Drinking Water

by James Salzman

  THE BURIED PIPES THAT CHANNEL WATER TO OUR FAUCETS AND carry wastes from our drains form the skeleton of our distribution system. Out of sight, our water and sewage pipes never inspire a second’s thought until they fail. This willful ignorance creates a real problem, however, because our nation’s water infrastructure has become increasingly enfeebled.

  While a rough measure, every two minutes a major water line bursts in the United States. It may be in Topeka, Kansas, or Tucumcari, New Mexico. In our nation’s capital, Washington, D.C., the rate is about one pipe break a day. When I lived there, I was shocked to come home one day and see a geyser bubbling in the middle of the road in front of my house. The massive pressure from a burst line had forced water from five feet underground up to the surface, casting aside large slabs of asphalt.

  The cause in all these cases is the same: inadequate investment in our pipes and treatment plants. Some of our water and sewer lines date from the Civil War. Many more were built in the 1900s. The massive pipes described in Chapter 2 that supply New York City are leaking thirty-six million gallons per day. Engineers fear that their structural integrity has become so compromised that draining the pipes for repair might cause them to buckle and collapse under the weight of the soil on top. Residents in some areas of Washington, D.C., cannot drink from their taps because of lead in their water, released from the lead soldering used to join the household pipes decades ago. On average, Philadelphia has to deal with more than two breaks in water and sewer lines every day.

  Despite the obvious importance, gaining funding to rebuild our water and sewer lines has proven elusive. In recent memory, when hundreds of billions of dollars of TARP money was being disbursed by Congress for “shovel-ready” projects, only $2 billion was dedicated to water projects. People point to the Clean Water Act’s tough regulations as the explanation for why our nation’s water quality has improved in recent decades. These regulations have been significant, but equally if not more important were the billions of dollars provided to states and municipalities for the construction and enhancement of water treatment and sewage plants.

  Perhaps the failure to invest in our water infrastructure should not be surprising. These arteries and veins of our water system are invisible, buried beneath roads, fields, and buildings. The only time we think about them is when they no longer work. And the sums required to remedy the decades of underfunding are massive. The EPA estimates we need $335 billion simply to maintain our drinking water systems. New York alone claims to need $36 billion to maintain its wastewater systems. To be sure, these are large sums, but compared to what? How much would it cost were our water distribution and treatment systems to fail? It is no exaggeration to say that we are playing on borrowed time as our aging water infrastructure continues to give way.

  SO HOW ARE WE DOING? FOR THE PAST CENTURY, THE UNITED STATES has paid increasing attention to eliminating the scourge of waterborne contaminants, and the results have been impressive. Most people can drink their tap water, confident in its safety. Most, but not all. Estimates vary, but the New York Times reports that roughly nineteen million Americans become sick each year from waterborne parasites, viruses, and bacteria. A study by UNESCO found that E. coli and other waterborne pathogens result in about nine hundred deaths of Americans every year. Not all of this is the result of tap water, but safe water is by no means guaranteed, even today.

  The single greatest outbreak of waterborne illness in U.S. history occurred just two decades ago, in 1993, when the city of Milwaukee was terrorized by a tiny parasite in the drinking water, Cryptosporidium parvum. For two weeks, the city’s Howard Avenue treatment plant provided contaminated water to people’s faucets. The plant’s intake was located at a site in Lake Michigan that directly received the discharge of the Milwaukee River, making the plant’s intake susceptible to a recent fecal contamination. More than 400,000 people, roughly one-quarter of the city’s population, became ill with stomach cramps, diarrhea, and fever. Those with weak immune systems were most at risk, and sixty-nine people died.

