Surface water (SW) is linked to groundwater (GW) through myriad connections. Hydrological scientists from ancient times were aware of the water cycle concept, but not until the end of the twentieth century did the scale and dramatic eects of anthropogenic activity force scientists, engineers, and water users to start managing SW and GW within a water budget framework as a single resource (Winter et al., 1998; Healy et al., 2007).
