The Source

by Martin Doyle

  Laborers raising Briggs House, a Chicago hotel, in 1857.

  Chicago’s topographic predicament is a lesson in the influence that sewage has over cities: buildings and streets can be corrected and adjusted; power lines or phone lines can be sagged and drooped and meandered about sprawling suburbs. But a pipe carrying sewage is an uncompromising necessity with particular topographic demands. By adjusting the topography, Chesbrough had managed to dry out the city. But in doing so, he exacerbated another problem. All of the sewage from the city and its factories was now carried that much more efficiently into the Chicago River and on to Lake Michigan, the city’s source of drinking water.

  Most early American cities sat on a major river or an estuary. Residents drew their drinking water from upstream and dumped wastewater downstream. A city on a lake presented a novel problem, for the source of water also had to be its toilet. This issue was something that Chesbrough, among many others, had long been wary of—and for good reason. In 1851 Chicago had lost 5 percent of its residents during a cholera outbreak, which was the impetus for hiring Chesbrough. But the contamination problem remained, even after the new sewer system was completed: in 1885, when over five inches of rain fell in 24 hours, rapidly flushing the city’s waste into the lake, the resulting outbreak of waterborne diseases killed an estimated 12 percent of Chicago’s population. Other cities had long since constrained waterborne disease; the highest typhoid rate between 1860 and 1900 was 4.7 per 10,000 inhabitants in a single year in New York, 6.4 in Philadelphia, and 8.6 in Boston. In Chicago, the rate exceeded 10 per 10,000 residents in eight different years over that period. Quite simply, Chicago’s water and waste disposal systems made it a dangerous place to live. The solution that had once been financially unthinkable began to seem unavoidable.13

  In the summer, rivers are slippery. Fly-fishermen often use felt-soled boots with their waders to help them stay upright and somewhat graceful as they scramble over riverbeds covered with “schmutz.” The schmutz—a slimy, filmy substance that builds up on the rocks and gravel of streams and rivers—is critically important to the ecology of rivers. Most scientists don’t call it schmutz, preferring instead the technical terms biofilm, periphyton, or even, drawing on the German roots of river science, aufwuchs (“overgrowth”). Regardless of what it’s called, schmutz is a gumbo of bacteria, algae, and viruses as well as bits of dead plants. These organisms, the things they eat, and the things they excrete make up an ecosystem within an ecosystem, the study of which is now known as microbial ecology. This micro-ecosystem—or microbial community—also exists in the moving water of the river. A tiny fragment of a dead leaf, or even a particle of sediment, quickly acquires a community of bacteria determined to squeeze every last bit of food from its surface as it is whisked downstream. Most of the ecological work that takes place in fresh water is done by bacteria, and as long as there is oxygen in the water, bacteria will be there to consume organic pollution—including human waste.

  The existence of this micro-ecosystem means that rivers, streams, and creeks are not sterile pipes that convey whatever is delivered to them to its destination in exactly the same form. Rather, anything put into a river is processed by the microbial ecosystem that lives in that river. Rivers are self-purifying. At least, that’s what William Sedgwick claimed.

  If Chesbrough, with his expertise in hydraulics and conveying water, represented the epitome of the mid-nineteenth-century water engineer, then Sedgwick was the consummate twentieth-century water engineer. Sedgwick spent the bulk of his career on the banks of the Merrimack River, which in the late nineteenth century was one of America’s most developed—and consequently most polluted—rivers. It flowed through the mills and mill towns of the New England textile empire. All the waste and sewage generated by that textile empire was funneled into Lawrence, Massachusetts, whose geographic curse was being the most downstream town on the Merrimack.

  At the turn of the twentieth century, a small research station was established in Lawrence right along the Merrimack River to study public health, especially the link between water and microbes. This water research station was run jointly by Harvard and MIT and was the precursor to what eventually became Harvard’s School of Public Health. As its director, Sedgwick became the patriarch of modern water engineering.

  Sedgwick initially pursued medicine at Yale; but after a few years, he shifted his focus toward the infant field of microbiology and finished his PhD, rather than an MD, at Johns Hopkins. Sedgwick was part of the bacteriological revolution of the late nineteenth century, an era that witnessed enormous breakthroughs as the links were finally made between contaminated water and disease. Before the work of these scientists, many diseases were attributed to miasma theory, the idea that putrefying wastes emitted pollutants into the air. Thus, foul smells were indicators of potential contamination. Disease outbreaks in cities were blamed on air rather than water, a partial reason for the focus on open boulevards and urban parks in early twentieth-century city planning. However, in the early 1890s a group of scientists and engineers led by Sedgwick scientifically confirmed the relationship between sewage-contaminated waters and typhoid fever, the great scourge of cities.

  From his perch at the water experiment station in Massachusetts, Sedgwick became the sage of water, promoting its link to public health and the need for civil engineers to think as much about microbiology as about drainage. He also advocated for the treatment of water to avoid disease. Fortunately, in addition to identifying the impact of polluted rivers on public health, researchers of this time provided the means to clean river water: filtration and chlorination. With these methods, any city had invaluable tools to radically improve its public health by treating contaminated incoming water to remove the disease-causing microbes.

