Hydrological attributes of terrains (Water Overlay)
Revision as of 16:39, 18 December 2020 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 construction is present with overwriting values.
Icon | Attribute | Unit | Layer | Range | Description |
---|---|---|---|---|---|
WATER | nominal | Surface | Whether this Terrain Type represents a form of water (and what type). | ||
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_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. | ||
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. | ||
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. | ||
GROUND_INFILTRATION_MD | m/day | Surface | The speed at which water can flow vertically from the surface to the unsaturated zone. | ||
GROUND_INFILTRATION_MD | m/day | Ground | The speed at which water can flow vertically from the surface to the unsaturated zone. | ||
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. |
Notes
- In general, surface terrain attributes can be overridden by attributes of constructions on the surface, even when the attribute values of the construction are set to 0.