Using USGS Program WTAQ and Superposition to Model Stream Depletions

Abstract Concerns about streamflow depletions due to groundwater pumping have stimulated the development of various analytical and numerical approaches to quantifying such depletions. Absent among the analytical approaches are those applicable to problems involving a three‐dimensional aquifer with a partially penetrating production well. The U.S. Geological Survey program WTAQ can be used to simulate water‐level declines in a three‐dimensional aquifer without a stream. However, by applying the principles of superposition, WTAQ is used to simulate temporal streamflow depletions due to pumping from a partially penetrating well in a homogeneous, three‐dimensional, horizontally infinite, water‐table aquifer with an arbitrarily located infinitesimally thin stream positioned vertically at the water table.