Area-based building (Water Overlay)

Area-based Buildings use polygonal geometry to apply effects across their entire surface area.

Examples of area-based buildings are the following hydraulic structures:

Icon	Name	Description
	Drainage	Expedited and conditional flow from the underground to a surface waterway.
	Inlet	Conditional flow from external area to inlet location. (If INLET_AREA is configured appropriately).

Building effects apply to any intersecting grid cell, treating it as fully contained within the building.