyages of Discovery. Around the same period, another disinfecting drink, alcohol distilled from grains, became popular. The Greeks and Romans had had primitive versions of distilled spirits in antiquity and stills were operating in the ninth century and thereafter in Europe. Modern distilled alcohol was recommended by doctors and apothecaries for its medicinal qualities; its popularization two centuries later was attended by a visible rise in public drunkenness. To help purify suspect water when better alternatives were unavailable a few drops of vinegar were sometimes added as a makeshift home remedy. Wine drinking, of course, had been popular in semiarid Mediterranean habitats from Greek and Roman times. Present-day Italians often mixed their wine and water. Hot sake, or rice wine, was long imbibed in Japan. The most ancient of all common ways of safely consuming one’s daily dose of purified water was beer. Beer drinking redounded to the health of ancient Babylonians, Egyptians, and Shang dynasty Chinese, and much later to northern Europeans. From the mid-nineteenth century, the urban rich often took the additional, expensive precaution of buying water that had been filtered of its crudest and largest foreign particulates.

Until the Sanitary Revolution, ancient Rome had represented history’s zenith in urban freshwater supply, hygiene, and sanitation. Public sanitary amenities had been known before Rome, but never on such a large scale and usually limited to enjoyment by the upper classes. The fifteen centuries after Rome’s fall, by contrast, were the regressive, sanitary dark ages. The conditions of public waterworks likewise heralded the fortunes of Rome’s successor cities. Byzantine Constantinople began its gradual descent from the sixth century AD in the same period that its attention shifted from building new water-storage dams, aqueducts, and giant cisterns to fortifying its existing supplies against the many sieges that followed. The city’s magnificent sixteenth-century Turkish Islamic revival was underpinned by an expansive burst of aqueduct-building and hydraulic renovations that followed the Ottoman conquest of 1453. Likewise, Roman civilization’s republican Italian descendant, Venice, was never able to grow to more than a fraction of Rome’s size in part due to its chronic scarcity of freshwater. Although it built elaborate rain catchments half-filled with fine sand to filter and decant captured precipitation, which dripped through into wells in the public square, Venice faced constant shortages during dry spells and when storms caused briny water to seep from the lagoon into the wells. As a result, a fleet of water boats ferried freshwater daily from the mainland.

Elsewhere in Europe, existing Roman infrastructure and hydraulic technology fell into desuetude. Christian Europe in the Dark and Middle Ages relied upon the most primitive water supply techniques, drawing water from local wells, springs, and rivers. Chamber pots were emptied straight out the window or into underground cesspools, whose foulness seeped out into city streets and water supplies. Conditions were worst in northern Europe, where the wet climate and lack of good drainage or sewage disposal systems all but guaranteed pollution seepage into drinking sources. Antipollution regulations existed, but were often ineffective. An eyewitness in late eighteenth-century Paris reported that the Seine, the city’s main drinking source, was particularly noxious the three times each week when dyers dumped their dye into one of its tributaries.

With the rapid urban growth of early industrialization conditions worsened. Heaps of rotting refuse, mixed with accumulations of human and animal excrement and urine, produced ungodly odors that overwhelmed olfactory sensibilities. “Whole quarters were sometimes without water even from local wells,” writes Lewis Mumford, historian of the city. “On occasion, the poor would go from house to house in the middle-class section, begging for water as they might beg for bread during a famine.” As freshwater became too precious for anything but drinking and cooking, personal hygiene deteriorated. Public bathhouses, which in the Roman tradition had remained popular into the fifteenth century, gradually degenerated into houses of prostitution and were closed by industrial times.

