August 2019—It’s no secret that humans have been over-pumping groundwater to the point of cities sinking. In many of the major agricultural areas, farmers have to drill deeper and deeper as the water table falls. So what if we could put water back into the aquifer, especially during heavy rain years or flooding? This practice is becoming increasingly common. You can do it naturally, for example with check dams and by letting rivers flood into wetlands, or by actively pumping the water back down. This article does a nice job of explaining how it works and the concerns to be aware of.