Although HEC-RAS will automatically list external boundaries, the user must specify internal locations where sediment boundary conditions are required. To add an internal boundary, press the Add Sediment Boundary Location(s) button, which will launch the river station selector depicted in the figure below. Select one or more of these river stations by double clicking on the list or selecting locations while holding down the control or shift button then pressing the arrow key. Remove cross sections from the selected locations list by double clicking on them or pressing the Clear Selected List button.
Chose sediment boundary conditions by selecting the row associated with the cross section. HEC-RAS will populate the sediment boundaries allowed at the selected node.
