The river flow direction is defined by digitizing the river reach in a downstream direction. The software will display a flow directional arrow at the center of the river reach showing the assigned flow direction.
If the river reach is defined in an incorrect direction, either right-click on the river reach and select Reverse River Reach from the context menu or choose the Input | River Reaches | Reverse River Reach command. Selecting the Input | River Reaches | Reverse River Reach command will display the Reverse River Reach dialog box. This dialog box allows the user to optionally renumber the cross section river stations.