We Live Like Royalty and Don’t Know It
Introducing “How the System Works,” a series on the hidden mechanisms that support modern life
Johnny Appleseed used to be a staple character in old American children’s books. A ragged vagabond in the early nineteenth century, Appleseed traveled barefoot through the forest, wore coffee sacks with cut-out holes for his arms and head, and planted thousands upon thousands of apple trees for the first settlers in Pennsylvania, Ohio, Illinois, and Indiana.
“Appleseed” was a nickname; he was born as John Chapman. As a young man, Chapman became convinced that Christianity had lost its way and needed to be restored by a new church. He worked in an orchard, fell in love with apples, and devoted the rest of his long life to wandering through the newly occupied Middle West, passing out tracts for the new church — and establishing apple orchards, selling the saplings for a few pennies each.
Although a dozen or so Johnny Appleseed festivals are still celebrated, he is less likely to be found in children’s books today. That may be because historians realized that Appleseed was not just a kindly religious eccentric who went around planting apples so that Midwesterners could have fresh, healthy fruit. Instead, he was a vital part of village infrastructure: his apples were mostly not for eating, they were for making hard cider.
Typical hard cider has an alcohol level of about five percent, enough to kill most bacteria and viruses. Many settlers drank it whenever possible, because the water around them was polluted — sometimes by their own excrement, more commonly by excrement from their farm animals. Cider from Appleseed’s apples let people avoid smelly, foul-tasting water. It was a public health measure — one that, to be sure, let some of its users pass the day in a mild alcoholic haze.
For as long as our species has lived in settled communities, we have struggled to provide ourselves with water. If modern agriculture, the subject of the previous article in this series, is a story of innovation and progress, the water supply has all too often been the opposite: a tale of stagnation and apathy. Even today, about two billion people, most of them in poor, rural areas, do not have a reliable supply of clean water — potable water, in the jargon of water engineers. Bad water leads to the death every year of about a million people. In terms of its immediate impact on human lives, water is the world’s biggest environmental problem and its worst public health problem — as it has been for centuries.
On top of that, fresh water is surprisingly scarce. A globe shows blue water covering our world. But that picture is misleading: 97.5 percent of the Earth’s water is salt water — corrosive, even toxic. The remaining 2.5 percent is fresh, but the great bulk of that is unreachable, either because it is locked into the polar ice caps, or because it is diffused in porous rock deep beneath the surface. If we could somehow collect the total world supply of rivers, lakes, and other fresh surface water in a single place — all the water that is easily available for the eight billion men, women, and children on Earth — it would form a sphere just 35 miles in diameter. Adding in reachable groundwater would add some miles to that sphere, but not enough to dramatically alter the fact that our water-covered globe just doesn’t have that much fresh water we can readily get our hands on.
Couldn’t we make more? It is true that salt water can be converted into fresh water. Desalination, as the technique is called, most commonly involves forcing water through extremely fine membranes that block salt molecules but let water molecules, which are smaller, pass through. The Western hemisphere’s biggest desalination plant, in Carlsbad, California, is a technological marvel, pumping out about 50 million gallons of fresh water every day, about 10 percent of the water supply for nearby San Diego. But it also cost about $1 billion to build, uses as much energy as a small town, and dumps 50 million gallons per day of leftover brine, which has attracted numerous lawsuits. For now, in most places, supplying fresh water will have to be done the way it has always been done: digging a well or finding a river, lake, or spring, then pumping or channeling the water where needed.
No matter what its source, almost every way that humans use water makes it unfit for later use. Whether passed through an apartment dishwasher or a factory cooling system, a city toilet or a rural irrigation system, the result is an undrinkable, sometimes hazardous fluid that must be cleaned and recycled. When water engineers say, “We need clean water,” clean is the part they worry about.
Clean water is a necessity for more than just drinking. Almost three-quarters of human water use today is for agriculture, especially irrigation (out of all the world’s food, about 40 percent is grown on irrigated land). Another fifth of water use is by industry, where water is both a vital raw ingredient and a cleaning and cooling agent. Households are responsible for just one-tenth of global water consumption, but most of that is used for cleaning: washing dishes, washing clothes, washing people, washing away excrement.
