To Create Feature Lines From Objects

Click Home tabCreate Design panelFeature Line drop-downCreate Feature Lines From Objects Find.
In the drawing, select one or more polylines, lines, or arcs. Then press Enter.
Note: You can enter Xref to select an object from an Xref.

You can select the objects one at a time, or you can make a multiple selection by drawing a window.
In the Create Feature Lines dialog box, specify the feature line options. When creating a feature line you can manually enter an elevation or assign an elevation from a surface or from grading when creating a feature line from objects. For more information, see To Assign Feature Line Elevations when Creating Feature Lines from Objects.
To edit the feature line elevations, see Editing Feature Line Elevations.