Relation of Shape of Artificial Recharge Pits to Infiltration Rate

Abstract

This article discusses a study comparing a wedge‐shaped recharge pit to a rectangular pit to determine why water infiltrates the side area of a recharge pit at a greater rate than the bottom area. A pair of two‐dimensional hydraulic models were constructed that were analogous to the subsurface conditions surrounding recharge pits. The two models were alike in every respect except for the shape of the recharge pit centered at the top of each model. The medium in both models was identical as to permeability, porosity, and other hydrologic characteristics. During recharge tests, the flow discharged into the bottom of the tanks at each side of the model. Therefore, the hydraulic head difference between the recharge pit and the discharge points in the end tanks should have been the same in both models. Although the hypothesis appears to have been valid, the measured difference in performance between the two pit shapes was not great enough to establish the superiority of the wedge‐shaped pit over the rectangular pit.