Ballast restrains the movement of crossties to prevent lateral movement of the track structure, provides distributive support to the crossties, and provides drainage for the track structure above. Desired

typical

ballast depth is within 2 inches of top of the ties and 9 to 12 inches below the bottom of the ties. The width of the ballast section is usually 6 to 12 inches from the ends of the tie with a two-to-one slope downward from that point to ground level.