Terrain elevation prequel (Water Overlay)

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 to datum height values. Prequel Overlay must be set inactive.

This prequel serves as a replacement for the DTM, which is the elevation model without the Buildings. The Water Overlay will still add the heights of any Buildings present, in accordance with the set DESIGN_FLOOD_ELEVATION M.

Notes

• IMPORTANT: This prequel Overlay must be set to inactive in order to function properly!
• The values in this prequel grid are clamped between -10000.0 and 10000.0. No data values are not allowed.
• Any Grid Overlay used as input for this prequel should cover the project map completely, without any NO_DATA values. If the dataset used does contain NO_DATA values, it is prudent to use a Combo Overlay or an Average Overlay to fill up any NO_DATA values, and use that Grid Overlay as input for this prequel instead.

See also

• Elevation model (Water Overlay)
• Prequel
• Bridge elevation (Water Overlay)

API Endpoints

• Api session event editor overlay set prequel

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Water Module

Water Module

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

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Elevation model

Related

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