Gray water is tricky to deal with. On the one hand, it is wasteful to send it back into the sewer systems along with the truly polluted waters found there. On the other hand, it cannot be drunk or used to bathe or shower without some process of filtration.
Like a self-contained interior ecosystem, this wonderful green shower design by Jun Yasumoto incorporates aesthetically pleasing natural elements that grow around you but also contains a series of systems that slowly recycle your waste water into fresh, usable and fully drinkable H2O.
A series of organic plant materials slowly filter the larger elements from the water and the fine-tuned filtering takes place in carbon-activated filters below your feet. At the end of the cycle the water is good as new and the plants grow from the organic materials they catch.