Numerical modeling of dewatering system to construct pump basins in open sea water intake system by MODFLOW

Pump basins are important structures in open sea water intakes. Dewatering construction site of these structures with no leakage inside the site is an essential issue. Throughout this paper, two common aspects of dewatering systems, namely big wells and well points are evaluated to make the construction site of the pump basin ready at the intake system of Bushehr desalination installations. To achieve this, MODFLOW software was employed to model the dewatering systems with results demonstrating the performance of the considered dewatering methods. According to the observed results, to have an efficient dewatering system, a number of about 26 wells as high capacity ones (well discharges ranging from 0.5 to 5.5 lit/s)are needed vs. 119 well points (well discharges ranging from 0.1 to 1.1 lit/s). In addition, sensitivity analysis of the system, as regards the variation of soil conductivity (in both space and time) proves that the well point system is more efficient than the high capacity well system, for dewatering an uncertain site.