Infiltration Editing

The purpose of the Infiltration Editor is to assign soils to the Subcatchment for infiltration parameter determination. The percent of the pervious land area in the Subcatchment covered by each soil is entered next to its respective soil category. If the soil is not present in the Subcatchment its field can be left blank or the coverage value could be set to zero.

To initiate the Infiltration editor, do one of the following:

To edit Infiltration inputs for one Subcatchment at a time:

- Select Subcatchment, click on the icon located at the second row of the top of the attribute browser, and then select Infiltration from the initiated pop up menu. This will initiate the infiltration editor shown below.

Note: Once Infiltration properties are specified, the user needs to click on the button to save the properties or on the or button to cancel the changes and close the editor.

2. To edit Infiltration inputs for multiple Subcatchments at a time:

Select one of the group editing features (i.e., Group Editing on Selection () or Group Editing on Domain ()).
On the initiated Group Editing dialog, click on . These steps would activate the Infiltration Editor shown below.

Note:

Once infiltration properties are specified, the user needs to click on the button to save the properties, or on the or the buttons to cancel the changes, the button to close the editor.
The button deletes infiltration data for the selected Subcatchments only. The button empties infiltration data for all Subcatchments, not just the selected ones, in the drainage system.

The parameters listed in the editor are as follows:

Name	Description
Soil	Name of the soils defined in the project. The user cannot edit soil name from infiltration dialog box.
Description	Description of the soils defined in the project. The user cannot edit soil description from this dialog box.
Coverage (%)	Percentage of the pervious portion of the Subcatchment land area that is covered by the soil. For example, if the Subcatchment has only one soil type, value of coverage should be 100 for the soil, and 0 for all other soils that might have been defined in the project. The total coverage should not exceed 100, but could be less. If less, InfoSWMM scales up coverage of the soils available in the Subcatchment proportionally so that the coverages add up to 100.
Sort By	Sorts the soils defined in the project either by Soil ID, Soil Description, or Coverage. Select the sorting criteria from the dropdown combo box. By default InfoSWMM sorts soils in ascending order of their ID. To sort in descending order check the box.
Edit Soil	One may initiate the soil editor by clicking on the button, and create a new soil or edit properties of existing soils.

Note: The soil editor is used to define infiltration parameters of the major soils available in the drainage area, and the infiltration editor defines the percentage of the pervious portion of the Subcatchment that is covered by one or more of these soils. InfoSWMM derives infiltration parameter for every Subcatchment in the watershed based on the infiltration parameters defined in the soils editor, and the soil coverage defined in the infiltration editor. The model uses the weighted average of the infiltration parameters of the soils available in the Subcatchment.

Example: Assume the following conditions:

	Soil A	Soil B
Horton's Minimum Infiltration Rate (in/hour) - From Soil Editor	0.3	0.2
Pervious portion of Subcatchment X Covered by the soil (%) - From Infiltration Editor	60	40

Based on this information, minimum infiltration rate of Subcatchment X will be 0.6* 0.3 + 0.4 *0.2 = 0.26 in/hour.