(in 2003) for IL 390 are 39,600 vehicles for the western and around 82,000 to 87,000 cars per day for the remainder. On October 29, 2013, IDOT announced that the highway was re-designated IL 390 at groundbreaking ceremonies for the Elgin–O’Hare Western Access Project. Shortly after, maintenance of the road was transferred to the Illinois State Toll Highway Authority (ISTHA), and toll collection on the existing segment from US 20 in Hanover Park to I-290 in Itasca began in 2016. ISTHA began constructing an eastward extension of IL 390 to a new interchange on the western border of O'Hare International Airport with the planned I-490 connecting I-90 to the north and I-294 to the south. This interchange may also incorporate ramps into a planned western terminal at O'Hare. The official groundbreaking for the expansion took place on October 29, 2013. The first segment of this extension, opened at a ribbon-cutting ceremony on November 1, 2017, stretching from the upgraded interchange with I-290 in Itasca to IL 83 in Bensenville. East of I-290, IL 390 was formerly a four-lane arterial at-grade road known as Thorndale Avenue until its upgrade into an extension of IL 390, along with the interchange with I-290. Thorndale Avenue ran from I-290 to York Road near the western border of O'Hare International Airport. After its upgrade, the Thorndale Avenue designation was assigned to the new frontage roads along both sides of the eastern extension of IL 390. Future The remaining section of IL 390 from IL 83 in Bensenville to the western edge of O'Hare International Airport is currently under construction and is expected to open by 2024. , a feasibility study is underway on the western extension of IL 390 from US 20 to North Avenue in Bartlett, as well as improvements to US 20 between North Avenue in Bartlett and Shales Parkway in Elgin. However, unlike the original plans, the entire extension is proposed to be an arterial road rather than a limited–access freeway or tollway. Exit list The remaining portion of Thorndale Avenue will continue as a frontage road of IL-390. References External links Illinois Highway Ends: Elgin-O'Hare Expressway Airport Planning & O'Hare Airport (DuPage County) O'Hare International Airport Master Plan 390 Expressways in the Chicago area O'Hare International Airport Toll roads in Illinois Interstate 90 Transportation in DuPage County, Illinois Transportation in Cook County, Illinois