Result type (Water Overlay)

The water model performs complex calculations, and multiple types of results can be provided. In principle, each overlay can be configured to display a single result type.

Result types can differ in the kind of data they display, the layer (surface or underground) of which they display that information, and how that data is recorded. Different result types can monitor data in the following ways:

• Start: The data is determined at the start of the simulation, and does not change afterwards.
• Last: The data is the latest value determined at the timestep the data is recorded. The values can increase and decrease between different timesteps. This mode is primarily used for monitoring progression.
• Maximum: The data is the highest value determined up until the timestep the data is recorded. The values can only increase or stay the same, but will never decrease. This mode is primarily used to gain insight into impact; the most severe situation any point had to endure.
• Total: The result of a running tally, counting the relevant data up until the timestep the data is recorded. The value can only increase or stay the same, but will never decrease. This mode is primarily used to gain insight into quantities rather than duration.

List of Result Types

Result type	Unit	Display mode	Description
BASE_TYPES	Nominal value	Start	Categorization of the individual cells based on how they are processed by the water model, displaying which cells are considered to be specific features.
DEBUG_UV
DEBUG_WALLS
EVAPORATED	m (mm)¹	Total	The amount of water that has evaporated. The value is the sum of the quantities evaporated from the surface and the underground.
GPU_OVERVIEW	nominal integer	Maximum	Shows which GPU cluster calculated which part of the overlay.
GROUND_LAST_STORAGE	m (mm)¹	Last	The (effective) amount of water in the underground unsaturated zone.
GROUND_LAST_VALUE	m (mm)¹	Last	The distance between the surface and the groundwater level.
GROUND_MAX_STORAGE	m (mm)¹	Maximum	The (effective) amount of water in the underground unsaturated zone.
GROUND_MAX_VALUE	m (mm)¹	Maximum	The distance between the surface and the groundwater level.
GROUND WATERTABLE	m + datum	Last	The groundwater level, relative to datum.
IMPACTED_BUILDINGS	nominal integer	Maximum	Constructions impacted by excess water.
SEWER_LAST_VALUE	m (mm)¹	Last	The amount of water stored in the sewer.
SEWER_MAX_VALUE	m (mm)¹	Maximum	The amount of water stored in the sewer.
SUBSTANCE_A	x/m²	Last	The amount of substance A present. The value is the sum of the quantities on the surface, and in the underground.
SUBSTANCE_B	x/m²	Last	The amount of substance B present. The value is the sum of the quantities on the surface, and in the underground.
SUBSTANCE_C	x/m²	Last	The amount of substance C present. The value is the sum of the quantities on the surface, and in the underground.
SUBSTANCE_D	x/m²	Last	The amount of substance D present. The value is the sum of the quantities on the surface, and in the underground.
SURFACE_DIRECTION	geo angle (0-360°)	Last	The direction in which water is flowing across the surface.
SURFACE_DURATION	s (min)¹	Total	The amount of time the water depth on the surface exceeds SHOW_DURATION_FLOOD_LEVEL_M.
SURFACE_ELEVATION	m + datum	Start	The rasterized version of the terrain height for use in the water overlay's calculations.
SURFACE_FLOW	m³/m²	Last	The amount of water which has flowed through a given location.
SURFACE_LAS_SPEED	m/s	Last	The (horizontal) speed of water flow in any given location.
SURFACE_LAST_VALUE	m (mm)¹	Last	The amount of water on the surface.
SURFACE_MAX_SPEED	m/s	Maximum	The (horizontal) speed of water flow in any given location.
SURFACE_MAX_VALUE	m (mm)¹	Maximum	The amount of water on the surface.
WATER_STRESS	m (mm)¹	Maximum	The amount of water on the surface, similar to SURFACE_MAX_VALUE. However, for water terrains, the water level must rise by at least ALLOWED_WATER_INCREASE_M. Otherwise, the reported value in those locations is 0.

¹ the units between () are as displayed in the 3D client. If exported to GeoTiff the SI-convention is used: meters (m) and seconds (s).

Each result type would consist of a unique output of data after a calculation, and is accompanied by its own legend. When the result type of the overlay is changed, the legend is updated automatically, but the data may not be recalculated automatically. This may result in the visual output of the overlay changing, because the unchanged data is displayed with a new legend. When changing the result type, it is recommended to force a recalculation of the overlay before interpreting the output.

Result child overlays

Each overlay can only display a single result type. When using a water overlay, it is conceivable that multiple result types are relevant to a project's use case. It's possible to duplicate the overlay, and set the copy of the overlay to a different result type, but this is not recommended. Downsides of this approach are that the simulation has to run in full multiple times, causing a severe increase in calculation time, and that when changes to the overlay's configuration have to be made those changes need to be made to all water overlays.

It is possible to add result child overlays overlays to a water overlay, which can display different results coming forth from the same calculation. The advantages of using result child overlays are that for any given water overlay, the calculation of the overlay only occurs once, rather than multiple times equal to the amount of desired result types. Additionally, the configuration for the calculation is only defined in a single overlay, which makes it easier to make sure all results come forth from the exact same simulation.

Result child overlays do not recalculate if either they or their parent is set to inactive.

If a calculation overlay is removed, all result child overlays of that overlay are removed as well. Separate overlays set as child overlays (such as input overlay) of the overlay will not be removed.

It is only possible to add result child overlays via the configuration wizard, in the output overlays step.