Providing the clean water needed for all these purposes entails four basic functions:
Simple to describe, these tasks are hair-pullingly complex on the ground. The challenge of building and operating a water system that can supply the daily onslaught of morning flushes and showers while not flooding people who turn on their taps at low-use times is the sort of thing that keeps engineers awake at night. Even simple water-supply pipes are more complex than one might think. Water is heavy and not very compressible. When it travels through a pipe, it can acquire a lot of momentum. When multiple water users close valves or stop pumps, the momentum can create a shockwave in the pipe. In big pipelines, this “water hammer” is like a freight train smashing into a wall — it can damage the pipeline or tear apart equipment. Special slow-closing valves and pumps are required.
Difficult as these technical issues are, they have been largely understood since biblical times and before. By far the biggest and most frustrating obstacle is instead what social scientists call “governmentality” — and what everybody else calls corruption, inefficiency, incompetence, and indifference.
The evidence is global and overwhelming. English cities lose a fifth of their water supply to leaks; Pennsylvania’s cities lose almost a quarter; cities in Brazil lose more than a third. So much of India’s urban water is contaminated that the cost of dealing with the resultant diarrhea is fully 2 percent of the nation’s gross domestic product. Texas loses so much water that just fixing the leaks could provide enough water for all of its major cities’ needs in the near future. All fifty states and all U.S. territories are plagued by water systems with lead pipes, which can leak dangerous lead into their water. The Mountain Aquifer between Israel and Palestine is the primary source of groundwater for both. In an atypical act of collaboration, both are overusing and polluting it. And so on.
Water systems and their problems are as old as the first cities, and possibly older. The urban complex of Mohenjo-Daro, on the banks of Pakistan’s Indus River, arose about 2600 b.c., around the time that Egyptians were erecting the pyramids. Mohenjo-Daro was the biggest city in what archaeologists call the Harappan or Indus Valley civilization. Most of the citizenry lived in the “lower town,” a Manhattan-like grid of streets and boulevards faced by low brick buildings. Atop a high platform of mud bricks to its west was the “upper town,” sometimes romantically called the Citadel, a civic center that held relatively few people. Remarkably, there is little evidence that people in the upper town were richer or more powerful than those in the lower — Mohenjo-Daro seems to have been a surprisingly egalitarian place.
Water control was at its heart. Some 700 public wells dotted the lower city, many of them sixty feet deep. Cylindrical and lined with bricks and plaster, these wells created an urban water supply with a capacity and safety level that would not be matched until the modern era. Its source was snowfall and rainfall in the foothills of the Himalayas that had percolated into the soil, becoming groundwater; during its journey from the heights to the ground beneath Mohenjo-Daro, the water passed through layers of rock and sand that filtered out contaminants.
Mohenjo-Daro had an equally impressive system for flushing dirty water out of the city. Beneath both upper and lower cities was an intricate arrangement of drains, most of them narrow trenches in the streets, usually about two feet deep and covered by bricks that could be removed for service. Many drain lines had “settling pools” — basin-like areas in which the water would slow down enough to deposit some of the sediment it carried. In a rudimentary form of sewage treatment, the pools would be emptied out and the deposited sediment probably used for fertilizer.
In the upper town was the Great Bath, a forty-foot-long, eight-foot-deep sunken pool in the middle of a plaza that archaeologists have called humankind’s first artificial swimming pool. In the lower town, almost every house had a similar, smaller replica — a square, shallow basin, perhaps three feet on a side, against an outside wall. The basin sloped toward a floor-level outlet in the wall that drained into an outside “catchment vessel,” a kind of ceramic tub, which in turn led to a public drain (or, in some cases, could be dumped into one). By the bathing area was a toilet — a seat with a hole — that also deposited into the catchment vessel. Partly because linguists have not yet deciphered the Indus Valley script, details of daily existence in Mohenjo-Daro remain unknown. But bathing in clean water was clearly a focus of the city’s social life.
