I-86, I-15 Wye OPass System Interchange

Stanley Consultants provided a value planning study for Idaho Transporation Department (ITD) to support programming and pre-design activities for this system-to-system interchange project. During the study it became apparent that the overwhelming project driver was to enhance safety. The idea was proposed to reduce the directional ramp speed by 5 mph. This allowed for improvements to stay within the existing right of way, allowed new alignment to match existing curve geometrics and simplified phased construction. ITD was able to save $20- to $25 million from an otherwise $81 million project by reducing the ramp speed.