Hydrological attributes of terrains (Water Overlay)
Revision as of 10:10, 24 January 2024 by Frank@tygron.nl (talk | contribs)
Terrains in a project have a number of hydrological properties which can influence the flow of water in a project. Because there is always both surface and underground terrain defined for the entirety of the project area, all cells are affected by all properties of terrains, unless a building is present with overwriting values.
Icon | Attribute | Unit | Layer | Range | Description |
---|---|---|---|---|---|
HYDRAULIC_CONDUCTIVITY_MD | m/day | Ground | The hydraulic conductivity (symbolically represented as K) is defined as the speed by which water moves through the saturated zone horizontally. | ||
HYDRAULIC_CONDUCTIVITY_WITH_THICKNESS_MD | m2/day | Ground | The hydraulic conductivity (symbolically represented as KD) is defined as the speed by which water moves through the saturated layer horizontally, multiplied with the layer thickness. | ||
GROUND_INFILTRATION_MD | m/day | Surface | 0 to 10 | The speed at which water can flow vertically from the surface to the unsaturated zone. | |
GROUND_INFILTRATION_MD | m/day | Ground | 0 to 10 | The speed at which water can flow vertically from the surface to the unsaturated zone. | |
ROOT_DEPTH_M | m | Surface | The depth of the roots of the terrain type. This depth is used to determine whether evaporation will occur from the groundwater. | ||
WATER | nominal | Surface | Whether this Terrain Type represents a form of water (and what type). | ||
WATER_EVAPORATION_FACTOR | factor | Surface | How fast this terrain can evaporate water from the ground. The weather's evaporation speed is multiplied by this factor to determine the rate of evaporation. | ||
WATER_MANNING | s/(m1/3) | Surface | The Gauckler–Manning coefficient of the terrain, which is a measure of surface roughness. Used in the surface flow computation of the Water Overlay. | ||
WATER_MICRORELIEF_M | m | Surface | 0 - 0.255 | The defined Microrelief in meters, which captures surface water. When captured, surface flow is halted until the defined threshold is reached. Evaporation and infiltration for water captured in Mircrorelief is still allowed. | |
WATER_STORAGE_PERCENTAGE | fraction (m3/m3) | Ground | The percentage (as a fraction) of the ground layer volume which can be filled with water. A lower percentage means the ground layer will be able to store less water, and the saturated zone will rise higher with the same amount of water in the ground layer. |
Notes
- In general, surface terrain attributes can be overridden by attributes of buildings on the surface, even when the attribute values of the building are set to 0.