overlandflow
Overland flow, or surface runoff, is water that moves over the land surface during rainfall or snowmelt without infiltrating into the soil or entering a stream immediately. It occurs when the rainfall rate or duration exceeds the soil’s infiltration capacity, or when the soil is saturated. The water can travel as sheet flow and may concentrate into small channels.
Two main mechanisms generate overland flow. Infiltration-excess runoff (Hortonian) happens when rainfall exceeds the soil’s infiltration
Factors influencing overland flow include soil infiltration rate, antecedent moisture, rainfall characteristics, land cover and management,
Overland flow affects hydrology by contributing to flood peaks, sediment and pollutant transport, and erosion. It
Measurement and modeling of overland flow rely on rainfall–runoff relationships, infiltration models, and surface routing. Velocity
Management approaches aim to reduce adverse effects by promoting infiltration and reducing peak discharge. Techniques include