Since the creation of Interstate 15, it has served as a long-haul route for North American commerce. It is now officially chartered for this purpose. From the junction of Interstate 515 in Las Vegas to the Canadian border, I-15 forms part of the CANAMEX Corridor, a High Priority Corridor, as a result of the North American Free Trade Agreement.[3]
Local portions were built to connect the Inland Empire with San Diego in California, facilitate tourism access to Las Vegas, interconnect all of the Metropolitan Statistical Areas in Utah except for Logan, and provide freeway bypasses for Pocatello, Idaho Falls, and Great Falls.
Since the construction of Interstate 15, California, Nevada, and Utah have consistently ranked in the fastest growing areas of the United States. As a result, the route of I-15 has substantially increased in population and commuter traffic has increased the traffic burden on the freeway. Current population estimates are that more than 75 percent of the population of Utah,[4] 19 percent of the population of California, and more than 70 percent of the population of Nevada live in counties where Interstate 15 is the primary Interstate Highway.