The extraction of the parameters relies on the way the levee is
outline from the continuum of the terrain and of the LiDAR data. To
delimitate the levee slope, a criteria of 5% slope for flat areas was chosen.
The 5% slope threshold was selected after evaluating the topography
of the levees within the reach. Once levees were demarcated
using a derivative approach to the DGM, the crown area within the
fore and back slopes was demarcated, again using the 5% slope criteria,
assuming the crown is flat up to the start of a slope, defined as
a 5%. To define the slopes, the selected method consists of the gradient
of the line which was fit from the hinge point in the crown to
the toe of the levee. Other criteria were considered such as the median
slope values obtained in the profile, this method would be interesting,
given that it captures information about the roughness of
the terrain in the profile, but we selected a traditional engineering
surveying method to compare the slope values against the design
standards.