An optimal design method is presented for dewatering a excavation site. It predicts the optimum number of deep wells, their locations, and the rate of pumping needed to maintain ground water levels below specified elevations at steady and unsteady state. In our proposed method a linear programming method is used to determine the pumping rate at steady state and AIC is used to suggest the optimum deep well locations. This is accomplished by including the finite element analysis of two-dimensional steady seepage flow. Nonlinear least-squares algorithm incorporating finite element analysis of unsteady seepage flow is used to compute the pumping rate required to reach ground water levels below appointed elevation in a prescribed time. The method is applied to several examples of dewatering for a large excavation site in unconfined aquifer models.