It was the new industrial towns of enlightenment Scotland and northern Britain that responded with the greatest alacrity to the sanitary and freshwater-supply challenges of the early nineteenth century. Scotland resurrected Rome’s public water supply ideals by impounding water behind dams and instituting the first modern water filtration systems. James Watt took a particular interest in Glasgow’s waterworks, which pumped water in a cast-iron pipe under the River Clyde with the assistance of six steam engines. Edinburgh tapped new springs and built a new dam and aqueduct so that by the mid-nineteenth century its six reservoirs provided each resident up to 30 gallons of wholesome springwater daily. Northern British industrial towns followed. By 1850 they had erected a dozen water supply dams to combat their shortages. Lagging far behind, however, was the world’s urban leviathan, London, all but paralyzed before a mounting sanitary crisis.

It was in the capital city at the very heart of the globe-straddling British Empire that urban living conditions grew so abominable that they provoked the Sanitary Awakening and public health revolution that eventually spread worldwide. Originally settled by the Romans, London had inherited a network of pipes that connected its public fountains and baths to one of the Thames’s tributaries. By medieval times water was being drawn from numerous wells, the Thames, and its tributaries, such as the Fleet and Walbrook, which today still course out of sight beneath London’s streets. Water was distributed to individual homes in buckets by an industry of private water carriers who by 1496 were indispensable enough to claim their own guild. Pipes of clay, lead, and hollowed-out elm trunks conveyed some water throughout London. Publicly drawn water was dispensed free of charge to householders, but business users such as brewers, cooks, and fishmongers were charged a plumbing maintenance fee. London’s first and only major long-distance water conveyance project, launched as a private venture, was initiated in 1613 to meet Elizabethan-era population growth. By 1723 there was enough water coming from the countryside for one of the half dozen private water companies to proudly fulfill its business pledge of providing water three times per week for three shillings a quarter. Because the Thames lay well below the elevations where it needed to be delivered in London, the proportion of water consumed from the Thames itself greatly increased with improved pumping technologies and soaring population. The first waterwheel pumps had been installed under London Bridge starting in 1582; steam pumps were used from 1726, one of the earliest applications of the newly minted Newcomen steam engine.

Yet neither waterwheel nor steam engine could overcome the perennial shortages of water quantity and deteriorating quality. The trebling of London’s population in the first sixty years of the nineteenth century outstripped the growth of available water supply. Simultaneously, the commensurate increase in dumped sewage turned the Thames into an increasingly toxic soup. The net effect was that pumping stations on the river were doing little more than recycling increasingly poisonously polluted water to an ever more desperately thirsty London populace. As early as 1827 an irate pamphleteer created a political stir by taking umbrage with the close proximity of water intake pumps to sewer outfalls. He described the state of the Thames as “charged with the contents of more than 130 public common sewers, the drainings from dung hill and laystalls, the refuse of hospitals, slaughter-houses, colour, lead, gas and soap works, drug mills and manufactories, and with all sorts of decomposed animal and vegetable substitutes.” In 1828, the Chelsea Waterworks Company introduced a pioneer filtration system to try to eliminate the largest foreign particulates; private water companies also later moved intake valves farther upstream away from the thickest pollution. Nevertheless, the rapidly dying fisherman’s trade testified that they were fighting a losing battle. The last salmon caught from the Thames was in 1833.

The strong tidal nature of the Thames magnified the unsanitary brew that created the Great Stink in 1858. The level of the Thames ebbed and swelled dramatically with the shifts between low and high tides. At highest tide, river water backed far up into the sewage drains under London’s streets, which were as much as 30 feet lower than the high tide mark. The sewage drained out as the tide receded, but before escaping was pushed partway back up again by the next rising tide. Thames sewage thus oscillated back and forth around London, turning pestilent with exposure, before gradually drifting out with the downriver current at lowest tides toward the sea.

Other deteriorating environmental conditions also converged in the Great Stink. For centuries Londoners disposed of their personal waste in cellar cesspools that frequently spilled over. On October 20, 1660, famous diarist of London life Samuel Pepys notated: “Going down to my cellar…I put my feet into a great heap of turds, by which I find that Mr. Turner’s house of office is full and comes into my cellar.” By 1810 London had an estimated 200,000 cesspools, one for every five residents. Some cesspools were emptied for a fee by nightsoil men, who sold the waste as fertilizer to countryside farmers. But the high cost of nightsoil removal—one-third a workman’s weekly wage—discouraged free-market forces from expanding this constructively sanitary practice. Schemes to improve London sanitation by commercializing nightsoil collapsed utterly in 1847 when guano, solidified South American bird droppings, became available to English farmers as a cheaper and more pleasantly applied fertilizer. Thus the volume of cesspool discharge, and the commensurate stench of London and the Thames, continued to grow.

