TreeHugger often talks about the benefits of density, about the virtues of cities, about the lessons from Jane Jacobs. We also talk of the need for clean water and sanitation in so much of the world, how the death of millions of children is completely preventable. If one wants to understand how density became safe and how cities became answers instead of problems, there is no better place to start than Steven Johnson's The Ghost Map, "The story of London's most terrifying epidemic- and how it changed science, cities and the modern world".
In 1854 London, there was density without infrastructure; everything was recycled by" bone-pickers, rag-gatherers, pure-finders (dogpoop collectors who sold it to tanners) dredgermen, mud-larks, sewer-hunters, dustmen, night-soil men, bunters, toshers and shoremen, a hundred thousand strong. Recycling made the city work, because nobody had developed the networks of waste management and water supply needed to support such densities since Roman times. A few private water companies piped water from the Thames; otherwise one used the public pumps. Human waste was tossed into cesspools, rear yards, even basements, and the smell was awful. Prevailing wisdom said that disease was carried in the miasma, or in the air, and the more it smelled, the sicker one would get. Consequently the authorities started building sewer lines that carried water away from the cesspools and into the Thames, source of much of London's drinking water.
The lessons learned here resonate to this day. By 1868 London had a massive new sewer system and never suffered another death from cholera, which is now a scourge of the developing world. All of the squatter cities of Africa and South America are replicating the conditions of 1850 London, and two million children are dying each year.
Meanwhile, in the developed world, people are living in densities that let us live more efficiently, with better services and more vibrant cultures than anyone could imagine. We quote: "As environmental scholar Toby Hemenway says, "Virtually any service system- electricity, fuel, food- follows the same brutal mathematics of scale. A dispersed population requires more resources to serve it-and to connect it together- than a concentrated one" and as Jane Jacobs said, "Cities were once the most helpless and devastated victims of disease, but they became great disease conquerors."
Other reviewers consider Johnson's last chapter on the importance of dense cities to be a diversion, but it is critical to make the direct connection between what happened in 1854, with the subsquent massive state intervention to build a proper infrastructure of services to serve London, and with what is happening today both where we live in the first world and where children are dying in the third. Clean water is a human right. ::The Ghost Map via ::Amazon