Surface infiltration formula (Water Overlay)

Surface infiltration is the amount of water that infiltrates from the surface to the unsaturated zone below the surface.

Surface infiltration is calculated per grid cell. First, the infiltration capacities are calculated:

${\bar {I}}_{top}={\begin{cases}{\bar {I}}_{con},&{\text{if constructions are present on top of the surface}}\\{\bar {I}}_{terrain},&{\text{otherwise}}\\\end{cases}}$

${\bar {I}}_{surface}=min({\bar {I}}_{ground},{\bar {I}}_{top})$

Then the actual infiltration:

$\Delta w_{t}=min(h_{t},{\bar {I}}_{surface}\cdot \Delta t\cdot f_{i,t})$

Where:

${\bar {I}}_{con}$ = The average infiltration capacity based on constructions on top of the surface, based on GROUND_INFILTRATION_MD defined in either the building or function.

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \bar{I}_{terrain}} = The average infiltration capacity based on the surface terrain, defined by GROUND_INFILTRATION_MD. This value should be interpreted as the vertical conductivity (Kv) of the sub-soil.

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \bar{I}_{top}} = The average infiltration capacity on top of the surface.

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \bar{I}_{ground}} = The average infiltration capacity below the surface.

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \bar{I}_{surface}} = The infiltration capacity from surface to the unsaturated zone.

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \Delta w_t} = The surface infiltration which takes place at time Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle t} .

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle h_t} = The amount of water on the surface at time Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle t} . Also known as the water column.

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \Delta t} = Computational timestep.

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle f_{i,t}} = The interpolated infiltration factor at time Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle t} . Configured using INFILTRATION_FACTOR_S.

Related

The following topics are related to this formula.

Formulas

Surface water level formula

Groundwater level formula

Underground infiltration formula

Models

Surface model

Underground model

Infiltration model

Tracer flow model

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Surface • Ground • Rain • Evaporation • Infiltration • Elevation • Breach • Sewer • Storage • Tracer flow • Border • Order

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Surface flow • Surface infiltration • Ground flow • Ground infiltration • Surface evaporation • Ground evaporation • Ground bottom flow

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Related

Building attributes • Hydrological features • Hydraulic structures •  Terrain attributes • Model attributes • Results • Simulation data