The reason to describe this long-ago city in such detail is that the technology deployed in the Indus Valley would not be surpassed, or even much changed, until just a few centuries ago. Imperial Rome, at its height likely the world’s biggest, most sophisticated city, had a water system that would have been familiar to people from Mohenjo-Daro, more than two thousand years before. Like its predecessors, Rome took advantage of gravity to make water flow from springs and rivers in the high hills outside the city into public facilities on the streets below. Perhaps the biggest difference was that the water from the hills came into the city on a series of aqueducts — bridge-like constructions that channeled water across valleys.
Rome, like Mohenjo-Daro, had a web of sewers that channeled away stormwater and wastewater. In Rome, that effluent flowed into a giant pipe called the Cloaca Maxima, which conducted the water into the Tiber River. Traveling downriver, the solid particles in the waste would drop to the riverbed; whatever remained would be diluted by flowing into the sea. The Roman model was replicated around the world for centuries. Louis XIV’s Paris dumped its waste into the Seine River; James Madison’s Washington, D.C., into the Potomac; Queen Victoria’s London into the Thames.
Despite having been employed for thousands of years, this method had an obvious drawback: it polluted the river, creating a terrible stench and making people sick downstream. Actually trying to clean up sewage, as opposed to sluicing it elsewhere, was rarely considered. Sometimes governments used wastewater for irrigation, a practice that, again, goes at least as far back as Mohenjo-Daro. In East Asia, excrement-filled water was often dispatched to “sewage farms,” which used the water as fertilizer. In 1531 the first European sewage farm opened in Bolesławiec, in what is now western Poland. The idea was slow to spread; France and Germany did not begin operating them until the nineteenth century.
The Industrial Revolution led to a dramatic increase in water use in urban factories. The resulting waste led to an equally dramatic decrease in water quality that fostered disease, especially cholera. Cholera is caused by drinking water contaminated with the bacterium Vibrio cholerae; sufferers have diarrhea so violent that it can kill them within hours if untreated. London, capital of what was then the world’s biggest, richest, most technologically advanced empire, experienced cholera epidemics in 1832–33, 1848–49, and 1853–54. Each time, thousands died.
During the 1854 epidemic a physician named John Snow traced the outbreak to a single contaminated city well. Politicians thundered against filth and disease but did next to nothing. They didn’t even keep the well closed. Four years later, hot weather reduced the flow of the Thames, which caused raw sewage and industrial waste to pile up on the banks. So overwhelming was the Great Stink of 1858 that Parliament was forced to act. Clamping scented handkerchiefs over their faces to stifle the smell, legislators finally voted to extend, enclose, and revamp the city sewer system.
Aiding London’s municipal engineers in the city’s belated upgrade was the first major innovation in water treatment for thousands of years: the pump. Although pumps are known from as far back as ancient Greece, they were not deployed on a large scale until about 1700, the beginning of the industrial era. Big pumps powered by coal-burning engines allowed London and many other cities to channel huge quantities of wastewater away from the city.
As a rule, pumping was deployed not to treat sewage but simply to flush it somewhere else. Cities piped the effluent into a river, lake, or shoreline further from the city — moving the problem, rather than solving it. But as urban populations grew, shunting away pollution became ever more difficult, both because the volume increased and because the land and waters around the city rose in value and their owners no longer wanted to accept it. The measures adopted by London after the Great Stink proved insufficient, as did other, similar measures elsewhere. Between 1898 and 1915, a British royal commission investigated the sewage problem. In a series of reports, it set the standards for most modern water systems.
One of its most historically significant recommendations was to separate storm water and sewage. Sewers have two main functions: carrying away storm water so neighborhoods don’t flood, and carrying away waste so they won’t be smelly and disease-ridden. Ancient and medieval sewer systems mixed both tasks, which meant that cities were covered in filth when heavy rains made sewers overflow into neighborhoods. Separating the two functions would not only keep the streets cleaner during storms but also reduce the burden on sewage-treatment systems.
Today, sewage treatment occurs in three steps, in an ascending ladder of squeamishness. The first, primary treatment, is an update to the old method of dumping effluent into rivers and lakes, except that it involves channeling diluted sewage into large tanks or basins. (Often it is passed through a screen along the way, which removes big, floating objects like sticks that might damage equipment.) Developed by several European sanitary engineers in the mid–nineteenth century, primary treatment is an advanced version of the settling pools in Mohenjo-Daro. As the water sits in the basin, the most disagreeable solids settle to the floor or float on the surface. Afterward, the muck is removed, usually by big paddles that sweep over the surface and floor of the tank, and then buried in landfills. In a few places, it is still spread on land and converted to fertilizer. Occasionally it is burned.
