Grade-separated intersections increase capacity by eliminating the delay caused by a previous intersection or railroad. Traffic moves freely, and signals may only be necessary for accessing the exit and entrance ramps of the interchange.

Elevating one portion of a street or rail crossing improves safety by eliminating vehicle, pedestrian, and train conflicts. The chance of collisions is decreased because:

Refer to the reports for the benefits of changing to a grade-separated interchange. Converting a four-way stop to a grade separated intersection reduces injury crashes by 57 percent. Converting a signalized intersection reduces injury crashes by 28 percent.