The document discusses water harvesting, which is the practice of capturing rainwater when it falls and storing it above or below ground to use later. Water harvesting has been used for centuries and provides drinking water, water for livestock, small irrigation, and replenishes groundwater. It can be practiced by capturing runoff from rooftops, local catchments, streams, and through watershed management. The benefits of water harvesting include providing water for drinking, irrigation, increasing groundwater, reducing floods and overloading of treatment plants.