There are three alignment alternatives resulting in a minimum cross-section along the cross road regardless of whether the facility is an over-or under pass. There are two types of alignments: Symmetrical Alignment and the Shifted Alignment. shows an example of symmetrical and shifted alignments. This results in distances of 600-ft to 750-ft between crossovers. If the distance between crossovers can be reduced, it can boost traffic operations and limit the amount of ROW needed.

Eliminating a few reverse curves can reduce the spacing between crossovers. shows alignment alternatives where the number of reverse curves has been reduced with a resultant increase in median width. This results in distances of 400-ft to 500-ft between crossovers. Chapter 7 of provides additional information on horizontal alignment options.