Oh really? LOL In 1980 Kyoto Japan (one of Japan's largest cities) about 40% of the people who lived there used a privately owned (modern high tech) privy vault. Why? Well, to quote YOU: standard economics. It's cheaper to own and maintain your own privy vault when compared to the cost burden to run a public sewer system (which also wastes a ton of water). World Bank Article: John M. Kalbermatten, DeAnne S. Julius, and Charles G. Gunnerson. "Appropriate Technology; Water Supply and Sanitation; Technical and Economic Options" (pdf), World Bank, December 1980, referenced 2013-01-16. Mises comment here: According to a 1980 study produced for the World Bank, only about 34 percent of the total Japanese population have sewers, while an even higher percentage rely on a highly modernized version of the privy vault (which includes a system of vacuum trucks). The authors chose Kyoto as their case study, a city where privy vaults serve 40 percent of the population, while another 40 percent use conventional sewers. They contend that privy vaults in Kyoto have several notable advantages. First, they are cheaper to run. This is because they have lower recurrent costs (or day-to-day costs) than sewers. Indeed, low recurrent costs have been invariably portrayed as the raison d'etre of sewers. Sewers, as the quintessential capital-intensive technology, were supposed to essentially run themselves. Sewers generate a whole set of recurrent costs, including consumption of large quantities of water, an increasingly expensive commodity. A second recurrent cost is the costly treatment plants needed by the average sewer system. The authors calculated that if added together, all these recurrent costs make sewers more than twice as expensive as privy vaults. Privy vaults also do not produce nearly as much water pollution as sewers, and in fact, from a public health standpoint, are equally safe. The Japanese example reveals that existing technologies can with some improvements be made entirely compatible with urbanization, industrialization, and environmental protection. Moreover, the authors point out that, unlike privy vaults, centralized sewer systems require massive investment costs not only to built but also to maintain. --o-- This is my comment, as I have said in the past, IF it is not possible to organize large groups of humans without initiating violence against morally innocent people - then we don't have those organizations. IOWs, if we can only maintain a city about the size of Kyoto - THEN THAT'S THE LIMIT. What's so hard to get here? We don't 'NEED' to live in Megacities. And if it requires human Slavery to do so, then we don't. Think you can agree to that much? Please Register or Log in to view the hidden image!