Evaluating the Effectiveness of Curtain Wells Against Subsurface Flooding in Yuma, Arizona

Abstract

During 1983 the Colorado River experienced high flow conditions due to abnormally high snowmelt and runoff from the upper basin states. Flood stages provided sufficient hydraulic head to force water under the protective levee system around Yuma, Arizona. This caused inundation of adjacent urban and agricultural lands from the subsequent rise in the local water table. A methodology was planned whereby a series of "curtain wells" would be installed and the water table pumped down to below grade conditions. The feasibility of accomplishing this was studied by retrofitting an existing agricultural well located on "Yuma Island", and installing a series of monitor wells in a two-dimensional array perpendicular and tangential to the levee. The production well was pumped continuously for eight weeks, and the subsequent drawdown within the piezometers monitored. Based on the data gathered, it was possible to predict the effectiveness of the proposed curtain well system.