The aim of the modelling studies was to quantify the effect of empolderment and controlled drainage on the project area and selected adjacent areas. Changes relating to the depth, area and duration of flooding in the pre-and post-project condition were studied in particular.

The model setup for the project was based on previously established Atrai submodel which covers the Atrai-Baral-Sibbarnai river systems. All major drainage routes within the project area including existing structures and flood cells were incorporated in the Atrai submodel to develop a very detail model of the project and adjacent areas. Model simulations covered generation of data on changes in flooded areas and flood duration in the pre- and post-project conditions, generation of period depth maps, and simulated water levels in adjacent areas.

The use of a mathematical model to obtain an insight into the effects of flood protection and drainage schemes have been successfully demonstrated in this project. However, recently introduced GIS technology at SWMC will provide more suitable basis for the spatial interpretation of such investigations.

The modelling was carried out alongside the North West Region Modelling activities of the Surface Water Simulation Modelling Programme, Phase-II. The model was calibrated and verified for the period of 1990 to 1992.