The purpose of this tool is to show the paths of any overflows from catch basins or manholes, and the areas of ponding that will occur. The tool only asks you to select a terrain model that represents the surface, and appropriate feature definitions to define the symbology of the pond and path graphics.

For a road design, the terrain model you select would normally be a complex, that is made up of both the proposed surface and the existing surface that surrounds it. If you are analysing how an existing drainage system will cope with more inflow, then the terrain model might just be that of the existing surface.

The results shown include a column for Overflow Volume, and a row for each Catch Basin or Manhole. these volumes are then routed across the selected terrain model, using the XYZ coordinates of the node, to show the effect of the overflows.