Simulation of Horizontal and Vertical Drainage Systems to Combat Waterlogging Problems along the Rohri Canal in Khairpur District, Pakistan

Abstract

Continuous seepage from earthen canals creates a serious water-management problem in Pakistan. Efficient water management through a properly designed drainage system is therefore indispensable and imperative not only for the control of waterlogging, but also to provide a favorable environment for crop root development that ultimately enhances crop growth and increases yield potential. This paper discusses the effectiveness of different remedial measures adopted to intercept seepage from the Rohri canal and control the rising water table on 1,000 ha of agricultural land near the Gambat railway station in the district of Khairpur in the Sindh Province of Pakistan. A three-dimensional (3D) finite-element model for groundwater flow and solute transport (FEMGWST), developed at Universiti Putra Malaysia, has been used to evaluate the performance of horizontal and vertical drainage systems, operating either independently or simultaneously, for different flow levels in the Rohri canal. Simulation results have revealed that an increase in tube-well discharge from 20 to