What do topographic lines indicate on a survey map?

Topographic lines on a survey map are essential for conveying the three-dimensional shape of the terrain in a two-dimensional format. These lines, which are often referred to as contour lines, connect points of equal elevation on the landscape. By analyzing the spacing and configuration of these lines, one can determine the slope of the land.

When contour lines are close together, they indicate a steep slope, while lines that are spaced further apart represent a gentler slope. If the lines form loops, they can illustrate hilltops, valleys, or depressions. Thus, understanding topographic lines enables surveyors to communicate crucial information about elevation changes, gradients, and the overall shape of the land surface, which is vital for various planning and construction purposes.

While boundaries of legal properties, areas of vegetation, and locations of underground utilities are important in surveying, they are represented differently on a map and do not fall under the functions of topographic lines. Therefore, the focus on slope and contour of the land makes the selected answer the appropriate choice.