Abstract: The invention relates to an irrigation and drainage device and/or water storage device, preferably for managing water, in particular irrigation of (green) areas and/or plants, comprising the following: at least one water-collection device (10, 20, 30, 40, 64) designed to collect and/or store water, wherein the water-collection device (10, 20, 30, 40, 64) is in direct or indirect fluid connection with a buffer (tank) (60) and/or a storage reservoir (80), wherein the buffer (tank) (60) and/or the storage reservoir (80) is/are designed to store water and to make the stored water available for use, for example to release it into an irrigation pipe network (85); at least one control unit (61, 130), which is designed to receive and/or acquire environmental data, in particular to acquire these data by means of at least one sensor (100), and based on the environmental data, using at least one actuator, for example a control valve (84), to make available for use a water volume flow from the buffer (tank) (60) and/o