The first questions to be addressed, then, are what do we use water for, and where does it actually end up? Globally, and in most countries, the breakdown of water usage by sector is as follows: 70% for agriculture, 20% for industry, and 10% for household use. In short, we use the vast majority of our water for farming. Of that water, only a tiny fraction (seldom even as high as 5%) ends up in the actual plants; the rest evaporates, one way or another.