RSP21

Hi All, I have created a few drain coverages, when I map these coverages to MODFLOW, one stress period before that defined in the original coverage becomes active as a drain. For example, in the screenshot below in the coverage I define the beginning of drainage at timestep 61 (as indicated by a conductance value of 1). However, when examining sink/sources for cells defined as a drain using that coverage, the timestep prior to the one defined in the coverage becomes active and is given a conductance value ~ half of that given to other stress periods as shown in figure below: The final drainage timestep in the coverage is correctly defined as the final drainage timestep once mapped, however it too is given a conductance value ~half of that given in the interim stress periods. Could someone please advise what is happening here, and whether it is possible to have a consistent conductance value assigned to the timesteps originally defined in the coverage?

Hi, I have the same problem. My MODFLOW-USG model is running with certain horizontal and vertical hydraulic conductivity values. However, if I changed the horizontal and vertical K, the model wont converge as a results of dry cells. I am using '(1) Newton with Delta-Bar-Delta' with layer types of 'Convertible' in the LPF Package options (the model wont converge by selecting the 'Convertible Upstream' option). I also using the latest version of MODFLOW. Any advice is greatly appreciated.

Hi, I have the same issue to define the bottom elevation of drains (the TIN and Raster aren’t good to define the drain elevation). When I map the drain coverage to MODFLOW, drain elevations always place below the cell bottom elevation. I have a set of drains defined with arcs in layer 1 (top layer) and with polygons in layer 3. I am using the MODFLOW USG and unstructured grid (UGrid). I tried the 'Seepage Face' instead of 'Drain'. However, I am getting this error: “The seepage face type requires a stacked grid. It requires a UGrid with horizontally identical layer (IVSD=-1).” Does anyone know how to solve this issue?