Sewage water is a complex mixture in terms of chemical, biological and physical characteristics. It is part of the most renewable wastewaters while it should not be, at least in arid and semiarid countries. A trigonal problem of aridity, increasing population together with mismanagement of natural resources are combined in many areas of the world, predominantly in the southern hemisphere that is politically referred to as developing countries. Increasing population per se imposes the adoption of new strategies for handling waste water including sewage water more efficiently, especially when combined with shortage of food resources. Green areas not only provide crops for food and fodder but also enrich the global atmosphere with oxygen. Plants also absorb oxides of carbon, nitrogen and sulfur (COX, NX and SX; respectively), thus cleaning the atmosphere and turn it healthier. Subsequently, greening any area on earth by cultivating any kind of green cell must be of global concern, not left as a national activity only.