Technical data

Chapter 3 Performing Hydrologic Studies
40
To design a culvert (continued)
Steps
Use
to look up
8 Specify the flow rate for the culvert.
You can type a value directly, or you can calculate
a flow rate value by clicking Select to display the
Runoff Editor dialog box. From here, you can
display the Runoff Method Selection dialog box
to select an appropriate runoff method where you
can then either import or calculate the flow.
Specify the Flowrate
for a Culvert
9 Specify the Manning’s n roughness coefficient
value for the culvert.
You can type a value for Manning’s n, or you can
click Select and pick a Manning’s n value from a
list of standard values based on different types of
culvert materials.
Specify a Manning’s n
Roughness Coefficient
10 Specify the roadway elevation, the culvert inlet
elevation, and the culvert outlet elevation.
11 Click the Settings button to display the Culvert
Settings dialog box to specify inlet, outlet, or
optimum control conditions, entrance losses, flow
rate ranges, and number of culvert barrels.
Change the Culvert
Settings