Field application of DRAINMOD model to the simulation of water table, surface runoff and subsurface drainage

Artificial drainage engineering is necessary to prevent the waterlogging disaster, promote the crop growth and ameliorate the farm tillage management. A properly designed drainage system ensures the good operation for drainage system and a suitable environment for plant growth. Based on water balance, DRAINMOD was developed to predict the impact of drainage system on crop growth and hydrology. The model is suitable for shallow water table and relatively humid regions. This paper described the basic theory of model and parameter input requirement. The field data were collected from conventional drainage and controlled drainage/subirrigation plots at Eugene F. Whelan, Woodslee, Ontario, Canada, from 1992 to 1994. The model performance was evaluated by graphical display and statistical indexes. The simulated daily water table during June and August every year, cumulative surface runoff and subsurface drainage from 1992 to 1994 were compared with measured values. The results show that the simulated values were in good agreement with measured values. The model has a good simulation performance for hydrology and can be a useful tool for the design of the drainage system and farm water management.