Now that the path averages have been calculated, the overall slope of the area or subareas must be calculated in
order that we can obtain the right coefficient from the "C" value chart. This can be accomplished by taking the
arithmetical average of all of the paths in the entire basin, if it is classified as simple, or the average of all of the
paths in each subarea if the basin is complex.
The overall slope of the area can be calculated using this formula:
Since this example is for a simple area, you will represent this entire basin with one "C" value for an overall slope
of 3.9 percent. If this example was a complex area, you would calculate the overall slope for each subarea and
use a "C" weighted formula.
STEP 9. Find the "C" value for the basin or subarea. Now you can go to table 2-1 on page 2-6 and find the
correct "C" value. GMd with turf slope 2 percent > < 7 percent 0.35. Refer to figure 2-8.
Figure 2-8. Basin
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