John Snow, 1813–1858
Snow was a fanatic about clean water. Soon after moving to London, he had already constructed a distillation apparatus in his lodgings so that he could boil and purify his water before drinking it. He had been fascinated by cholera epidemics for much of his career, and the miasmatic explanation struck him as inadequate. If cholera passed through the air, how to explain the fact that some members of a family would become ill while others did not, all living under the same roof and breathing the same air? How to explain that workers surrounded by the foulest of odors—“nightsoil handlers” and “flushermen” working with human waste—were not more susceptible to cholera than others? Snow suspected that cholera “poisons” passed through water contaminated with human waste and had published a pamphlet arguing this in 1849. He did not know how to demonstrate conclusively the disease’s cause, however, and the medical establishment’s confidence in the miasma theory remained unshaken.
The Soho deaths caught Snow’s attention, and he took advantage of the available data. In 1836, Parliament had passed the Registration Act, for the first time requiring personal records to be kept of the recently deceased, including the cause of death. Snow grew increasingly encouraged as he checked the records of the Soho cholera outbreak. He found that every cholera victim had lived within a quarter-mile of the popular Broad Street Pump, a fifteen-foot-deep well known for its clear drinking water. Snow’s theory, though, faced a major obstacle. A widow, Susannah Eley, had died of cholera during the outbreak but lived in Hampstead, nowhere near Soho; another woman had died in Islington, even farther away. If cholera had been transmitted through drinking water at the Broad Street Pump, how had it infected these women so many miles away?
Unwilling to discard his theory, Snow visited the widow’s son to see if there might be some unknown connection with the Broad Street Pump. As Snow heard the story of her death, he grew increasingly intrigued. While the widow had not visited Soho prior to her death, she had previously lived in the area. She so enjoyed the water from the Broad Street Pump that she regularly sent her servant to fill water bottles there. Indeed, she had done so days before her death. The son of the recently deceased widow went on to sadly relate that he had also recently lost a cousin. Had the cousin visited his mother? Snow eagerly inquired. Oh yes, the son replied. In fact, she had drunk the same Soho bottled water as his mother before returning to her home in Islington and dying the next day.
The famed “Ghost Map” from a report written by Snow in 1855 shows the incidences of cholera around the pump. Armed with this conclusive information, Snow persuaded the Soho Parish leaders to remove the pump handle at Broad Street, and the outbreak stopped soon after. This marked both the first time a government had sought to stop the outbreak of a waterborne disease and the birth of the modern field of epidemiology—the study of disease in populations. To honor Snow’s achievements, the International Epidemiology Association boasted a pump handle as its symbol (not to mention the pub, The John Snow, which is located right in front of where the pump used to stand).
John Snow’s map of cholera cases shows clustering around the Broad Street Pump
While rightly celebrated as real-life medical sleuthing that puts CSI and its innumerable spin-offs to shame, Snow’s detective work proved particularly persuasive to the Soho Parish leaders because it coincided with scientific developments playing out at the same time. While Antoni van Leeuwenhoek had seen and described the newly discovered world of microorganisms to the British Royal Society in the late 1600s, no connection had been made at the time between disease and these newest known additions to the living world. The hold of the miasmatic theory of disease was slowly loosening its grip through the nineteenth century, though, thanks to developments in the field of microbiology by Louis Pasteur, Robert Koch, Joseph Lister, and others.
The germ theory of disease was premised on two hypotheses: first, that specific diseases are caused by specific microorganisms that live in air and water, and second, that the same germs reproduce from bearers of the same disease, meaning that microorganisms and other life are not created by spontaneous generation. This was still highly controversial in Victorian England, however, and strong opposition arose to Snow’s explanation for the spread of cholera. The London Medical Gazette, a leading journal of the day, dismissed his arguments as “an entire failure of proof that the occurrence of any one case could be clearly and unambiguously assigned to the use of the water. … Foul effluvia from the state of the drains [i.e., an airborne miasma from the sewers] afford a more satisfactory explanation of the diffusion of the disease.”
