Elevating Objects

A grid surface model in this context is usually a representation of the terrain surface, including the surface beneath features like buildings etc. Without taking measures to correct this, some drainage lines can take its path through these objects.

Example: Drainage lines going through buildings

To force drainage lines around objects like buildings, we use the Elevate option by defining a polygon around the object. All grid points inside the polygon will be elevated from the surface, thus avoiding water from running though this area.

Example: Drainage lines going around elevated buildings

Note: The function only accepts closed polygons as input. 

Note: Under Settings one can filter away objects with small areas. The setting has it's primary use to exclude small sized buildings that are insignificant to the analysis. This will also help improve on the overall calculation speed.

Tip: The function can be used on any object, not only buildings, to avoid drainage lines from passing through and taking another path.