Hi, I would like to simulate local outflow/discharge from my groundwater system. The outflow has a specific reference elevation (m). The outflow volume [Q] (l/s) should be modelled dynamic according to the simulated head [H] as follows:   H(1): 0.01, Q(1): 1 l/s H(2): 0.05, Q(2): 17 l/s H(3): 0.10, Q(3): 47 l/s H(4): 0.15, Q(4): 86 l/s H(5): 0.20, Q(5): 132 l/s For example, if the simulated head is 0,10 m, 47 l/s should be removed from the system. So far, I have applied a Head BC using a min. and max. flow-rate constraint. However, this approach only allows for specifying one discharger rate (although I want to express several discharge rates according to the above head-discharge relationship). So: how can I simulate the removal of groundwater at a given location according to the above relationship?