Snow’s findings supported the germ theory, as did the later realization that the mother of an infant suffering from cholera had disposed of the child’s soiled diaper in a cesspit directly adjacent to the Broad Street Pump just days before the cholera outbreak. While the germ theory of disease remained controversial throughout the 1800s, its increasing credibility was crucial in shifting popular attitudes toward the prevalence of waterborne diseases.
The Soho Parish leaders were also well aware of the raging debate at the time over public sanitation. Championed by Edwin Chadwick, the Victorian crusade for improving the sanitary conditions of the urban poor centered on the idea that disease could be prevented. Trained as a lawyer, Chadwick was relentless, leading John Stuart Mill to praise him as the most effective politician of his time. Chadwick accepted the miasmatic theory of disease but opposed common wisdom by arguing that closer attention to drainage, clean drinking water, and removal of waste would greatly improve the well-being of the city’s poor.
In 1832, Chadwick was appointed as a member of the Royal Commission into the Operation of the Poor Laws and served as its secretary. The commission’s work led to reform in how aid was provided to the poor in Britain and resulted in a standing body, the Poor Law Commission, to oversee implementation of the new law. Chadwick served on the commission and used its platform to promote his agenda.
Edwin Chadwick, 1800–1890
In 1842, he set forth his views in the commission’s 457-page Report of the Sanitary Condition of the Labouring Population of Great Britain. In denouncing the state of affairs, Chadwick’s prose reads powerfully even today. Indeed, it was so incendiary that his fellow commission members refused to place their names on the report, leaving Chadwick as the sole author. In bold statements, he concluded that:
The various forms of epidemic, endemic, and other disease caused, or aggravated, or propagated chiefly amongst the labouring classes by atmospheric impurities produced by decomposing animal and vegetable substances, by damp and filth, and close and overcrowded dwellings prevail amongst the population in every part of the kingdom, whether dwelling in separate houses, in rural villages, in small towns, in the larger towns—as they have been found to prevail in the lowest districts of the metropolis.
Such disease, wherever its attacks are frequent, is always found in connexion with the physical circumstances above specified, and that where those circumstances are removed by drainage, proper cleansing, better ventilation, and other means of diminishing atmospheric impurity, the frequency and intensity of such disease is abated; and where the removal of the noxious agencies appears to be complete, such disease almost entirely disappears.
The formation of all habits of cleanliness is obstructed by defective supplies of water.
The population so exposed is less susceptible of moral influences, and the effects of education are more transient than with a healthy population.
These adverse circumstances tend to produce an adult population short-lived, improvident, reckless, and intemperate, and with habitual avidity for sensual gratifications.
The report was a sensation, its sale of ten thousand copies far exceeding sales of previous government publications. Beyond Chadwick’s clear indictment of dirty water and unsanitary surroundings as a prime cause of disease, it is worth taking a closer look at his prose, for Chadwick was concerned not only with the physical consequences of p
olluted water but the moral consequences, as well. Hence his warnings about those who drank defective supplies of water becoming “less susceptible of moral influences,” “reckless, and intemperate.” To Chadwick’s eyes, poor sanitation fostered immorality just as surely as it did physical disease.
Indeed, the direct connections Chadwick drew between sanitation and moral health are a significant part of the story. Chadwick’s and others’ calls for improved sanitation were reinforced by moral crusaders, evangelicals who sought to remedy society’s evils by physical as well as spiritual cleansing. The notion that “cleanliness is next to godliness” took root during this era, and made the religious community a powerful ally for sanitation reform. Chadwick and Charles Kingsley, another great reformer, often described sanitary reform as the “Will of God.”
The ranks of “sanitarians” swelled with the great and the good, including such luminaries of the age as Charles Dickens, Benjamin Disraeli, and Florence Nightingale. Their efforts, and those of their religious and morality allies, led to pioneering legislation such as the Sanitary Acts, Water Acts, and Public Health Acts, all of which laid the legal foundation for improved source protection. In a matter of decades, centuries-old habits were formally challenged and rejected.
