Analyzing dozens of cases around the world yields some practical lessons. Generally, when you hear “water use” and “sustainability,” you expect those words to be followed by some bad news. Humanity’s enduring ability to ignore the math of declining water supplies is almost impressive. But there are cases where actions have successfully reversed our loss of water resources. A new paper in Science by Scott Jasechko of the University of California, Santa Barbara, examines documented cases of groundwater recovery around the world to identify which strategies have worked. Groundwater is invaluable for many reasons. For one, it’s (usually) cleaner than surface water. It’s also right under your feet and often close enough to the surface that it doesn’t take much energy to pump it up. And there’s loads of it down there, no matter the season. Because of this, humans use a lot of it for drinking water, agriculture, and every other use you can think of.…