Cities have always had to deal with an intriguing problem, procuring adequate drinking water — and carrying off, or diluting, wastes. The simplest approach — dumping wastes in the nearest watercourse and drinking from it too — worked only where people were few and water plentiful.
A history of sophistication
More complex approaches emerged, aiming to segregate drinking water from waste water, even early in human history. After all, for urban dwellers, failure in these efforts meant disease and early death. Toward the end of the 19th century, new insights into the transmission patterns of cholera (in the 1850s) and typhoid (in the 1880s) concentrated attention on urban water quality.
|Back in Roman and Byzantine times, engineers erected dams and aqueducts and dug giant cisterns to address the problem.|
The stories of Istanbul, an old city with scant fresh water, and of Chicago, a new city with plenty, provide a great illustratration of the issues and strategies in urban water supply and urban sewage management.
Istanbul (once Constantinople and before that Byzantium) has a long history of sophisticated waterworks. Its location, while strategic and spectacular, provided it with very limited fresh water, in the form of a stream that flows into the Golden Horn, Istanbul's historic harbor. The city's population easily polluted this water supply to the point where it was dangerous to drink.
Shortages of clean water constrained the city's growth. Engineers in Roman and Byzantine times erected dams and aqueducts and dug giant cisterns to address the problem. When the Ottoman Turks captured the city in 1453 and made it their capital, they built still more aqueducts, most of them during a great 16th-century expansion of Istanbul.
Sinan, perhaps the greatest architect of his day, designed much of Istanbul's water system. With this infrastructure, Istanbul collected water from distances of 20 to 30 kilometers away, allowing it to become one of the world's largest cities by 1600. Its far greater growth in the 20th century required much more water.
Emerging from the ashes
|Between 1885 and 1886 alone, 90,000 people around Chicago (including 12% of the city's population) died of waterborne diseases.|
Consequently, while some of the Ottoman systems remained in use, Turkey — which emerged from the ashes of the Ottoman Empire in 1923 — built several new dams and pipes. They extended the aquatic reach of Istanbul to more than 120 kilometers.
The new republic moved the capital to Ankara in the 1920s, which slowed the growth of Istanbul. But by the 1950s, rapid population growth throughout Turkey and rural exodus swelled the population's size by 10% per year.
Most of the new arrivals built their own housing on the edges of the city, and lived without piped water or sewage. These settlements sprawled in every direction in the 1960s and 1970s, and eventually their residents acquired enough political weight to extract favors from the government, such as connection to the city water and sewage systems.
After 1980, Istanbul (with a population nearing 10 million people) drew heavily on water from the Asian side of the Bosporus, carried beneath The Straits by pipe. Even this proved insufficient in the 1990s, when summertime often required strenuous water conservation.
Problem of supply
As in many cities around the world, water supply continued to vex authorities responsible for accommodating urban growth — and ordinary people who had to make do with less.
|After 1900, when Chicago no longer emptied its waste into its water supply, the New York Times offered as a headline: "Water in Chicago River Now Resembles Liquid."|
In contrast to Istanbul, Chicago is a young city on one of the largest lakes in the world. But it too developed water problems with its rapid growth in the 19th century. Its population used the lakefront and the Chicago River (which flowed into Lake Michigan) to dump its wastes, contaminating the water supply.
Outstripping the pipes
What 30,000 Chicagoans dumped into the river and lake in 1848 caused only modest problems. But when the city's population boomed after the Civil War, old arrangements had to change. City authorities built longer and longer pipes out into the lake to try to draw water unsullied by the city. But Chicago's rapid growth continually outstripped the pipes' reach.
Until 1900, Chicago — to its detriment — had a well-deserved reputation for typhoid. Between 1885 and 1886 alone, 90,000 people around Chicago (roughly 12% of the city's population) died of waterborne diseases.
Sickness from sewage
Typhoid sickened about 20,000 Chicagoans a year from 1891 to 1895. These epidemics provoked America's largest engineering project before the Panama Canal: the Chicago Metropolitan Sanitation District. It reversed the flow of the Chicago and Calumet Rivers, so that by 1900 they no longer emptied into Chicago's drinking water supply. Instead, they flowed toward the Illinois River — and down to the Mississippi.
Thus, the sewage of Chicago, including biological waste from the world's greatest stockyards, no longer menaced Chicagoans, but drifted away to Joliet, St. Louis and New Orleans. Typhoid and other waterborne epidemics became only memories. The New York Times offered as headline news: "Water in Chicago River Now Resembles Liquid."