2.0

Chapter 2 Working with Ponds
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6 Enter data into the Detention Basin Storage dialog box:
If you want to} Then}
define the rainfall distribution select type I, IA, II, or III from the Rainfall
Distribution list.
define the rainfall frequency select 1, 2, 5, 10, 25, 50, and 100 years from the
Rainfall Frequency list.
define the watershed drainage area type the area into the Drainage Area box or click
Select.
For more information, see Specifying the
Drainage Area in this chapter.
define the peak inflow type the peak inflow into the Peak Inflow box.
define the peak outflow type the peak outflow into the Peak Outflow box,
or click Select to display the Outflow Editor where
you can attach Inflow and Outflow structures to
your pond and determine peak outflows more
accurately.
For more information, see Specifying the Peak
Outflow in this chapter.
define the runoff flow type the runoff flow depth in the Runoff Flow
box.
NOTE
See the map in the SCS TR-55 document, page B-2, or contact your local
SCS office (now NRCS) to determine the appropriate rainfall distribution for
your project area and Runoff Flow values (this value is supplied
automatically if you use the Tabular or Graphical peak method).
NOTE
The Select button next to the Peak Outflow box is only available when a
pond definition is loaded. In addition, the View button at the bottom of
the dialog box is not active until you load a pond definition.
The Runoff Volume label displays the computed runoff volume. The Storage
Volume label displays the computed storage volume for the detention pond.
The Maximum Storage Elevation label displays the maximum storage elevation
of the currently selected pond.
7 Click Save to save the current detention basin storage data to a basin file (.bsn)
in the c:\Land Projects R2\<project name>\hd folder.
You can also do one of the following:
n
Click New to clear the data from the dialog box.
n
Click View to view the currently selected ponds stage-storage curve. The
View button is grayed out unless you select an .ssc file by clicking the SS
Curve button or load a pond definition by clicking the Pond button.
n
Click Output to display the default text editor with the basin design
information. From here, you can print the data to a printer or save it as a
text file.
8 Click OK to exit the Detention Basin Storage dialog box.