  The problem here was not failure to regulate. Cryptosporidium is a well-known microbe. Rather, this was a simple case of human error—with tragic results. Just as in ancient Rome and Victorian London, safe drinking water cannot be guaranteed without proper source identification, protection, treatment, and distribution. Breakdowns in any of these areas can lead to disaster, and the sheer scale of modern-day water consumption virtually ensures that some contaminants will eventually make it through. Looking back through history, however, we can take heart that even though the dangers remain very real, we’ve come a long, long way toward controlling the risks. Of course, it is one thing to combat disease-causing microbes, which generally present obvious symptoms and can be diagnosed quickly. But what if the problem is harder to detect and takes much longer to show its harm?

  HOW DID VENICE GET ITS DRINKING WATER?

  Venice is one of the great marvels of the modern world and a most unlikely place. In the 13th and 14th centuries, Venice reigned as the wealthiest city in Europe and arguably in the world. Its fleets dominated trade in the Mediterranean region. Yet it was entirely artificial. Originally a series of settlements on 117 small islands lying across a shallow lagoon, the city we know came into being through ingeniously reclaimed land. Over centuries, thousands of wooden piles were driven into the thick sand and mud until resting on the harder layers of clay below. These provided solid foundations for the sea walls and infill creating the larger islands we admire today, stunningly interlocked by canals and footbridges. Its admirers call Venice “La Serenissima”—The Most Serene.

  In terms of drinking water, Venice more resembles a ship than a city, for there are no ready sources of surface water or groundwater. An early observer wrote, “Venice is in the water and has no water.” How did one of the most populous cities in the West provide water to its citizens? It looked to the sky.

  Rainwater falling from roofs and streets flowed into town squares (campi), where it was directed into specially designed cisterns. The cisterns were built by digging a ten foot pit beneath the campi, its sides lined with impermeable clay. A hollow cylindrical shaft would be built in the center of the pit, rising to street level and formed by special curved bricks known as pozzali. The rest of the hole would then be filled with sand and the pit covered over with stones. Someone strolling along the campi would notice a well-head in the center (capping the cylindrical shaft below) and, at each corner, perforated stone slabs through which water could flow into the pit below. Over time, the pit would become saturated with rainwater, purified as it passed through the sand. The water would make its way through the bricks forming the cylindrical shaft and into the well, but the larger sand particles would be filtered out. From the wellhead, water was free for the taking from the shaft below. Centuries before science knew the first thing about microbes, Venice likely provided the cleanest urban drinking water in the world.

  A cross-section of the well shaft and sand drainage in a Venetian square

  This system served well until the 16th centurye. Venice had stopped reclaiming land so the increasingly dense population needed somewhere to live, making open space scarce. This posed a real problem because the system of cisterns beneath the campi required large amounts of unbuilt urban areas to collect rainwater. The Venetians adopted an ingenious new strategy. Campi were lost to new construction, but dwellings were now required to build a cistern within their foundations. Rainwater falling on the roof was collected by gutters into clay pipes built into the walls that led directly down to the cistern below the basement. By the middle of the 19th century, there were over 6,000 of these “inside cisterns.”

  Venice is a city of visual delights, from the sleek black gondolas and graceful bridges to the ornate churches and balconies astride the canal waters. Yet perhaps the most marvelous accomplishment of all, the source of clean water during La Serenissima’s years of power, lies unseen beneath the plazas and tourists’ steps.

  4


  Death in Small Doses

  ARSENIC HAS LONG BEEN THE MURDERER’S POISON OF CHOICE. Clear when dissolved, odorless, tasteless, it is almost too easy to slip some of the deadly white powder into an unsuspecting person’s food or drink. In cases of quick poisoning, the victim feels cold, clammy, and dizzy with painful stomach cramps. Death follows shortly after. Arsenic’s effectiveness and ease in dispatching people was the driver behind the classic play and movie Arsenic and Old Lace, where two well-meaning though misguided women eased the passage to the hereafter for lonely widowers enjoying their cookies and poisoned elderberry wine. The most famous historic case of arsenic poisoning may have involved Napoleon, who died on the distant island of St. Helena after his grand attempts of conquering Europe had failed. While the diagnosis at the time of the emperor’s death was stomach cancer, modern analysis of his hair suggests arsenic poisoning.

