2.0

Chapter 2 Working with Ponds
154
Creating a Pond Rating or a Stage-Discharge
Curve for the Current Pond
While you are designing the inflow and outflow structures for a pond, you can
review the resultant stage-discharge and rating curves and you can save them to
files that you can use when calculating the pond routing.
To create a pond rating or a stage-discharge curve for the current pond
1 From the Hydrology menu, choose Outflow Editor ä By Pond to display the
Pond Name dialog box.
2 Select the name of the pond, and then click OK to display the Pond Outflow
Design dialog box.
3 Click Plot at the bottom of the dialog box to display the Outflow Curve dialog
box.
The stage-discharge and rating curves plot the depth (or stage) against the
flowrate. You can use the Begin Elev and End Elev boxes to define the elevation
range for which you want to view the flowrate.
4 In the Begin Elev box, type the elevation at which to begin the elevation range.
5 In the End Elev box, type the elevation at which to end the elevation range.
6 In the Increment box, type the elevation increment for the graph of the rating
table curve or stage discharge curve.
7 To retain the outflow curve setup settings made in the Outflow Curve dialog
box, select the Keep Settings check box.
8 To display a curve, do one of the following:
n
Click Rating Table to display the composite rating curve.
n
Click Stage-Discharge to display the stage-discharge curve.
9 From the Rating Curve Display dialog box or the Stage-Discharge Curve dialog
box, change the graph settings, plot the data, save or output the curve:
If you want to} Then click}
change the hydrographs settings Settings.
plot the data on a graph and insert
the graph in your drawing
Plot.
output the data to an ASCII or .wk1
file
Output.
save the graph Save.
10 To save the rating curve, click Save Rating Curve to display the Save Rating
Curve File dialog box. Save the file to c:\Land Projects R2\<project name>\hd
folder. The rating curve file is saved with an .rtc file extension.
11 To save the stage-discharge curve, click Save Stage-Discharge.
The Save Stage-Discharge File dialog box is displayed. Save the file to c:\Land
Projects R2\<project name>\hd folder. The stage-discharge file is saved with an
.sdc file extension.