Overland Flow - Technical Reference

When the net inflow of water onto the cell (eg rainfall or runofff to the cell) exceeds the infiltration capacity of the soil, water ponds on the ground sur­face. This water is available as surface runoff, to be routed downhill towards the river system. The exact route and quantity is determined by the topogra­phy and flow resistance, as well as the losses due to evaporation and infiltra­tion along the flow path.

The water flow on the ground surface is calculated by MIKE SHE’s Overland Flow Module, using the diffusive wave approximation of the Saint Venant equations, or using a semi-distributed approach based on the Mannings equation. Alternatively ponded water can be routed directly to a river, bound­ary or internal depression using the OL Drainage function.

This chapter is the technical reference for the Overland Flow Module in MIKE SHE.