Note for sag curves, when the algebraic difference of grades is 1.75 percent or less,
stopping sight distance is not restricted by the curve. In these cases, the equations in
Table 2.19 will not provide meaningful answers. Minimum lengths of sag vertical
curves are necessary to provide a pleasing general appearance of the highway. To
accomplish this, the minimum length of a sag curve in feet should be equal to 3 times
the design speed in miles per hour