Example 3: African Pivot with OptiSurface2D


This 69 hectare Centre Pivot on Greenfield Site, requires reliable surface water drainage to allow timely machine operations/access and less compaction particularly during harvesting.

Follow this dropbox link for the example survey file and unlocked osd file.

Existing Topography

Proposed Topography

Proposed Cut/Fill Map

Long Section

Cross Section


An OptiSurface2D design has been calculated to drain water in two directions away from the natural ridge that runs through the center of the field.  A special 'ridge' subzone, marked by red boundary, was used by the designer to define the alignment from which the water will run both ways.  Significant smoothing was applied in the main slope and the cross slope directions and maximum grades were limited to 2%.  This resulted in a smooth design with earthworks of 350 m3/ha (182 yd3/ac).  If the client wants to reduce earthworks by loosening the design constraints and reducing the smoothing can reduce the earthworks to 250 m3/ha (131 yd3/ac).

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