and accuracy. In time, you will become increasingly adept as you gain confidence through practice and by challenging yourself to discover more aesthetically exciting and innovative site-grading solutions.
Figure 9.1-A A pen mirrors slope of a steep embankment
Figure 9.1-B A landscape that was altered by a farmer with a variety of slopes, from steep to level
Slope in site grading refers to the angle or degree of the surface of a landform (such as the side face of a hill or the steepness of a river valley or drainage swale) or a paved surface (such as walkway or tennis court). The drawing pen in Figure 9.1-A is tilted so as to mirror the sloping surface of a constructed earth embankment. As you can see, the face of the embankment is quite steep; probably impossible to walk straight up on without considerable difficulty. The degree of steepness is expressed as a percent of slope, with slopes of 25 or 30 percent following in the steep range. Slopes of 2 or 5 percent are considered shallow or even almost level of surfaces that are 1 percent. In Figure 9.1-B the terrain is highly varied with steep to shallow sloping earth surfaces and everything in between. More on slope and angle of slopes will be discussed below.
Introducing Calculation of Slope Contour lines and spot elevations are the primary tools to modify the terrain of an existing project landscape. Used in combination, the manipulation of contours and establishment of spot elevations are the primary means to create level areas for buildings and sloping areas to direct water runoff, and to sculpt project terrain to accommodate safe circulation for 120
Landscape Site Grading Principles
