We can sometimes be extremely careless with how we treat water. This is astonishing because it is the most valuable resource on the planet. For all of us living in developed countries, it sometimes feels like there is a seemingly abundant supply of water. In truth, the Earth has a very small and limited supply of fresh water, and we must do everything in our power to protect it. A big step in making a difference is understanding what happens to the water we use, after we use it.