Secondary treatment, the next step, was invented by three researchers at the University of Manchester: Gilbert Fowler, Edward Ardern, and William Lockett. Now almost forgotten, the names of Fowler, Ardern, and Lockett should be emblazoned on city gates, for secondary treatment has made cities around the world into far more salubrious places. Nobel prizes have been awarded for advances far less consequential.
Primary treatment does not remove fine sediments — the water is often still vile. In a set of experiments in 1913, Fowler, Ardern, and Lockett added bacteria-rich sludge to the water from primary treatment and aerated it in much the same way that aquarium owners aerate their fish water with a bubbler. Aeration creates high oxygen levels in the water that encourage the bacteria to consume the remaining organic matter. After eating their fill, the researchers discovered, the bacteria sink to the bottom, where they can be scraped away for reuse. The recycling process is called, unromantically, “activated sludge.”
The water produced from secondary treatment looks and smells clean but still may not be potable, because neither primary nor secondary treatment eliminates all noxious chemicals and microorganisms. In a final step, tertiary treatment, the water is filtered again, for example by passing it through big towers full of sand. Then, depending on the facility, a variety of techniques are deployed to make the water potable. These include sprinkling chemicals in the water to remove nitrogen and phosphorus, adding chlorine or beaming ultraviolet radiation to kill remaining microorganisms, or forcing the water through a super-fine membrane that allows water molecules to pass through but not dissolved contaminants. All of these are costly, which is why governments typically have resisted them until forced to adopt them by public pressure.
These systems clean up water that people have used. Analogous systems are required to make water from wells, rivers, lakes, and so on potable. Different systems are used for different water sources in different places, but typically the incoming water must be filtered, clarified, and disinfected. And these steps, too, are costly, and have their own history of governmental foot-dragging.
Journalists have an expression: MEGO, meaning My Eyes Glaze Over. It stands for worthy and important subjects that people regard as too dull to think about. Water supply seems to be the essence of MEGO. Fixing urban networks is so expensive, time-consuming, and invisible to the public that governments historically have been unwilling to pay attention unless forced by disaster. Sometimes they have tried to hand the problem to private industry, but water is so obviously a public concern that in many cases the citizenry has resisted. All too often, the result has been systems that stagger along at barely satisfactory levels.
Cairo, Buenos Aires, and San Antonio; Dhaka, Istanbul, and Port-au-Prince; Miami, Manila, Monrovia, Mumbai, and Mexico City — all have greatly expanded in recent decades, and all have failed to keep up with the demand for clean, plentiful water. The statistics are stark. At a global scale, 40 percent of waste water is dumped without being safely treated, and 24 percent without being treated at all, which leaves about 2 billion people using water that can be polluted by feces, chemicals, or other contaminants.
The United States is better off than many places, but it has its own problems. Big public programs in the 1960s and 1970s gave us water systems whose cleanliness and reliability would have seemed like miracles in Johnny Appleseed’s day. The system our forebears constructed is vast: approximately 150,000 public drinking-water systems and more than 16,000 public waste-water treatment systems. These serve roughly 80 percent of the U.S. public. (The remainder have private wells and septic tanks, which are typically inspected by local governments when installed.)
But now these systems need to be rebuilt. Growing demand, increasingly severe droughts, and, above all, aging infrastructure are testing their limits. Almost half a million miles of pipe in North America is nearing the end of its useful life and will need to be replaced soon. Equally in need of upgrades are the thousands of treatment plants built in the 1970s. The U.S. Environmental Protection Agency estimates that maintaining the nation’s drinking water and waste water infrastructures will cost at least $1.2 trillion over the next twenty years. Water experts have been warning about these looming problems for decades. But nothing like the required sums has been committed. History suggests that the systems will not be maintained until there are several disasters. But the disasters could be avoided if voters understood the importance of their water supply, and made clean water a priority.
