25: Displaced Left-Turn Interchange

Submitted by: Kansas City District

Innovation Description and Benefit:

The displaced left-turn interchange is an arrangement of vehicular movements that, as far as we are aware, is the first of its kind built in the world.  This geometry was selected after a thorough traffic modeling study which examined other diamond interchange variants including traditional, diverging (DDI), and single point.  The displaced left-turn geometry makes the traffic signals more efficient by altering phases and allowing different traffic movements to move concurrently.  By combining the best attributes of traditional diamonds (which excel with high through volumes but struggle with high left-turn volumes) and DDI (which excel with high left-turn volumes but struggle with high through volumes), the displaced left-turn geometry is a successful innovation.

For More Information Contact

Kansas City District

Ryan Hale at Ryan.Hale@Modot.mo.gov or (816) 607-2219.