Seepage Face Modeling for Large-Diameter Well in Unconfined Aquifer

Abstract

Modeling of the seepage face in the case of flow toward wells has received considerable attention in the literature. It is evident from the literature that the models applicable to describe the well loss in the confined flow situation have been also employed to represent the seepage face variation in the case of unconfined flow situations. It is only during the past decade that attempts have been made to describe the seepage face in the case of wells located in an unconfined aquifer. In these studies, the seepage face has been related to the aquifer discharge, the duration of pumping test, the time since the start of pumping, etc. With a view to further simplifying the existing seepage face models, the present study approaches the problem of seepage face modeling in the case of a large-diameter well located in an unconfined aquifer using the velocity of flow at the well face. The resulting expression of the seepage face is not only simpler but also converts to the existing seepage face models, or their simplified forms, as a particular case.