Groundwater level formula (Water Overlay)

Groundwater level is calculated per cell.

h_{u}={\frac {\Delta w_{s}}{sp}}

gl_{u}=h_{u}+B-d_{b}

Where:

$h_{u}$ = The height (column) of the saturated zone.
$\Delta w_{s}$ = The amount of water in the saturated zone. The height of the water column if the equivalent amount of water was placed on the surface.
$sp$ = The WATER_STORAGE_PERCENTAGE of the underground terrain type, used here as a fraction.
$gl_{u}$ = The groundwater level, relative to datum. Also known as the watertable.

$B$ = The surface height in the cell, relative to datum.
$d_{b}$ = The GROUND_BOTTOM_DISTANCE_M (effectively available height in the underground model).