About Creating Standard Breaklines

Use the Add Breaklines dialog box to create standard breaklines.

You can use 3D lines, grading feature lines, splines, and 3D polylines as breaklines. The X, Y, and Z coordinates of each vertex on the polyline that you select are converted into TIN vertices. For 3D lines, each line that you select is defined as a two-point breakline.

Important: If you select a 2D polyline with a zero elevation, then it is saved with that elevation. Use proximity breaklines if you want the elevations calculated automatically.