  Arsenic is not only lethal when delivered intentionally, however. The compound also occurs naturally in the common mineral arsenopyrite. When these rocks erode, arsenic is released into the soil and groundwater. Even the most reckless person knows that drinking arsenic is a bad idea. Yet, just a decade ago, controversies over how much arsenic people should drink in their water led to public furors in both the world’s wealthiest and poorest countries, with very different results.

  One of the most densely populated and impoverished countries in the world, Bangladesh sits in the delta of the Ganges and Brahmaputra rivers. Access to freshwater is not a problem—quite the contrary, as the country often suffers from seasonal flooding. Unfortunately, these rivers are heavily polluted as they move downstream and are thus unfit for drinking. Traditionally, Bangladeshis have relied on surface waters from ponds and shallow wells for their domestic water use. Pollution from inadequate (often nonexistent) sewage systems, however, has made high death rates from cholera and diarrhea commonplace, particularly among the young. Seeking to remedy this public health problem, the World Bank and the United Nations Children’s Fund (UNICEF) agreed to fund a nationwide program. The ambitious goal was to shift domestic sources from surface water to the country’s plentiful groundwater. Groundwater is generally safer than surface sources such as lakes or rivers because the soil filters bacteria and pollution as water percolates down into the aquifer. Literally millions of tubewells—shallow pipes operated by steel hand pumps—were eventually sunk throughout the countryside.

  On the surface, this seemed a poster child for what development aid should be all about, providing simple, inexpensive, and effective technology to overcome a terrible public health challenge. Victory was quickly and confidently declared. As researchers later described:

  A tubewell became a prized possession: it lessened the burden on women, who no longer had to trek long distances with their pots and pails; it reduced the dependence on better-off neighbors; and most important, it provided pathogen-free water to drink. By the early 1990s ninety-five percent of Bangladesh’s population had access to “safe” water, virtually all of it through the country’s more than 10 million tubewells—a rare success story in the otherwise impoverished nation.

  While the aid groups were congratulating themselves, however, tests of the groundwater revealed a tragedy unfolding. Many of the plentiful freshwater aquifers were located in soils containing arsenic. It had not occurred to any of the engineers to test for naturally occurring arsenic when the wells had been drilled, but it was surely there. Laid down in geologic strata over millions of years, the undetected arsenic had dissolved into the groundwater and was now being pumped up for drinking and domestic use.

  The largest public drinking water initiative in the history of Bangladesh had monstrously transformed into the worst case of mass poisoning in the world. Wells in fifty-nine of sixty-four of the country’s regions exceed the World Health Organization’s guidelines for arsenic in drinking water, and roughly 10 percent of the wells contain more than six times that amount. No one knows just how many people are at risk of arsenic poisoning, but the estimate in 2010 was well over seventy million.

  Acute arsenic poisoning can kill within a few hours. Much more common, however, and unlike most waterborne diseases, chronic arsenic poisoning can remain in hiding for up to ten years before revealing itself. The initial symptoms include black spots on the upper body, bronchitis, and loss of sensation. In serious cases, this gives way to swollen legs, cracking palms and soles, and renal malfunction. If the victim survives the likely threats of gangrene and kidney failure, cancer follows. A number of field projects tested wells, painting those with high arsenic levels red and those with low levels green, and this has had some effect. But most wells remain untested, and many people continue to draw their water from red wells.

  While Bangladesh and the international development community struggled to respond to their self-inflicted epidemic, halfway across the world, in the world’s wealthiest country, concerns over arsenic in drinking water were front page news, as well.

  The United States has had an arsenic standard of fifty parts per billion since 1942. Over the past few decades, however, studies in Argentina, Taiwan, and Chile have suggested harmful effects from drinking water with much lower arsenic concentrations. The Environmental Protection Agency and National Research Council started examining the issue and modeling the likely impacts from drinking water with concentrations below 50 parts per billion.

