Yes, it is a steady-state simulation. Am I right in assuming that
steady-state simulation means that water levels are calculated for a
quasi infinite time span? Or do my settings for start and end times in
VisualModflow influence steady-state calculation?

Although I considered 1 mm/a of recharge quite a low value it seems it
is far too high for a aquitard of say k=1e-8. Can someone point me to
the formula that calculates the recharge that an aquitard of k=1e-8 can
take?

Anyway - in my model I have a quaternary layer on top of the aquitard.
Where the aquitard crops out I initially changed the k-value of the top
layer to that of the aquitard. I will reset this to a reasonable value
that allows lateral runoff in the quaternary layer.

Dieter


Stela Cota schrieb:
> Because you are probably talking about a steady-state simulation, isn´t it?
> I had a problem like this too. If the K is too low, the porous material is
> not able to conduct the water to the boundary conditions and it just can
> accumulate, rising the water level. What happens in this case is that water
> will be removed by runoff and will not infiltrate in the soil. But I agree
> that it seems a little strange not being able to infiltrate any water at
> all?
>
> Stela.
>
>
> 2008/8/25 Dieter Plass <plass@...>
>
>
>> It seems I am lacking some basic understanding of hydraulics: Why does 1
>>
>> mm/a of recharge to an aquitard result in a water level rise of 1.000 m?
>>
>> Dieter