Inferring ground elevation from surrounding elements

Product(s): SewerGEMS, SewerCAD, StormCAD, CivilStorm, WaterGEMS, WaterCAD
Area: Layout and Data Input


If there are missing node elevations but I do not have access to terrain data, can the missing elevations be inferred from nearby nodes that do have elevations?

Can missing elevations be inferred from surrounding nodes?


Currently this can be accomplished with the following workaround. In summary, you can export nodes with elevations to shapefile format, then populate the nodes with missing elevations using that Shapefile in Trex.

1) Create a selection set of the nodes that have missing ground elevations that you would like to fix

2) Create a new hydraulic-model flextable for your main node type of interest, such as manholes for SewerGEMS and SewerCAD, or junctions for WaterCAD or WaterGEMS (View > Flextables > right click "tables - hydraulic model" > new). Choose only the label and the ground elevation field.

3) Filter the flextable so that it only contains the nodes that have good ground elevations. This can be accomplished using a filter on ground elevation for example.

4) Click the button in the upper-left corner of the flextable and choose to export to Shapefile.

5) Repeat steps 1 and 2 if you have a significant number of other element types in the area of the nodes with missing elevations (such as hydrants, and tanks for the Water products or catchbasins and transitions for the storm and sewer products), then combine them together into a single shapefile in an application such as ArcMap.

6) Open the Terrain Extractor (Trex) tool, choose Shapefile as the data source type, select the shapefile from above, select the ground elevation field, select the selection set from step 1 (so that it only updates the nodes with the "bad" elevations) then complete the steps to interpolate the ground elevations.

Related Enhancement # 816174