Rain gages supply rainfall data for one or more subbasins in the study area. The rainfall data can either be user-defined or described in an external file. Rain gages are part of the project and can be shared by multiple basins or meteorologic models.
The user can define the rain gage time series data using the Rain Gage Data command. The defined rain gage time series data can later be used for each subbasin in the stormwater analysis.
Follow the steps below to use the Rain Gage Data command:
- From the Input ribbon menu, select the Rain Gage Data command.
- The Rain Gage Data dialog box will be displayed, as shown below.
The following sections describe how to use the Rain Gage Data command and interact with the above dialog box.
Selecting Rain Gages
The Select Rain Gage section allows the user to select the rain gage for which rain gage data will be defined. In this section, the user can create, delete, or copy existing rain gage data to a new rain gage. In addition, the user can navigate between rain gages and enter a description for each rain gage.
The following entries are provided in this section:
- Rain gage ID
This dropdown combo box lists all the rain gages that are defined in the current scenario. Click on the edit option (i.e., pencil icon) to edit the rain gage ID. The user can navigate between the previous and next rain gage using the Up and Down arrow buttons. Note that the Up and Down arrow buttons will be disabled (i.e., grayed out) if the current scenario contains a single rain gage.
- Description
This optional text field allows the user to enter additional information that describes the selected rain gage.
- New
The [New] button allows the user to create a new rain gage on the Map View. The ID of every newly created rain gage must be unique.
- Copy
The [Copy] button allows the user to copy an existing rain gage along with its associated data to a new rain gage. The software automatically provides a unique ID to the copied rain gage.
- Delete
The [Delete] button allows the user to delete the selected rain gage from the current scenario.
Rain Gage Specifications
Rain Gage Location
This section allows the user to provide a precise description of the rain gage’s location. The location is specified for each gage in latitude and longitude. The latitude and longitude can be entered in decimal degrees in the Latitude and Longitude fields, respectively. Upon entering the latitude and longitude, the software will provide the location’s physical address in the Location read-only field. Alternatively, the user can click the [Pick] button to interactively select the location from the Map View. The software will then display the physical address, longitude, and latitude values for the selected location in the respective fields. The user can click the [Clear] button to cancel the previous selection and redo the entire process.
DSS Data
This section allows the user to select a DSS data file to define the rain gage time series data. Select the radio button on the DSS Data section to enable the content of this section. Otherwise, this section is disabled (i.e., grayed out).
Note that the DSS Data section is not available when EPA SWMM is selected as the hydrology analysis engine in the Scenario Manager dialog box. Refer to this article in our knowledge base to learn more about the hydrology analysis engines.
The following parameters are provided in this section:
- DSS file
This entry denotes the file directory path to the DSS data file. Clicking on the [Select] button allows the user to select the directory path and data path using the DSS Data File & Path dialog box. Refer to this article in our knowledge base to learn more about the DSS Data File & Path dialog box.
- DSS path
This entry denotes the data path within the DSS data file, which contains the rain gage data.
External Data File
This section allows the user to select an external data file to define the rain gage data. The Data file entry denotes the directory path and name of the external data file. Click the [Select] button to select the directory path and name of the external data file. Select the radio button on the External Data File section to enable the contents of this section. Otherwise, this section is disabled (i.e., grayed out).
Note that the External Data File section is only available when EPA SWMM is selected as the hydrology analysis engine in the Scenario Manager dialog box. Refer to this article in our knowledge base to learn more about the hydrology analysis engine.
Time Series Data
This section allows the user to manually enter time series data for the selected element. Select the radio button on the Time-Series Data section to enable the contents of this section. Otherwise, this section is disabled (i.e., grayed out).
The following parameters are provided in this section:
- Rainfall type
This dropdown combo box is used to define the type of data that is to be entered. The following options are available:
- Cumulative (default)
- Incremental
- Intensity
Note that the Rainfall type dropdown combo box is only available when EPA SWMM is selected as the hydrology analysis engine in the Scenario Manager dialog box. Refer to this article in our knowledge base to learn more about the hydrology analysis engines.
- Time increment
This dropdown combo box is used to select the time increment that defines the time series data. The following table shows the options available in this dropdown combo box:
Minutes Hours Days 1 minute 1 hour 1 day 2 minutes 2 hours 3 minutes 3 hours 4 minutes 4 hours 5 minutes 6 hours 6 minutes 8 hours 10 minutes 12 hours 15 minutes 20 minutes 30 minutes
- Time window
This dropdown combo box is used to select the type of time window data that is to be entered. The following options are available.
- From Control Data
- User-Defined (default)
- Select control
This dropdown combo box is used to define the control data set to use. This dropdown combo box is only enabled when From Control Data is selected as a time window. Otherwise, this dropdown combo box is disabled. If only one control data set is defined, then the software will automatically select that control data set. When a control data set is selected, the software will automatically populate the following fields:
- Start date & Start time
- End date & End time
- Start date/Start time/End date/End time
These fields define the time period for the element data. When From Control Data is selected as a time window, these fields become read-only fields, and the software will automatically fill-in the starting and ending dates and times. When User-Defined is selected as a time window, these fields allow manual entry of dates and times.
- Time Series Table
The Time column values automatically fill-in, based upon the selected Time Increment and Start/End dates & times. The user can manually enter data values into the Precipitation column fields.
Rainfall Time Series Plot
The section displays the Precipitation (in) vs Time plot of the selected rain gage data. If no time series data are available for the specified time window, the graph will not show any data.