Profile lines define profiles such as center lines or bank lines and can be either 2D or 3D. If they are defined as 3D then the z values that are a part of the geometry can be used to derive the bathymetric cross-section geometry. Profile lines are identified by a river and reach name and can be associated with cross-sections based on these names.
Figure 11 Profile Lines for Centerline and Banks
1.5.6