Prequels (Water Overlay)

Prequel overlays can be linked to the Water Overlay to initiate particular parts of the model with more accuracy and detail. They can even be used to link result types of one Water Overlay as prequel input to another.

Name	Prequel	Underlying data	Unit	Range	No data	Description
Terrain elevation	TERRAIN_ELEVATION	Water Prequel	m datum	-10000 to 10000	Clamped to range	Used for initializing the terrain elevation on this datum.
Surface level	SURFACE_LEVEL	Water Prequel	m	-10000 to 10000	Clamped to range	Used for initializing the surface water level on this datum, both in waterways and on land.
Groundwater depth	GROUND_WATER_DEPTH	Water Prequel	m	0 10000	Clamped to range	Used for initializing the ground water level to these depths.
Groundwater datum	GROUND_WATER_DATUM	Water Prequel	m datum	-10000 10000	Clamped to range	Used for initializing the ground water level on this datum.
Unsaturated fraction	UNSATURATED_FRACTION	Water Prequel		0 to 1	Clamped to range	Used for initializing the saturation of the unsaturated zone in the underground.
Bottom Resistance	BOTTOM_RESISTANCE	Water Prequel	days	0 to 1000000	Clamped to range	A grid of values containing the resistance of the lower layer against the bottom boundary flow.
Bottom Pressure	BOTTOM_PRESSURE	Water Prequel	m datum	-1000000 to 1000000	Clamped to range	A grid of values containing the head of the ground water pressure caused by ground water in higher regions outside the project area.
Max infiltration	MAX_INFILTRATION	Water Prequel	m	0 to 1000000	Clamped to range	Used in Infiltration only mode to limit the maximum amount of storage per gridcell.
Manning	MANNING	Water Prequel		0.01 to 0.255	Clamped to range	Used for overriding the surface terrain's manning value.

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Water Module

Water Module

Tutorials

Overview

Theory

Benchmarks

Group

Simulation data

Weather

Rain m • Evaporation m

Prequels

Bottom distance • Bottom pressure • Bottom resistance • Ground conductivity • Groundwater datum • Groundwater depth • Manning • Max infiltration • Microrelief • Surface level • Surface u • Surface v • Terrain elevation • Unsaturated fraction

Elevation

Elevation

Related

Building attributes • Hydrological features • Hydraulic structures •  Terrain attributes • Model attributes • Results