WHAT IS INFILTRATION
When water falls on a given formation, a small part of it is, first of all, absorbed by the top thin layer of soil, so as to replenish the soil moisture deficiency. Thereafter, any excess water moves downward where it is trapped in the voids and becomes groundwater. This process, whereby, water enters the surface strata of the soil and moves downward, towards the water table, is called infiltration.
The actual prevailing rate at which water enters the given soil at any given time is called the infiltration rate.
The maximum rate at which soil in any given condition is capable of absorbing water is called its infiltration capacity.