Polygons

Polygons provide a method for specifying a geographical area on the GeoPlan Window. You can use polygons:

• as a bounding polygon when generating subcatchment boundaries using Thiessen polygons
• to define areas of a Ground Model in which height correction is required
• to represent voids when generating a 2D mesh
• to define areas (spatial rain zones) within the network to which spatial rainfall will be applied when using spatial time series databases
• to specify spatial rain sources to be applied to spatial rain zones during simulation, as well as the order in which they should be used

Polygon Categories

A Polygon may be associated with a polygon category. Polygon categories can be used to group sets of polygons in the network. They can be used to:

• Identify a set of polygons on the GeoPlan Window by use of a polygon theme on the Category ID field
• Identify polygons to be used as Impermeable Area Surface data for Surface Area Take-Off (InfoWorks networks only)
• Identify polygons to be used as voids when creating a mesh for 2D modelling
• Identify the spatial rain source type, e.g. associated data stream

To assign a polygon to a category, type the name of the category into the Category field of the polygon on the Polygons Grid window or Property Sheet.