Garden with Insight v1.0 Help: runoff

Runoff is water that falls on the soil during rainfall (or melts onto the soil during snowmelt), but cannot enter the soil (usually because the soil is already saturated with water), and so runs off the surface of the soil down a slope into a stream or gully.

Since the model from which this simulation was adapted (EPIC) was created largely to predict water erosion from runoff, the runoff portion of the simulation is complex (though this adaptation of it is not well tested). Basically runoff depends on how much water the soil already holds, several features of the soil including parameters that describe the soil surface, and the intensity of rainfall.