Influence of the location of production wells in unconfined groundwater basins: an analysis by numerical simulation

Transitional basin yield (TBY) is the net cumulative inflow of water into the system, induced by and during development at a particular site, from an initial to a final steady-state condition. Sustainable basin yield (SBY) on the other hand, is the amount of water captured from precipitation due to production at a particular site under the newly established steady-state conditions. TBY is highest for well locations in the discharge area and decreases gradually as the sites are moved toward the recharge area. This is so because more of the naturally discharging, and thus otherwise lost, water is captured by wells located in discharge areas than by wells in recharge areas. On the other hand, SBY is greater if the wells are located in recharge areas than if they are in the discharge areas because an increasing percentage of precipitation is converted to infiltration by production wells as their locations are moved upslope in the basin. From a regional hydrological viewpoint, these are key relations in optimizing the development potential of the groundwater resources in extensive unconfined basins. -from Authors