  In addition to the direct treatment of water, Sedgwick also advanced the idea that running water was “self-purifying,” or, as captured by a group of scientists: “Any stream will, if given time enough, that is to say, length enough, practically purify itself after receiving a given amount of sewage.” Indeed, prominent texts of the time on water engineering, along with the leading research journals, began linking the natural processes of streams and rivers with water purification. Rivers were praised for their ability, with time and space, to take care of public health problems as well: “A few years ago it was stoutly denied that rivers had the power of purifying themselves. Then we knew practically nothing of nature’s method. Now, that this has been so far revealed to us, it is declared with equal force that not only are effete matters rendered innocuous, but even disease-producing microbes are themselves voraciously devoured by others of like kind, and the formerly much-dreaded bacteria are—and properly so—considered amongst the best friends of man.”14

  Once Sedgwick and the growing water science and engineering community had shown that the combination of river self-purification and contemporary water filtration and chlorination was effective in removing disease-causing bacteria, they had established the justification to continue polluting rivers without restraint. As they argued, pollution of rivers would eventually be self-purified, and so society should harness the natural services provided by running water. Moreover, cities could always—and should always—treat the water they took in and distributed. As a result of these attitudes based on new scientific and technological discoveries, the most prominent water engineers of the era were justifying the practice of cities dumping their waste directly into streams and rivers untreated—as long as water was treated when used for supply, as quickly became the standard by necessity.

  Sedgwick’s philosophy of relying on river self-purification and water supply treatment was gospel to engineers but anathema to physicians. The use of self-purification to justify pollution marked a deep ideological divide between those like Sedgwick—who would become known as sanitarians or sanitary engineers and, eventually, environmental engineers—and those who had to deal with the consequences of sewage: the physicians and public health officials. The debate wa
s not over what caused the diseases, but rather over how much financial cost cities should be expected to bear for water treatment.

  Waste treatment before disposal would impose considerable costs on an upstream city to the benefit of a downstream city; and at the time few, if any, regulations required such treatment, let alone funding available to subsidize it. Moreover, because most cities had combined storm sewers with sanitary sewers in the model of Chesbrough’s water carriage system, the volume of wastewater that would need to be treated was enormous—well beyond what could be handled by even the most aggressive of existing sewage treatment works. The presumption was that all cities would treat water at their point of use. If cities also treated their sanitary sewage before dumping it into rivers, then rivers and streams would be relatively unpolluted and cheaper to treat when used as source water. If instead cities were responsible for treating their water only at the point of use, then rivers would be much more widely and severely contaminated, and each water supplier would bear heavier costs to improve the quality sufficiently for safe use. One path led to some preservation of water quality in streams and rivers; the other led to vast pollution as every city primarily took care of itself.

  Physicians have always been highly regarded in society, and municipal boards of public health had almost uniformly placed the task of water quality regulation under physicians. Yet, at the turn of the twentieth century, engineers were gaining a level of respect that challenged even that of physicians. In contrast to physicians, whose work in this era tended to be patient by patient, engineers in the early twentieth century were building the modern wonders of the world: monumental dams, sprawling road networks, complex bridges, and towering skyscrapers. Through their vast improvements to infrastructure systems, engineers were transforming society in grand leaps.

  Sanitary engineers sought to do for sewage what their counterparts were doing with dams and bridges. These new engineers were biologists and hydrologists by training but planners and builders by practice. They were well versed not just in cholera and typhoid but also in landscapes, pipes, streets, and, crucially, budgets. As sewers and water supply systems became the skeleton and sinews of the modern urban landscape, engineers took on the expansive task of urban planning and, eventually, the role of city managers. They leveraged this role to establish their view of rivers as grand sewers of convenience for society. The argument proved compelling to other city officials, just as Chesbrough’s appreciation for fiscal constraints had engendered enormous trust in his unusual plans to raze and then raise Chicago. As planners and city managers, engineers were involved in the fiscal realities and responsibilities of urban planning.15

  Based on their role of solving both technical and fiscal problems for city governments, sanitary engineers argued that cities were responsible only for treating incoming water to provide clean water for their residents; they were not responsible for treating the sewage. Earlier engineering decisions set in motion by Chesbrough to combine storm and sanitary sewers now made sewage treatment all but impossible economically due to the sheer volume of water needing to be treated. The engineering community stubbornly took the line that it was not only preferable, but—as expressed in an editorial in the Engineering Record in 1903—“more equitable” for cities to be responsible only for water treatment at the intake and that they be allowed to discharge sewage into a stream untreated.