Ironically, the crisis also worsened from the rise of one of sanitary history’s milestone achievements, the modern flush toilet, in the first half of the nineteenth century. The modern toilet originated with English poet and inventor John Harington, who in 1596 created it as a “necessary” for his godmother, Queen Elizabeth, whose high regard for cleanliness in an unsanitary age was reflected in her purported declaration that she bathed once a month “whether I need it or not.” Harington’s toilet had two of the three basic elements of the modern flush toilet—a valve at the bottom of the water tank and a system to wash down the waste. Yet Harington built only two toilets in his lifetime—one for his own home and one for Queen Elizabeth’s palace at Richmond. Two centuries passed without notable development until 1775 when Alexander Cummings, a watchmaker by trade, invented an improved version of Harington’s toilet. Successful commercialization began three years later when another self-taught inventor, Joseph Bramah, began selling toilets with an improved valve design; by 1797 he had sold over 6,000.

The third element of the modern toilet, a reliable flushing mechanism, is commonly associated with one of history’s subculture folk heroes, Thomas Crapper. Contrary to popular lore, Crapper did not invent the toilet and was never knighted. What Crapper did do was to obtain a patent for an effective flushing mechanism that fulfilled his toilet’s advertised promise of “a certain flush with every pull.” From 1861 to 1904, Crapper’s successful London plumbing business sold flush toilets with his name branded on them. His name captured the fancy of American soldiers returning from World War I, who immortalized Crapper in folklore by using it as a slang expression for the toilet, and possibly, in abbreviated form, as a verb to describe its purpose.

Toilet use in London became noticeable after 1810 and accelerated rapidly after 1830. Toilet flushing caused London’s water usage to surge—as much as doubling between 1850 and 1856 alone. The increased flow washed the waste from cesspools and sewers into the Thames, whose odor grew more putrid. At high tides, the waste backed up through the antiquated sewer lines into house basements.

The use of toilets directly connected to the sewer system, mandated by the government in 1848, had been championed by a growing sanitary reform movement that had arisen following the outbreak of London’s first cholera epidemic in 1831-1832. A leader of that movement was Edwin Chadwick, a lawyer and lifelong gadfly for social reform, whose influential Report on the Sanitary Condition of the Labouring Population of Great Britain(1842) had highlighted the link between unsanitary conditions and the disease-ridden and debased social conditions of the urban poor. To alleviate squalor, Chadwick advocated a completely new system of water and sewer pipes that would both provide abundant, clean freshwater and remove sewage far from human habitation. Aware that another disastrous cholera pandemic was headed toward England, Parliament in 1848 created a central board of health, with Chadwick at its head, to rebuild the nation’s sanitary infrastructure.

At the time, no one knew what caused cholera. The establishment view was that the disease was probably transmitted through foul smells; hence Chadwick’s rationale for flushing the malodorous waste away from underneath residential streets to the river. Florence Nightingale, who gained fame nursing those afflicted during the terrible cholera epidemics of the era, was a firm believer to the end of her life in the prevailing miasmatic theory of disease.

In hindsight Chadwick’s sanitary policy prescription was farsighted. But its sequencing of flushing the sewers into the Thames as the first step before providing clean-drinking-water pipes proved to be tragically misguided in the devastating cholera epidemic of 1848-1849 because it misconstrued the nature of cholera. Chadwick’s sequencing was challenged, unpersuasively to decision makers, by an inspired young London anesthesiologist named Dr. John Snow, who advanced the prescient theory that cholera was transmitted through contaminated water. Flushing the sewers into the Thames increased the mix of feces and drinking water, and thereby, he maintained, spread the epidemic, rather than helped contain it.

