Cross Sections

Cross sections for a simplified dam-break analysis must be defined in a 1D-Hydraulic Cross Section coverage. A minimum of two cross sections are required (upstream and downstream ends of the river to be modeled), but sufficient cross sections to define the floodplain should be included. If you are using a digital terrain model to extract cross sections then it is fairly simple to include additional cross sections without the requirement of a field survey.

SMPDBK uses a table of top-widths corresponding to incremental elevations to define the cross sections. WMS will compute 8 incremental depths automatically for each cross section since this is the maximum number of increments allowed by SMPDBK. The eight increments are equal and determined based on the low and high elevations of the cross section. Manning's roughness values can be determined for segments of the cross section based on an area property coverage.