Terrain ground infiltration md (Water Overlay)

Icon	Attribute	Unit	Layer	Range	Description
	GROUND_INFILTRATION_MD	m/day	Surface		The speed at which water can flow vertically from the surface to the underground unsaturated zone.
	GROUND_INFILTRATION_MD	m/day	Underground		The speed at which water can flow vertically from the surface to the underground unsaturated zone.

Based on the properties of the terrain, water may infiltrate into the underground water system.

The speed at which water can infiltrate from the surface to the underground unsaturated zone is dependent on both the GROUND_INFILTRATION_MD of the surface terrain, as well as the GROUND_INFILTRATION_MD of any construction in that location, if present. Of the infiltration values of the construction and the surface terrain, the lowest value is used. If either has an infiltration value of 0, water cannot infiltrate into the underground unsaturated zone.

The maximum amount of water which can be stored in the saturated zone is based on the WATER_STORAGE_PERCENTAGE of the underground terrain.

Underground flow, or horizontal infiltration, are dependent on the infiltration properties of the underground, unless an aquifer exists at the same location.

Notes

The groundwater level reduction is inversely proportional to the WATER_STORAGE_PERCENTAGE, as the contribution of a given volume of water to the groundwater level increases when the capacity for water storage in the underground layer decreases.