Hello,
As a follow-up to questions around errors in the overall model water balance I have the following observation:
If the options setting under the menu Options->Specific Option Settings->(E) Free surface(s) if "TOUCHING THE TOP SURFACE" is set to "Constrained" then if the "In(+)/out(-) flow on top" value is such that it causes the head to be constrained to the model top the budget imbalance reports the full value of recharge to the model (even though it is not being applied due to the constraint). This is clearly incorrect since the constrained option limits the quantity of recharge to prevent groundwater mounding above the top model layer.
This can be easily demonstrated by revising the option from "Constrained" to "Unconstrained" and observing that the imbalance is now close to zero for a steady-state model, as it should be.
I would consider this a bug in the software requiring a fix.
Regards,
Stephen Buck
