WastWa is an integrated system to treat leachate in situ, using several techniques powered by environmentally friendly energies.WastWa is a plant composed of specific designed solar stills, which are able to remove more than 50% of water and up to 98% of nitrogen (ammonia) from leachate. This process is powered only by solar energy, without chemical products or complex systems. The extracted water goes through a scrubber, the solution is acidified and the ammonium salts fall down. The treated water can be drained into waterways.The concentrate of leachate is used in a constructed wetland system. Through natural processes, utilized by plants, the concentrate of leachate is purify. At the end of the process, the output of WastWa is pure water dischargeable into waterways.