Model attributes (Water Overlay)

The Water Overlay's model calculations depend on a number of calculation-wide parameters. These parameters are available as attributes of the water overlay and can be modified as such.

Extended reconstruction (Water Overlay)

Partial start sec (water Overlay) Partial end sec (water Overlay)

Attribute	Unit	Range	Description	Default value
ALLOWED_WATER_INCREASE_M	m		The amount by which the water level on a water terrain must increase before it is considered stressed by water. This is used to compute the WATER_STRESS result type.	0.4
AVG_SHORE_WIDTH_M	m	0 to 10000 grid cells	With the surface water mode set to Grid Averaging, identified water average areas can be extended to include nearby shorelines within the configured distance.	3
AVG_TERRAIN_WIDTH_M	m	0 to 10000 grid cells	With the surface water mode set to Avg Terrain, identified water average areas can be extended to include surrounding terrain within the configured distance.	1000
AVG_TERRAIN_STORAGE_M	m	0 to 10000	When determining the water level of a land cell that will be averaged, the level will ignore the part that is reserved for storage.	0,05
BREACH_MEASUREMENT_DISTANCE_M	m		Distance from the breach area to the automatically placed measurement point for the downstream water level of the breach, in the direction of the breach.	100
BRIDGE_ELEVATION	nominal	0 to 2	Specifies the mode by which bridges are include in the elevation model, used for the water calculations.	Lowest
CULVERT_DEM_THRESHOLD_M	m	0 to 10000	The maximum distance a culvert's height can be below the terrain, for the terrain height to be adjusted to the threshold of the culvert.	10
DESIGN_FLOOD_ELEVATION_M	m		Buildings in the model are assumed to have at most this height compared to the surface of the terrain. Greater values can create a more accurate model but will impact performance.	1
GROUND_BOTTOM_DISTANCE_M	m	0 to 10000	Assumed distance under the surface terrain where the bottom boundary is situated.	10
GROUND_BOTTOM_PRESSURE_M	m		Optional: The additional head of higher areas outside the project causing water to flow in or out of the ground from deeper ground layers through the bottom boundary.	0
GROUND_WATER	nominal value		Whether and how water in the ground is simulated during the calculation.	Infiltration Only
GROUND_WATER_DEPTH_M	m	-10000 to 10000	The default depth of ground water in meters.	1
GROUND_WATERTABLE_WITH_SURFACE	boolean		Whether the ground watertable result type should also include the surface water level, when the groundwater levels are close to the surface.	True
HYDRAULIC_CONDUCTIVITY_WITH_THICKNESS	boolean		When selected, the Terrain value HYDRAULIC_CONDUCTIVITY_WITH_THICKNESS_MD is used for horizontal groundwater flow calculations, otherwise HYDRAULIC_CONDUCTIVITY_MD is used.	0
IMPACT_FLOOD_THRESHOLD_M	m		The amount of water a Building must experience before it is considered impacted by water.	0,1
IMPACT_RANGE_M	m		the width in meters of the water next to or against the building that have to be flooded before the building is considered impacted by water.	3
INCREASED_RESOLUTION	boolean		Load the DEM at twice the resolution.	False
INFILTRATION_FACTOR_S	factor	-10 to 10	This value is multiplied with the surface infiltration speed and can be used to adjust the infiltration over time. Default is 1 (no adjustment).	1
LIMIT_AREA	nominal value		Whether and how calculations in the simulation should be limited to specific locations of the project area.	0 (Entire map)
LIMIT_RAIN	nominal value		Whether rainfall can be overridden by rainfall defined in rain areas across the project area.	0 (Entire map)
MAX_INFILTRATION_M	m		Assumed maximum amount of infiltrated water that can be stored in the ground layer below non-water cells.	1
MAX_WATER_BOTTOM_M	m + datum		The maximum height for the bottoms of water terrains. Any water terrain with a bottom at a higher datum height has its bottom lowered to this value.	10000
MICRORELIEF_STORAGE_FRACTION	fraction (m/m)	0.0 to 1.0	Storage Fraction defines how much space is between Microrelief hills that can be used to store water. Setting this value to zero disables the Microrelief functionality all together.	1.0
MIN_MAX_ELEVATION	Nominal value	0 to 2	Whether to use highest and lowest elevations found for a grid cell for land and water respectively when interpreting the elevation model.	1
OBJECT_ENTRY_CORRECTION	cells	0 to 3 cells	How many cells allowed to move a hydraulic structure's entry point when it overlaps with another hydraulic building.	2
PREQUEL_SURFACE_LEVEL_RELATIVE	boolean		Whether the SURFACE_LEVEL prequel is considered relative instead of a datum height.	0
RISE_RATE_DISTANCE_M	m	0 to 10000	The water height threshold for computing the Flood rise rate result type.	1.5
SEWER_OVERFLOW_THRESHOLD	fraction (m/m)	0 to 1	How much of a sewer's storage must be filled with water before the sewer overflows are allowed to overflow water.	0.9
SHORELINE	Nominal value	0 to 2	Whether to automatically fill cells near a water terrain when there is a mismatch between the extend of the water terrain and the DEM.	1
DURATION_MIN_LEVEL_M	m	-10000 to 10000	The amount of water which must be exceeded in a specific location before the duration of surface water can be recorded. This is used to compute the SURFACE_DURATION result type.	0
STABILIZER_ANGLE	angle (0-90°)	0 to 90	A partly flooded cell (especially at the edges of waterways) can become unstable when the angles in X and Y direction are too far apart. In this case the fluxes in U and V cannot easily be resolved mathematically while preserving balance. To prevent unrealistic fluxes from appearing, only the flux in the primary direction will be preserved. A stabilizer angle of zero means that all cells can be considered partly flooded cells, while an angle of 90 degrees will disable the stabilizer.	10
START_DATE_MS	long		The date and time which is considered the starting moment of the simulation.	0
SURFACE_WATER	Nominal value		Whether and how water on the surface is simulated during the calculation.	Shallow
SURFACE_WATER_EVAPORATION_FACTOR	factor	0 to 10	The factor by which the weather evaporation factor is multiplied to compute the amount of evaporation which takes place on the surface.	1.3
TIMEFRAME_TIMES	integer	0 to	The time of individual timeframes in seconds relative to the start date of the simulation.	0
TIMEFRAMES	integer	1 to 1000	The number of intermediate results recorded during the calculation. Each timeframe becomes a snapshot of data which can be viewed and analysed.	10
UNSATURATED_FRACTION	fraction		The initial fraction of the maximum storage capacity of the unsaturated zone which is filled with water.	0.0
WEIR_DAM_MULTIPLIER	factor		The width with which the weir's dam should be generated perpendicular to it's direction, relative to its flow width.	4
WEIR_MOVE_INTERVAL_S	seconds	0 to 3.4028235E38	Interval between Weir height adjustments in seconds. The Weir moves up/down to reach the target upstream water level.	10
WEIR_MOVE_STEP_M	m		When the move interval has passed the Weir height is adjusted up/down by this step distance in meters.	0.01
WEIR_MOVE_RANGE_M	seconds	0 to 3.4028235E38	When the Weir height is adjusted up/down it is clamped by this value in meters.	0.5