Do-it-yourself greywater recycling systems have become a hot topic lately. What would normally be sent down the kitchen drain can be reused as a nutrient-rich irrigation system for urban farming. Some people go so far as to extend the concept to other human waste products, obviously with consideration of some important health implications.
The caption photo is of a water hyacinth, duckweed and papyrus pond in Austin Texas. Setups like this will typically filter waste sink water through a gravel bed into a small man-made wetland such as this.
Greywater recycling systems -- combined with a rainwater harvesting cistern on the roof and more advanced septic technology -- offers a peek at what future might look like for urban water systems. Water is a scarce and limited resource for most of the world, so while some of this stuff seems a bit crazy, you might end up needing to decide between that green lawn and your water disposal sensibilities.
The Greywater Guerrillas
See also:
Life in an earthship - way, way off the grid
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