The route for the freeway was determined through a multidisciplinary process to identify a range of reasonable alternatives that were studied in detail in the Environmental Impact Statement. The study process involved identifying, comparatively screening, and eliminating alternatives based on:
- input from the public
- a comparison of alignment alternatives
- surrounding communities, resources, and other factors
- the historical context of the freeway
- projected regional traffic conditions with and without a freeway
The final decision on the route for the freeway was determined by ADOT, the FHWA and MAG, the transportation authority and planning agency for the region. As a corridor that is part of a comprehensive regional plan developed by MAG, ADOT serves as the agency responsible for implementation of the plan, with FHWA providing the federal oversight required to access federal funds. FHWA is the lead federal agency responsible for implementing the requirements of the National Environmental Policy Act, the governing federal law, and was responsible for the ultimate decision in selecting a route for the freeway.