Greywater
This site, hosted by a single individual, contains everything you want to know about greywater, including scientific information about the nature of greywater, a thorough scoping of many technologies available to deal with it, a series of case studies and a methodology for planning a grewater management system. It includes many diagrams and pictures that are easy to understand.
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Home Use of Greywater, Rainwater Conserves Water
This site, hosted by the Water Resources Research Centre at the University of Arizona, explores many aspects of water and graywater, providing an easy to read summary of most issues along with examples and facts.
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SustainableBuilding Sourcebook: Guidelines
This site is part of the excellent Austin Green Builder Program and covers many facts and numerous methods of dealing with greywater through various technologies, including design diagrams.
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