Cholera was the first rapidly spreading global disease and the most feared of the nineteenth century. A victim contracting the bacteria in the morning could be dead of its horrifying symptoms from acute dehydration by nightfall. Sudden stomach cramps, intense diarrhea, vomiting, and fever declared the disease. The face grew haggard and sunken and the skin became black and blue from rupturing capillaries. Death came from collapse of the blood circulatory system. Often one-fifth to half of those contracting the disease died.

Cholera emerged in 1817 from the delta of the Ganges River near Calcutta. It spread rapidly around the world in half a dozen pandemics, some of which leapfrogged continents as fast as a steamship could travel. It voyaged in contaminated drinking water casks aboard ship and in the fecal secretions of its victims. It spread readily between the leaky sewers and wells and in the foul drinking, cooking, and bathing water pumped up from polluted rivers like the Thames. Soldiers carried it into battle and spread it as they marched. Cholera usually showed up first in port cities, spreading rapidly along rivers, canals, and commercial routes.

The first pandemic spread in Asia, but did not reach Europe. The second emerged in 1826 from Bengal and became truly global. It struck Moscow in 1830, killed 100,000 in Hungary in 1831, hit the Baltic by 1831, and jumped by ship to England. Cholera doomed thousands in London and Paris in 1831-1832. Quarantines failed to do anything but add to the material deprivation of the cramped urban poor, who were the most afflicted due to the abysmal state of their hygiene. Riots broke out in Paris. Doctors were stoned by half-crazed mobs. In London they were accused of murdering victims in order to dissect their corpses. By 1832 the pandemic reached Ireland, then crossed the Atlantic with emigrants to terrorize Montreal and Quebec. It migrated south to the United States, striking Detroit and towns along the Erie Canal. New York became a graveyard of tolling church bells and citizens fleeing for the pastures of northern Manhattan. By 1833 the cholera reached Mexico. Pilgrims on the hajj to Mecca, first struck in 1831, carried the disease back to Islam’s far-flung global homelands. Some 13 percent of Cairo’s inhabitants were decimated.

The cholera pandemics that ravaged London in 1848-1849 and again in 1853-1854 added fervor to the debate over the disease’s cause. In a celebrated case of medical sleuthing, John Snow, determined to find hard evidence to back up his waterborne theory of cholera, tracked a disproportionate number of cholera cases in the latter outbreak to a single free public well pump at Broad Street, not far from his own Soho medical office, that was widely used by the neighborhood’s overcrowded, poor residents. Subsequent research revealed the proximity of the well to a potentially contaminating sewer. Snow persuaded a local governing body to remove the pump handle to prevent further contagion. But he could not persuade the special government committee investigating the cholera epidemic, who saw potential miasmatic causes as well. Snow continued to press his pioneering work to the end of his short lifetime. He died prematurely in 1858, the year of the Great Stink, at age forty-five.

Parliament’s political will for sanitary reform had oscillated with the outbreaks of cholera. Yet even the tens of thousands of cholera deaths within five years during the midcentury epidemics did not provide enough impetus to overcome the entrenched nexus of vested local interests and liberal market economic ideology of those opposed to any centralization and enlarged public role for London’s fragmented municipal government. The increasing foulness of the Thames and fear of the next pandemic, however, was a constant reminder that reform’s opponents could offer no viable remedy of their own.

The mid-nineteenth-century sanitary crisis was an early manifestation of an inherent dilemma in the industrial market economy: it had no automatic, internal mechanism to restore a healthy equilibrium to natural ecosystems polluted by the unwanted by-products of growth, even though such environmental sustainability was a necessary condition of its continued productive expansion. In ancient Rome the sanitary welfare and public order had been provided by state bread doles and the public construction of aqueducts. In England the liberal democratic competition among pluralistic interests, under the duress of urgent crisis, ultimately produced an accountable municipal body with sufficient authority to provide for the common public good. The final triggering event for this reform was the Great Stink, which Parliamentarians, led by Disraeli, personally could no longer ignore.

