Dear all, I'm currently dealing with a MODFLOW simulation where the head of an unconfined aquifer changes in time. The assumption is that for a given time and in correspondence of the channel network, the head of the aquifer stays dz meters below the surface. In order to impose suitable boundary conditions, I created a TIN based on the GMS grid (i.e. the two coincide) and I let the TIN have different time step (in order to do this I first exported the TIN, modified it adding nt columns that account for the distance dz of the aquifer from the surface, where nt is the number of time step conside