The great wealth flowing from the four corners of the British Empire provided the means for major infrastructure projects. A firm believer in the miasmatic theory of disease, Chadwick contended that “all smell is disease.” The answer to the wastes creating the poisonous miasmas was, he argued, water flowing through sewers, which would wash away the sewage and, with it, the source of the city’s ills. This was a novel idea, long forgotten since the Romans. Prior to Chadwick’s time, sewers had been designed to drain rain from the streets; in fact, the term “sewage” did not even exist until 1849. It is interesting to note that John Snow and Edwin Chadwick, who agreed on most issues, strongly differed over the outflow of the sewers. Guided by the miasma theory of disease, Chadwick argued that the sewers should flow directly into the Thames. Snow, by contrast, realized that this would pollute the drinking water for many Londoners.
Improved sanitation and the provision of readily available safe drinking water both gradually became explicit government priorities, and the results proved impressive. In 1852, the average age of death in the English town of Dudley had been a shocking seventeen years old. Twenty years after sewers were constructed there, life expectancy had almost doubled. Similarly, from 1850 to 1900, life expectancy in French cities improved from thirty-two to forty-five years old. Medical advances clearly contributed to this increased longevity, but the Great Sanitation Awakening seems an apt title for such striking results.
London was not alone in these leaps forward. One could tell similar stories for Chicago, Philadelphia, or other cities. Similar to Edwin Chadwick, Noah Webster, author of the famed dictionary, urged his fellow Americans to recognize and improve the state of urban sanitation. Until this happened, he moralized, the poor “will still wallow in filth; croud their cities with low dirty houses and narrow streets; neglect the use of bathing and washing; and live like savages, devouring, in hot seasons, undue quantities of animal food at their tables, and reeling home after midnight debauches.” The Quakers of Philadelphia took the lead in this regard, mandating in 1794 that the streets be watered down for cleansing daily.
As described previously, New York’s strategy had focused on a massive engineering project to pipe water from the pristine Catskills-Delaware watershed, more than 120 miles northwest of the city, to a series of local reservoirs. Chicago’s efforts at source protection were even more heroic. The city had large sources of water but all were shockingly polluted, even by nineteenth-century standards. In 1860, the city of Chicago hired Ellis Sylvester Chesbrough, who was fresh from designing the water system for Boston. Chesbrough realized, as had Chadwick, that the key to source protection and clean water was removal of wastes. The problem, though, was that Chicago sat in a low swamp, and building a sewer under the city streets would not provide enough elevation for the waste to flow out of town. His solution was as novel as it was ambitious. Needing higher elevation for the waste to flow through the sewers, he laid the sewers on top of the streets, covered them, and then built new streets above the sewers, raising the buildings in the process, or turning their second stories into ground floors. The source for Chicago’s water supply was extended six hundred feet into Lake Michigan and then piped into the city.
Even more ambitiously, the city built the Chicago Sanitary and Ship Canal in 1900. This actually reversed the flow of the fetid Chicago River, sending it into the Mississippi rather than Lake Michigan, the city’s source of drinking water. The city’s incidence of typhoid fever did, in fact, go down, but the downstream city of St. Louis saw a rise in the disease as Chicago’s filth flowed by. The State of Missouri actually sued Illinois for public nuisance, and the case went all the way to the U.S. Supreme Court. Presaging the difficulty of demonstrating causation between pollution and specific illnesses that bedevils today’s toxic torts litigation, the Court held for Illinois. St. Louis had not shown a strong enough causal correlation between pollution in Chicago and deaths in St. Louis, three hundred miles down the Mississippi. There were too many potential intervening factors.
Impressive as these engineering feats were, it is important to ask why the same Awakening did not occur in other parts of the world at the same time, particularly in European colonial cities around the globe. This may seem an odd question. After all, the stringent water pollution laws and massive infrastructure in the developed world today stand in glaring contrast to the primitive source protection in much of the developing world. While it has become politically incorrect to use the terms “First World” and “Third World,” they have real meaning when discussing drinking water and source protection today.