  In 2000, shortly before President Clinton left office, his administration proposed a new regulation lowering the legal limit to five parts per billion, comparable to one drop of arsenic in fifty drums of water. Faced with strong complaints by both water system managers and industry over the high costs of compliance and weak scientific case for a five-parts-per-billion standard, the administration doubled the limit to ten parts per billion, the same as that recommended by the World Health Organization. While the new standard would apply to all 54,000 of the country’s community water systems, it was estimated that only a small number of water sources, mostly in the West, would be affected. Specifically, regulators estimated that about 5 percent of the systems would need to take action, affecting the water for roughly eleven million people, plus an additional two million people not on community water systems. The rule was scheduled to go into effect in March 2001, two months after George W. Bush took his oath of office.

  One of the very first acts of the new Bush administration’s EPA, however, was to suspend implementation of the new arsenic drinking water regulations pending further study. The public response was loud and powerful, creating one of the administration’s very first controversies. Even the staunchly conservative Wall Street Journal thundered, “You may have voted for him, but you didn’t vote for this in your water.” Representative David Bonior was even more caustic. “If there is one thing we all seem to agree on it is that we do not want arsenic in our drinking water. It is an extremely potent human carcinogen.” Stating the obvious, he continued, “It is this simple: arsenic is a killer.”

  So why did the Bush administration take such a seemingly foolish action? The policy choice was whether to keep the current standard of fifty parts per billion or tighten it to ten parts per billion. It was well understood that the standard would impose significant costs, particularly on small communities. The question was whether it was worth the cost. One might assume it clearly was worth it, given the dangers from arsenic. No one wants to drink poison, even in small amounts, when they turn on their tap.

  Is arsenic in the water safe to drink at any level? Perhaps surprisingly, neither Americans nor Bangladeshis have been able to answer that question, but for very different reasons. For the Bangladeshis, the more relevant question is which water source is less unsafe to drink? As one researcher described, “It took about twenty years to move everyone from surface water to ground water and then in the 1990s we are suddenly telling people the groundwater can kill you.” While some have suggested that people be encouraged to go back to surface water, this poses real problems as well. After all, the harm from microbial disea
ses is why they switched to groundwater in the first place.

  In a recent study, 29 percent of the water users stopped taking their water from wells once they were told the water had high levels of arsenic. But that still leaves more than half of Bangladesh’s population exposed. As the researchers concluded, despite identifying many of the wells as either safe (green) or unsafe (red), “Even with complete identification of contaminated wells, rural households are left facing a dilemma: Use river or pond water and face waterborne disease, or use groundwater, if it is still within reach of hand pumps, and face slow poisoning from arsenic. Families without alternative sources of drinking water continue to use arsenic-contaminated tubewell water, and the response to poisoning has been slow and incomplete.” These same researchers found that where a green tubewell required a long walk, many families decided to rely on the nearby polluted water.

  In deciding which water is safer to drink, villagers are surely undertaking some sort of personal risk assessment. On the one side are the ease and modernity of using tubewell water, which they are now being told may be dangerous to drink. On the other is surface water, which they know can lead to cholera and diarrhea. Waterborne diseases in surface water strike quickly, making the connection between disease and water easy to draw. Arsenic is a slow killer, unseen until it strikes years later.

  This type of decision is known as a “risk-risk” choice. Each option comes with costs. As the saying goes, out of the frying pan and into the fire. Balancing the trade-offs in this risk-risk dilemma is complex, and most certainly not a purely technical question. Time spent going to a more distant green tubewell rather than a closer red tubewell can impose its own costs in lost time. And which water you drink can also be a status statement. As one field worker has described, “In conversations with villagers, we realized that although they want arsenic-free water, they do not want to feel that they are going back in time to methods they once discarded. Tubewells had fitted nicely with their forward-looking aspirations.”