Ground Infiltration Data Fields

Ground Infiltration data can be edited on either the Ground Infiltration Grid Window of the Subcatchments Grid or the Ground Infiltration Property Sheet.

All data can be edited on the grid or the property sheet.

This table describes all the data fields used to define a Ground Infiltration object.

Common Data Fields

Fields that are common to the majority of objects can be found in the Common Fields topic.

Ground Infiltration Data

Database Table Name: hw_ground_infiltration

Show Columns

Database Names

Size, Type and Units

Defaults and Error Limits

Field Name

Help Text

Database Field

Data Type

Size

Units

Precision

Default

Error Lower Limit

Error Upper Limit

Warning Lower Limit

Warning Upper Limit

Ground infiltration ID

A unique identifier for the ground infiltration record. This field is used to associate a Ground Infiltration ID with a particular subcatchment.

ground_id

Text

64

 

0

 

 

 

 

 

Soil depth

An estimate of the soil depth.

soil_depth

Double

 

Y

3

10.0

0

 

 

 

Percolation coefficient

A time coefficient, determined by calibration from existing data. It is recommended that the value should be between 0.1 and 10

percolation_coefficient

Double

 

TD

3

1.0

0

 

 

 

Baseflow coefficient

A time coefficient, determined by calibration from existing data. It is recommended that the value should be between 100 and 10000

baseflow_coefficient

Double

 

TD

3

1.0

0

 

 

 

Infiltration coefficient

A time coefficient, determined by calibration from existing data. It is recommended that the value should be between 0.1 and 10

infiltration_coefficient

Double

 

TD

3

1.0

0

 

 

 

Percolation threshold

The percentage saturation level of the soil at which water starts to percolate downwards

percolation_threshold

Double

 

 

3

50.0

0

 

 

 

Percolation percentage infiltrating

The percentage of percolation flow that infiltrates directly into the drainage network.

percolation_percentage

Double

 

 

3

5.0

0

100

 

 

Porosity of soil

A coefficient representing the porosity of the soil (upper storage reservoir)

soil_porosity

Double

 

 

3

50.0

0

100

 

 

Porosity of ground

A coefficient representing the porosity of the ground (lower storage reservoir)

ground_porosity

Double

 

 

3

50.0

0

 

 

 

Baseflow threshold level

The groundwater level at which secondary infiltration occurs.

baseflow_threshold

Double

 

Y

3

 

 

 

 

 

Baseflow threshold type

The Baseflow Threshold Level can be either an absolute value (relative to Model Datum) or a level relative to the chamber floor of the node to which the subcatchment drains.

Database Value

Description

Relative

Relative

Absolute

Absolute

baseflow_threshold_type

Text

8

 

0

Relative

 

 

 

 

Infiltration Threshold Level

The level of the groundwater storage reservoir at which groundwater infiltration occurs. It is recommended that the Infiltration Threshold Level should be between 0 and 5 m above the Baseflow Threshold.

infiltration_threshold

Double

 

Y

3

 

 

 

 

 

Infiltration threshold type

The Infiltration Threshold Level can be either an absolute value (relative to Model Datum) or a level relative to the chamber floor of the node to which the subcatchment drains.

Database Value

Description

Relative

Relative

Absolute

Absolute

infiltration_threshold_type

Text

8

 

0

Relative

 

 

 

 

Evapotranspiration type

The type of evapotranspiration can be set to either:

  • Linear - evapotranspiration varies linearly from the evaporation rate at ground level to zero at the specified Evapotranspiration depth.
  • Constant - the maximum value of evapotranspiration is applied above the specified Evapotranspiration depth. No evapotranspiration is applied below the Evapotranspiration depth.
evapotranspiration_type

Text

 

 

8

Linear

 

 

 

 

Evapotranspiration depth

The depth where evapotranspiration stops.

evapotranspiration_depth

Double

 

Y

3

 

0

 

 

 

Jan evapotranspiration factor The evapotranspiration factor applied to January. evapotranspiration_fac_Jan

Double

 

 

3

1.0

0

1

 

 

Feb evapotranspiration factor The evapotranspiration factor applied to February. evapotranspiration_fac_Feb

Double

 

 

3

1.0

0

1

 

 

Mar evapotranspiration factor The evapotranspiration factor applied to March. evapotranspiration_fac_Mar

Double

 

 

3

1.0

0

1

 

 

Apr evapotranspiration factor The evapotranspiration factor applied to April. evapotranspiration_fac_Apr

Double

 

 

3

1.0

0

1

 

 

May evapotranspiration factor The evapotranspiration factor applied to May. evapotranspiration_fac_May

Double

 

 

3

1.0

0

1

 

 

Jun evapotranspiration factor The evapotranspiration factor applied to June. evapotranspiration_fac_Jun

Double

 

 

3

1.0

0

1

 

 

Jul evapotranspiration factor The evapotranspiration factor applied to July. evapotranspiration_fac_Jul

Double

 

 

3

1.0

0

1

 

 

Aug evapotranspiration factor The evapotranspiration factor applied to August. evapotranspiration_fac_Aug

Double

 

 

3

1.0

0

1

 

 

Sep evapotranspiration factor The evapotranspiration factor applied to Septemeber. evapotranspiration_fac_Sep

Double

 

 

3

1.0

0

1

 

 

Oct evapotranspiration factor The evapotranspiration factor applied to October. evapotranspiration_fac_Oct

Double

 

 

3

1.0

0

1

 

 

Nov evapotranspiration factor The evapotranspiration factor applied to November. evapotranspiration_fac_Nov

Double

 

 

3

1.0

0

1

 

 

Dec evapotranspiration factor The evapotranspiration factor applied to December. evapotranspiration_fac_Dec

Double

 

 

3

1.0

0

1

 

 

Ground Infiltration

Subcatchments Grid

Calibration Guidelines