Once empowered, London’s Metropolitan Board of Works expeditiously built a world-class model urban sanitary and water supply system. Under the direction of its longtime chief engineer, Joseph Bazalgette, a sophisticated network of intercepting sewers was built under London, part of which ran parallel along each side of the Thames, to reroute the waste far downriver from central London. At certain low-lying areas the sewage had to be lifted to join the gravity flow of the rest of the system. To house part of the network, as well as provide for the underground railway, gas lines, and other familiar modernizing features of late Victorian London, three river embankments were constructed between 1869 and 1874. Another innovation was to build the sewers and tunnels with little-tested Portland cement, which proved both admirably resistant when submerged in water and able to withstand three times more pressure than traditional Roman cement.

Validation for the new sewerage system came swiftly. In the cholera pandemic of 1866, the only afflicted communities in London were those not yet fully connected to the new network. London was never again afflicted with cholera. The 1866 experience tilted the tide of official opinion in favor of Snow’s hypothesis that cholera was indeed communicated through contaminated water. Final doubters were quelled by the dramatic 1892 experience in the German city of Hamburg, where one side of the street, which drew its water unfiltered from the Elbe, was devastated by the cholera outbreak while residents on the other side of the street, who drank filtered water, were entirely spared. By then, German scientist Robert Koch had already announced his 1883 discovery of the waterborne cholera bacillus during an outbreak in Egypt.

Koch’s isolation of the cholera bacillus, buttressed by the contemporary research of Louis Pasteur and other pioneer bacteriologists, was a cornerstone of the landmark germ theory of disease and the stupendous public health breakthroughs of the twentieth century. Koch won the Nobel Prize in 1905. By 1893 a cholera vaccine had been developed and inoculations quickly became commonplace. The cholera breakthrough was rapidly replicated with cures for other major bacterial diseases. Typhoid fever—another waterborne filth disease whose epidemics afflicted urbanizing cities throughout the nineteenth century, and in 1861 claimed the life of Queen Victoria’s husband, Prince Consort Albert, and later nearly killed her son and future king Edward—was brought under control with an effective vaccine (1897) and the same sanitary reforms that eradicated cholera. Following the stunning success of U.S. doctors in eradicating endemic, mosquito-borne yellow fever during the construction of the Panama Canal, a worldwide assault on the disease was launched in 1915 by the newly created Rockefeller Foundation; by 1937 a new, inexpensive vaccine all but eliminated the dreaded disease as a world health problem. Global malaria control became a target in the 1920s. Initial success came with drainage, and after World War II the widespread use of pesticides, such as DDT. All in all, the virtual elimination of many communicable diseases through the combination of improved sanitary and environmental conditions, antibiotics, and vaccinations caused average human longevity to leap stunningly by twenty years between 1920 and 1990 and doubling from the pre-Sanitary Awakening age. Infant mortality plunged, falling to half of 1 percent in the United Kingdom and most of the industrialized world by the early twenty-first century—a twentyfold improvement from the mid-nineteenth century.

The Sanitary Awakening and acceptance of the germ theory of disease also spurred England to take important further actions to ensure that London’s water supply was both ample and clean. The guiding principles were that water should be drawn from the cleanest available source, purified, and protected against contamination during distribution. Although the Thames remained London’s main supply of drinking water, it was supplemented by underground and upland river sources. Filtration plants were built to eliminate impurities through various methods, including traditional, slow sand filtering and, after the 1890s, rapid filtration of water pretreated with coagulants. Another key turning point was achieved with chlorination of water supplies from the early twentieth century. To purify water of germs, other chemical and heat disinfectants were applied, including copper, silver, ultraviolet light, and powerful ozonization processes. Sewage was jettisoned far from population centers into bodies of water under the catchy, good housekeeping guideline of societies everywhere that “the solution to pollution is dilution.” From the late nineteenth century, London ceased discharging its sewage into the Thames and instead carried it on barges to be dumped in the ocean.

