The project includes track and station improvements on the 20.1km section of the line between Grand and Cumberland stations, eliminating a number of speed restrictions, as well as upgrading of signalling systems between Jefferson Park and O'Hare.
Traction power supplies will also be improved and wireless telecommunications in tunnels will be upgraded to provide faster and more reliable voice and data transmission. The existing wireless infrastructure was installed in 2005 but is already considered inadequate.
The four-year programme is being funded through local, state, and federal sources, and work is expected to begin next year, starting with track work before moving on to station renovations, power upgrades, and signalling improvements.
CTA says weekday ridership on the O'Hare Branch has increased by 25% in the last five years to more than 80,000 passengers per day. The Logan Square – Grand section of the line has seen a 44% increase in ridership over the last five years and almost 60% over the last 10 years, the fastest growth anywhere on the CTA rail network during this period.
According to CTA the project is largest investment in the line since the completion of the Jefferson Park – O'Hare extension in 1983.