Hi Bijan,
the recharge to groundwater is not usually larger than infiltration, but this can happen.
Typically this is because the UZ is draining to the water table during periods of little or no infiltration.
In particular, the default initial conditions for the UZ is the saturation pressure curve up until it reaches field capacity, then the initial condition is field capacity above this. So, the initial condition for UZ is never less then field capacity.
Since the equilibrium water content is the actual saturation pressure curve, the UZ will drain during the initial simulation period, even if there is no rain.
Cheers and Happy New Year,
Douglas
