fix(MFsetupMixin.setup_sfr): properly handle revised SFRmaker assign_…

…layers method that returns a 3D array of revised cell bottom elevations, when there are reaches that extend below the model bottom. In cases where there are multiple inactive layers below the lowest active cell, multiple bottom layer elevations will need to be revised.

mfsetup/mfmodel.py

@@ -1530,28 +1530,21 @@ def setup_sfr(self, **kwargs):
                                          idomain=idomain)
         sfr.reach_data['k'] = layers
         if new_botm is not None:
-            if self.cfg['intermediate_data'].get('botm') is None:
-                f = os.path.normpath(os.path.join(self.model_ws,
-                                                  self.external_path,
-                                                  self.cfg['dis']['botm_filename_fmt'].format(self.nlay - 1)
-                                                  ))
-            else:
-                f = self.cfg['intermediate_data']['botm'][-1]
-            save_array(f, new_botm, fmt='%.2f')
-            print('(new model botm after assigning SFR reaches to layers)')
-            botm[-1] = new_botm
             # run thru setup_array so that DIS input remains open/close
             self._setup_array('dis', 'botm',
-                              data={i: arr for i, arr in enumerate(botm)},
+                              data={i: arr for i, arr in enumerate(new_botm)},
                               datatype='array3d', write_fmt='%.2f', dtype=int)
-            # reset the bottom array
-            # is this necessary?
-            self.dis.botm = botm
+            # reset the bottom array in flopy (and in memory)
+            # is this necessary? =
+            self.dis.botm = new_botm
             # set bottom array to external files
             if self.version == 'mf6':
                 self.dis.botm = self.cfg['dis']['griddata']['botm']
             else:
                 self.dis.botm = self.cfg['dis']['botm']
+            print('\nModel cell bottom elevations adjusted after assigning '
+                  'SFR reaches to layers\n(to accommodate SFR reach bottoms '
+                  'below the previous model bottom)\n')
 
         # option to convert reaches to the River Package
         if self.cfg['sfr'].get('to_riv'):