What may be surprising, though, is that this sanitary divide is a recent distinction. When George Goodwin decried London as a “cesspool city” in the 1850s, he could very well have been saying the same thing for one of the jewels in England’s colonial crown, Madras in India. The stark contrast between London and Madras today, where less than a third of the Indian city’s population has adequate sanitation, is deceptive. If you had visited both cities a hundred fifty years ago, the similarities would have been more striking than the differences. As Peter Gleick has recounted, “most urban citizens—rich and poor—lived amidst excrement and sewage.”
In retrospect, there was a significant fork in the road roughly one hundred fifty years ago, with cities in the global north rapidly improving sanitation and drinking water quality, while those in the global south lagged behind. Indeed, the French term “cordon sanitaire” is used today to describe a barrier that prevents disease or other unwanted conditions from spreading. However, it originally referred to the “quarantine line” in colonial cities that quite literally demarcated separate sanitation systems—one for the Europeans and one for the natives.
Marshaling public and private investment for sanitation is a massive undertaking, so daunting that no city was able to create a comparable sewer system to Rome’s for almost two millennia. The decision not to invest in sophisticated sanitation infrastructure in colonies at the same time as the Awakening back in the imperial home countries was partly a result of fiscal priorities, partly a result of prejudice. Looking back, though, one thing is clear. Applying separate sanitation standards to the governing and the governed in the Age of Empire had far-reaching consequences for the human miseries from waterborne diseases that continue today.
With the emergence of the germ theory, understanding of the importance of improved sanitation, and acceptance that sanitation infrastructure was first and foremost a government responsibility, by the turn of the twentieth century, source protection had improved dramatically in Europe and North America. This is not to say, however, that drinking water diseases were a thing of the past. Far from it. Typhoid fever still claimed thousands of victims every year, including the fame
d aviation brother Wilbur Wright, who died in 1912. Indeed, it was just such concerns over drinking water that spurred the trips of wealthy Europeans to spas and the first boom in bottled water sales. Ensuring source protection was a limited solution. To take the next big step in ensuring the safety of drinking water, municipalities turned to an approach that had always been part of the drinking water story: treatment.
Water Treatment
The Old Testament’s Book of Kings recounts the story of the prophet Elisha, who followed Elijah. Soon after the death of his predecessor, Elisha traveled to Jericho. There, he was met by the men of the city, who sought his aid.
The men of the city said to Elisha, “Look, our lord, this town is well situated, as you can see, but the water is bad and the land is unproductive.”
“Bring me a new bowl,” he said, “and put salt in it.” So they brought it to him.
Then he went out to the spring and threw the salt into it, saying, “This is what the Lord says: ‘I have healed this water. Never again will it cause death or make the land unproductive.’” And the water has remained wholesome to this day, according to the word Elisha had spoken.
Once a water source has been identified and protected from pollution, it still may not be clean enough to drink, hence the need for water treatment. While the methods varied, and Elisha’s approach was surely unique, treatment of water was commonplace in the ancient world. Sanskrit writings from approximately 2000 BC recommend water purification methods.
In his classic tome written sixty years ago, The Quest for Pure Water, M. N. Baker exhaustively sets forth in more than five hundred pages “The History of Water Purification From the Earliest Records to the Twentieth Century.” While not a riveting pageturner, the book covers a truly impressive range of treatment technologies, from siphons in ancient Egypt and cloth straining in Persia to techniques of aeration, distillation, flocculation, coagulation, and William Walcot’s hopeful patent in 1675 for “making sea water fresh.” Interestingly, the most obvious purification method to us—boiling water—was not commonplace. While there are references to boiling water in the Middle Ages, the common practice was light boiling, which would have been only partly effective in purifying the water. Of course, if there is no conception of germs living in water, much less the health threat they might pose, then boiling water seems a waste of time.
Drinking Water Page 9