Hydrological attributes of buildings (Water Overlay)

Besides the buildings which directly influence the hydrologic model as a hydraulic structure, each construction may also have attributes which can contribute to the hydrological model in some way. These attributes are stored and used on a grid cell level. This is different from the hydraulic structure attributes, which are stored and used on an object level.

These attributes can be changed individually per construction or per construction's function. In most cases, these attributes already exist as a function value.

Icon	Attribute	Unit	Range	Description
	GROUND_INFILTRATION_MD	m/day		The speed at which water can flow vertically from the surface to the unsaturated zone.
	SEWERED	boolean		Whether this building is connected to the sewer.
	WATER_STORAGE	m³/m²		The amount of water this building can store.
	ROOT_DEPTH_M	m	0 to 65519	The depth of the roots of this Building, relative to the terrain height at the location of this Building. Water can be drawn from the ground and evaporated if the roots can reach it.
	WATER_EVAPORATION_FACTOR	factor	0 to 65519	Factor indicating how much a building with a crop, tree or plant function facilitates evapotranspiration. This factor is multiplied with the weather's evaporation rate at a particular time in the simulation.
	FLOOR_HEIGHT_M	m		The height of a floor in a building. Additionally each section of a building can have a different amount of floors.
	CRITICAL_INFRASTRUCTURE	nominal		Whether this building is deemed a critical. 0 means the building is never deemed impacted.
	WATER_MANNING	s/(m1/3)	0.01 to 0.255	The Gauckler–Manning coefficient of the building.
	TRACER_A	x/m²/s	-3.4028235E38 to 3.4028235E38	The amount of tracer A created per second per m² in this location.
	TRACER_B	x/m²/s	-3.4028235E38 to 3.4028235E38	The amount of tracer B created per second per m² in this location.
	TRACER_C	x/m²/s	-3.4028235E38 to 3.4028235E38	The amount of tracer C created per second per m² in this location.
	TRACER_D	x/m²/s	-3.4028235E38 to 3.4028235E38	The amount of tracer D created per second per m² in this location.

In addition to the Attributes of Buildings affecting the calculations of the Water Overlay, the building height of Buildings affects the interpretation of the elevation model.

Notes

• In contrast with hydraulic structures, which can only behave as a single hydraulic object, buildings can have all of the above effects on the hydrological model simultaneously.
• Attributes which are connected to a function value can not be redefined using a different attribute name.