My proposal attacks the water use reduction (3rd category). It promotes to use less water, or use it properly. (for the plants for example)

I am designing a device to actually collects the cold water from showers. Before the warm water comes along, the cold water is wasted. With a device designed for this (no buckets, but something that offers a added value) we can use this water for anything: is totally clean and usable!

Buildings covered: Existing schools, hospitals and apartments complexes.