Infiltration Surface (2D) data can be edited on either the Infiltration Surface (2D) Grid Window of the Polygons Grid or the Infiltration Surface (2D) Property Sheet.
Most data can be edited on the grid, but some fields cannot be displayed in the grid format.
To view and edit all zone data, use the Property Sheet.
The following describes all the data which can be used to define a Infiltration Surface (2D) .
Fields that are common to the majority of objects can be found in the Common Fields topic.
Infiltration Surface (2D) Data
Database Table Name: hw_2d_infil_surface
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Field Name |
Help Text |
Database Field |
Size |
Precision |
Default |
Error Lower Limit |
Error Upper Limit |
Warning Lower Limit |
Warning Upper Limit |
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|
ID |
The name of the surface |
surface_id |
Text |
64 |
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0 |
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| Infiltration type |
An infiltration model can be chosen from the dropdown.
|
runoff_volume_type | Text | 10 | 0 | ||||||||||||||||||||
| Fixed runoff coefficient |
This is a proportion. For example, 0.1 indicates 10% runoff from this surface. Used when Infiltration type is set to Fixed or ConstInf. |
runoff_coefficient | Double | 0 | 5 | 0 | 1 | ||||||||||||||||||
|
Horton initial |
Initial infiltration rate (f0) when soil water content is zero. Used when Infiltration type is set to Horton. |
initial_infiltration | Double | 0 | I | 3 | 0.001 | ||||||||||||||||||
| Horton limiting |
Limiting infiltration rate when soil is saturated and drainage capacity equals the infiltration rate. Used when Infiltration type is set to Horton. |
limiting_infiltration | Double | 0 | I | 3 | 0.001 | ||||||||||||||||||
| Horton decay |
Rate of decay of potential infiltration rate. Used when Infiltration type is set to Horton. |
decay_factor | Double | 0 | HR | 3 | 0.001 | ||||||||||||||||||
| Horton recovery |
Rate of recovery of potential infiltration rate. If this value is blank, the recovery factor is set to the same value as the Horton decay factor. Used when Infiltration type is set to Horton. |
recovery_factor | Double | 0 | HR | 3 | 0.001 | ||||||||||||||||||
| Infiltration loss coefficient |
Used to calculate the infiltration loss when Infiltration type is set to ConstInf. |
infiltration_coeff | Double | 0 | I | 1 | 0 | 0 | |||||||||||||||||
| Green-Ampt suction |
The average capillary suction at the wetting front. Used when Infiltration type is set to Green-Ampt. |
average_capillary_suction | Double | 0 | RD | 0 | |||||||||||||||||||
| Green-Ampt conductivity |
The minimum or asymptotic infiltration rate of the soil. This is equivalent to limiting infiltration rate in Horton. Used when Infiltration type is set to Green-Ampt. |
saturated_hydraulic_conductivity | Double | 0 | R | 0 | |||||||||||||||||||
| Green-Ampt deficit |
The maximum soil moisture deficit (the fractional difference between soil porosity and actual moisture content). Used when Infiltration type is set to Green-Ampt. |
initial_moisture_deficit | Double | 0 | 0.01 | 1 | |||||||||||||||||||
| Infiltration loss coefficient |
Infiltration rate when the soil layer is saturated. Used when Infiltration type is set to Deficit and Constant Loss. |
defconloss_infil_loss_coeff | Double | 0 | I | 3 | 0 | ||||||||||||||||||
| Maximum deficit |
Maximum amount of water that the soil layer can hold. Used when Infiltration type is set to Deficit and Constant Loss. |
defconloss_max_deficit | Double | 0 | ID | 3 | 0 | ||||||||||||||||||
| Curve number | The curve number used in the calculation of the maximum infiltration capacity.
Typical curve number values range from 0 to 100. In order to align with the SWMM implementation of curve number infiltration, if you specify a curve number that is more than 0 but less than 10, the simulation engine will automatically use a value of 10 in the calculation for CNSWMM infiltration. Similarly, if you specify a curve number that is greater than 99 but less than 100, the simulation engine will automatically use a value of 99 in the infiltration calculation. A comprehensive list of curve numbers is included in the Setting Runoff Coefficients from GIS Data topic. Used when Infiltration type is set to CNSWMM. |
curve_number | Double | 0 | 3 | 0 | 100 | ||||||||||||||||||
| Initial abstraction factor | The proportion of the storage depth that is retained on the surface before infiltration occurs.
An initial abstraction factor value of up to 0.2 is typically used. Used when Infiltration type is set to CNSWMM. |
initial_abstraction_factor | Double | 0 | 8 | 0.2 | 0 | 1 | |||||||||||||||||
| Drying time | Time in days for a fully saturated soil to dry completely. Typical values range from 2 to 14 days.
Used when Infiltration type is set to CNSWMM. |
drying_time | Double | 0 | 2 | 7 | 0.001 |