Agriculture Reference
In-Depth Information
Figures 11.4 and 11.5 illustrate what contours might look like if they
were drawn on actual landscapes. Figure 11.4 represents a more or less
uniform slope of 10 to 15 percent. The contours are spaced (horizontal
distance) approximately 7 to 10 feet apart. Figure 11.5 is a hillside slope
with a constructed pond at the foot of the sloping ground. In both cases
the contours are conceptual, drawn as diagrams and not intended as
accurate representations.
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Figure 11.4
Visualizing a slope with contour lines
Figure 11.5
Contour lines reveal a sculpted landform
contourS uSed to ShoW Landform
There are two major reasons for site grading. The first—and we will dis-
cuss this and the other reason more fully in the following sections—is
to modify the existing landforms of a site to accommodate the pro-
grammed elements, creating level areas for building pads, for instance,
or gently sloping ground to accommodate a road or walking trail. The
second is to reshape the existing landforms to direct water away from
areas where it is not wanted. For example, the designer may direct sur-
face water away from the front of a building, to prevent flooding, or use
grading to avoid ponding (standing water) in a programmed use area on
the site. To accomplish either goal, the designer prepares a site-grading
plan. The creation of this plan involves a combination of contour
