Ecological sanitation: Principles, technologies and project examples for sustainable wastewater and excreta management

Abstract

In order to reach the UN Millennium Development Goals for significantly reducing the number of people without access to adequate sanitation, new holistic concepts are needed, focusing on economically feasible closed-loop ecological sanitation systems rather than on expensive end-of-pipe technologies, thus enabling all countries to finance and maintain sustainable sanitary systems. Such ecological sanitation systems advance a new philosophy of dealing with what to date has been considered as merely waste and wastewater. They are based on the systematic implementation of the reuse and recycling of nutrients, organics and water as a hygienically safe, closed-loop and holistic alternative to conventional solutions. Over the last few years an increasing number of pilot and demonstration ecosan projects have been implemented worldwide. These have contributed to the further development of a variety of ecosan technologies and operating and reuse options and have provided a large amount of experience with this new, holistic approach. In the following, the principles of ecological sanitation are presented, an overview on the range of ecosan technologies is given and several successful ecological sanitation projects are described.