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Table Of Contents
Chapter 5 Working with Hydrology Commands
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Curve Number field. For more information, see Selecting and Editing the
Runoff Curve Numbers for Different Soil Groups and Cover Types in this
chapter.
4 To select a value from the Composite Runoff Curve Number Calculator, see
Calculating a Composite or Weighted Curve Number for More Than One
Watershed or Subarea in this chapter.
Calculating the Peak Runoff Flow by Using the
TR-55 Tabular Method
The Tabular Method for runoff calculation is used to calculate peak discharge
runoff and generate hydrographs for single or multiple watershed subareas.
The TR-55 Tabular Method calculator simplifies the process of calculating peak
runoff by doing the calculations for you. You enter the required data (rainfall
distribution type, drainage area, time of concentration, time of travel,
downstream subareas, the 24-hour rainfall intensity, and the runoff curve
number), and the calculator determines the peak flow value and creates a
hydrograph.
To calculate the peak runoff flow by using the TR-55 tabular method
1 From the Hydrology menu, choose Runoff ä TR-55 Tabular Method to display
the TR-55 Tabular Hydrograph Method dialog box.
TIP
To load a runoff calculation that you previously saved, click Load.