Maricopa County took charge of what was then called the Estrella Freeway project when it was dropped from the regional freeway plans, maintaining it as an interim two-lane highway along the original corridor while keeping the state route designation. The county then made significant improvements to the roadway, extending it several miles north and east of US 60. While the highway was still largely a two-lane rural road, the extension north of US 60 along with the southern terminus just north of Interstate 10 was upgraded to a four-lane divided parkway, and the segment between US 60 and Bell Road in Surprise was partially upgraded to controlled-highway standards with overpasses and right-of-way for on-ramps.