  Their mixed mandate for public health and fiscal health shielded engineers from having to protect or be concerned with the need for sewage treatment before its disposal in streams and rivers. In a particularly rosy self-evaluation, a 1912 editorial in Engineering News boasted that the sanitary engineer was “a true and the greatest of conservationists, zealous to safeguard health and prolong life, but sparing no pain to see that each dollar is spent to the best advantage.” Engineers used their awareness of fiscal constraints as a trump card to place their insight above that of idealistic physicians; they argued that it was engineers who had the unique and superior conception of the relative needs and values of municipalities, and they lumped together the entire medical community as “sentimentalists.” In the end, the engineers won the battle, if not the war: in the first decade of the twentieth century, almost 90 percent of total collected wastewater ran into streams and lakes as raw, untreated sewage.16

  All these aspects of that time—Chicago’s flat topography, the science of self-cleansing rivers, and the acceptance of cities dumping pollution untreated into rivers—combined to bring about Chicago’s second great topographic twist. While cities on a river could simply take water from upstream, treat it, and dump the waste downstream, Chicago was using Lake Michigan as both its faucet and its toilet. The only potential long-term solutions were to treat water as it became increasingly foul or continue to move Chicago’s water intake farther out into the lake, beyond the reach of the polluting river. The city certainly attempted the latter plan: in addition to following Chesbrough’s drainage and sewer plan, it also followed his instructions to build a new water intake two miles farther out into the lake, outside what was thought to be the reach of contamination. From this extensive distance, water was piped into the city through a series of over 240 miles of water pipes laid throughout the city. But even then, the problem remained that Chicago was producing enormous amounts of waste: by 1860 its population exceeded 100,000 people, and its stockyards were slaughtering almost two thousand head of cattle, sheep, and hogs daily. The wastes of this meat-packing empire flowed inevitably to the river, which became the city’s festering open bowel. Or, as described in 1880, the South Branch of the Chicago River was “in an abominable condition of filth beyond the power of the pen to describe.”17

  Large rainstorms could flush out the river more fully into the lake, potentially reaching the water supply intakes. And so, the city decided to use its geography to separate the pollution from its water supply. The city would adopt what had seemed only three decades earlier to be an impossible plan; it would make the Chicago River flow backward.

  Reversing the flow of the Chicago River was possible only because of the region’s once problematic flatness. In fact, in its initial recommendation to investigate the river reversal, a commission noted that it was “practicable to restore the ancient outlet of the Great Lakes by opening a channel across the Chicago Divide, thereby creating a waterway to the Gulf of Mexico.” The plan was simply to restore the ancient flow path. The eventual result was a 28-mile-long channel that served as both a sanitation drain for the city and an expanded navigation channel. The new channel, known as the Chicago Sanitary and Ship Canal, ran parallel to the older Illinois and Michigan steamboat canal. It was massive in comparison to the old one and substantially deeper, allowing passage of much larger boats than the previous canal could have accommodated. More to the point, the same qualities that enhanced navigation were also designed to pull water from Lake Michigan, so that Lake Michigan was no longer the outlet for the Chicago River but rather the headwater. The Cal-Sag Channel to the south similarly flipped the flow of the Calumet River away from the lake and joined the main canal flowing away from Chicago.18

  The Chicago River, before and after it was reversed to drain into the Mississippi River.

  By pulling a continual flow of water in from the lake, the backward-flowing Chicago River allowed the fetid water to drain out and used the relatively clean water that remained to flush the pollution from tributaries, which it had now also diverted away from the lake. The engineers’ critical concern was ensuring that the volume of water drawn from the lake would always be high enough to force the river backward—even during rain events. The initially designed and implemented flow that passed through the main channel was 10,000 cubic feet per second (cfs), just a bit less than the flow of the Colorado River as it passes through the Grand Canyon. The reversal worked exactly as planned for Chicago, but not for the downstream cities toward which its pollution was now careening: the switch drove the former Chicago River waters out of their normal watershed region i
nto the Des Plaines River, which connected to the Illinois and Mississippi Rivers. As the historian Louis Cain describes the resulting revised geography, “Chicago was using the Great Lakes drainage area for its water supply, and the Mississippi River drainage area for its sewage disposal.”19

  This hydrologic coup d’état was politically possible because of the convoluted protocol for pollution treatment being championed by engineers. Sedgwick’s vision of self-purification was crucial in determining how the newly downstream communities responded to the shift, now that all of Chicago’s wastes were being swept through central Illinois and eventually on to St. Louis. Towns along the Illinois River, like Joliet and Peoria, were glad for the additional water to keep the river navigable during dry periods and for the subsequent increase in river traffic. But St. Louis, the other primary city of the Midwest, was less cheerful because the increased flow corresponded to what St. Louis thought was going to be dramatically increased pollution. Yet the river was in fact able to process the wastes along its course. Due to the length of the river flow and the constant oxygenation of the water, the microbial community could process the vast wastes in the river before it even reached Peoria, Illinois, much less St. Louis, Missouri.

  In summarizing a vast array of studies on the subject, a series of academic scientists concluded: “It is evident that the Illinois River is capable of purifying itself to a very marked degree. The organic evidences of the Chicago sewage, as well as that introduced between Chicago and Peoria, have disappeared at Peoria, and we find the Illinois River at this point in as good a condition as the tributary streams.”20 Essentially, Chicago’s adoption of Sedgwick’s ideas about the self-purifying capabilities of rivers enabled the city to take the drastic step of reversing the river, and the same belief among the downstream communities made them willing, for a time, to accept it.