By 1900, England had turned the corner on improving public sanitation and health. Very gradually, the Thames recovered. Even the fussy salmon reappeared in the river in 1974 after a 140-year hiatus. By 2007, London had some 14,000 miles of sewers and was preparing its first major upgrade, featuring a 20-mile-long sewage storage tunnel under the river, since the original Victorian-age network because the old sewer system could no longer handle a population that had grown to 8 million.

England’s sanitary revolution triggered a virtuous cycle of competition among industrialized democracies to improve water supplies and public health. By 1920, residents of almost all the world’s rich industrial cities in Europe and North America enjoyed abundant, clean freshwater for drinking, cooking, and washing. For the first time in 5,000 years, cities became generally self-sustaining habitats for human populations. Typhoid and yellow fever outbreaks, and some cases of great, deadly fires, induced several eastern American cities to act contemporaneously with Scotland and northern Britain to provide water for sanitation, drinking, and firefighting. By 1860, 12 of the largest 16 American cities had municipality-run water supply systems. At the turn of the twentieth century, Chicago achieved America’s most ambitious civil engineering project until the Panama Canal—the reversal of the flow of the Chicago River. By reversing its flow, the river no longer evacuated sewage into the city’s Lake Michigan drinking supply, but instead carried it downstream to be diluted in the Illinois and Mississippi rivers. Death from waterborne disease fell sharply in America and became negligible by 1940.

Contemporaneously, sewage treatment plants became commonplace. In one of the unsung achievements of modern society the effluent of fully treated wastewater was often wholesome enough to be safely consumable as drinking water, although almost nowhere in the world did cities dare to actually do so. After the three steps of state-of-the-art sewage treatment—filtering our solids, breaking down the remaining organic matter with microorganisms, and applying chemical disinfectants to kill remaining bacteria—the quality of the discharged water was often superior to the bodies of water into which it was discharged. Rather than being dumped in the sea, London’s sludge today is incinerated through a bed of sand at 850ºC—with the recovered heat used to power electricity-producing steam turbines that drive the treatment plant, and the excess energy sold to Britain’s electric grid. The final, released wastewater is measurably cleaner than the water in the Thames.

By enormously increasing the supply of clean freshwater resources, the sanitary revolution played a pivotal role in sustaining the urban ecosystems at the heart of industrial civilization. Without it, the momentous, rapid shift of humanity from the farming countryside to the industrial cities would have been impossible. In 1800, only 2.5 percent of the world’s population, or about 25 million people, lived in cities. In 2000, nearly half the world’s 6 billion people did so. Urban concentrations became immense: 29 megacities held over 7 million compared to only six cities in the world with 500,000 two centuries earlier.

Western liberal democracies’ success in delivering ample freshwater and sanitary services to its citizens provided one of its important comparative economic and politically legitimizing advantages over its Cold War rivals. The communist world’s authoritarian, command economy states, in contrast, lagged notoriously far behind in providing sanitary and other kinds of environmental health—both a leading indicator and a causal force of their relative decline. Shortly before the collapse of the Soviet Union in the late 1980s, for example, the Moscow River received untreated nearly all the sewage of the capital city, rendering it virtually an open sewer reminiscent of the Thames during the Great Stink. In the same period, some 90 percent of Chinese cities had no wastewater treatment at all. Worse still were conditions in the third world, which could best be compared to those of Europe in the mid-nineteenth century, with 90 percent of all sewage and 70 percent of industrial wastes dumped into streams and lakes without any treatment at all at the dawn of the twenty-first century.

That the influential pacesetter in leading the response to the sanitary environmental challenges of early industrialism had shifted from Britain to the United States was not coincidental. It reflected the continuing historical shift westward in power across the oceans to the United States, which became the world’s most prolific, productive, and innovative manipulator of water by the early twentieth century.