Red and Purple Modernization Project
| Company type | Infrastructure project |
|---|---|
| Industry | Public transportation |
| Founder | Chicago Transit Authority |
| Headquarters | Chicago , United States |
Area served | Chicago's North Side, Evanston, Wilmette |
Key people | Chicago Transit Authority |
| Products | Rail infrastructure modernization |
| Owner | Chicago Transit Authority |
The Red and Purple Modernization (RPM) Project represents a comprehensive, multi-stage overhaul managed by the Chicago Transit Authority (CTA) that spans Chicago's North Side, as well as the suburbs of Evanston and Wilmette. As a component of the larger Red Ahead initiative, RPM focuses on upgrading outdated infrastructure along two branches of the Chicago "L": the North Side main line north of Belmont station, which serves both the Red and Purple lines, and the Evanston branch of the Purple Line. The first phase, completed on July 20, 2025, involved building a flying junction at Clark Junction to link the North Side main line with the Ravenswood branch, alongside reconstructing the stretch between and stations.
Early history
The North Side main line was inaugurated on May 31, 1900, by the Northwestern Elevated Railroad, running from the Loop Elevated to Wilson station. The Ravenswood branch followed in 1907, extending from Clark Junction just north of Belmont station to Kimball station. By 1908, the main line had been extended along former Chicago and Evanston Railroad (C&E) tracks reaching Central station in Evanston, ultimately arriving at Linden station in Wilmette by 1912.
Between 1908 and 1931, gradual elevation of the North Side main line and Evanston branch took place from Wilson to stations. An embankment was built to accommodate heavy C&E freight trains that ran parallel to rapid transit until April 30, 1973; these embankment tracks continue in use for transit operations today.
Prior improvements
In 2012, an $86-million project named Red North Station Interim Improvements rehabilitated the segment of the North Side main line between Wilson and , with Kiewit Infrastructure awarded $57.4 million to execute this work. Multiple stations—excluding , , and —underwent phased closures for renovation from June through December 2012. By June 2013, newly installed public artworks adorned all upgraded stations.
Separately, Loyola station underwent a $17-million transformation between 2012 and 2013 that included a new public plaza; this contract was also awarded to Kiewit Infrastructure.
Prior to the mid-2010s, Wilson station’s southbound express track featured a brief deviation due to its original design accommodating C&E freight traffic. From 2014 through 2017, Wilson was entirely rebuilt in a $203-million effort that introduced Purple Line Express service along with modernized platforms, entrances, and artistic installations.
Pre-construction
Between 2009 and 2010, the CTA undertook the North Red and Purple Line Vision Study focusing on the North Side main line and Evanston branch from Belmont to . The study identified issues such as aging track infrastructure, obsolete signaling systems, subpar stations causing slow zones, limited ADA accessibility, and insufficient capacity to handle increasing ridership. In October 2010, modernization emerged as the preferred solution.
Starting in January 2011, the CTA collaborated with the Federal Transit Administration (FTA) to prepare an environmental impact statement (EIS) for what became known as the "Red and Purple Modernization Project," accompanied by public engagement sessions. Various initial proposals—including a reduced-track elevated viaduct and a double-track subway option—were ultimately dismissed.
In November 2013, CTA applied for an FTA Core Capacity grant and received $35 million in August 2014; additional funding depended on subsequent federal approvals.
In early 2014, RPM was segmented into phases. A new EIS concentrated specifically on Phase One—comprising the Red-Purple Bypass at Clark Junction and the Lawrence–Bryn Mawr section—which was completed in 2015 with categorical exclusions and findings indicating no significant environmental impact.
On November 30, 2016, the Chicago City Council created a tax increment financing (TIF) district lasting 36 years along much of the North Side main line corridor to assist in funding modernization efforts. This financial mechanism enabled CTA to secure $1.1 billion in federal grants finalized in January 2017 through a Full-Funding Grant Agreement with FTA. Federal contributions included $956.61 million from Core Capacity grants and $115.73 million from Congestion Mitigation grants; local sources comprised $610.06 million from TIF revenues plus $384.30 million derived from CTA sales tax revenues. The total estimated cost for Phase One was established at $2.1 billion.
In June 2017, CTA issued a Request for Qualifications seeking contractors for the project. By December 13, 2018, the Walsh-Fluor Design Build Team—a partnership between Walsh Group and Fluor Corporation—was awarded a $1.2-billion contract to serve as general contractor for Phase One of RPM.
Criticism
The CTA once explored the idea of merging stations that were situated very close to each other to shorten travel durations, but abandoned this approach after local residents and aldermen perceived it as a reduction in service.
Opposition arose from residents near Clark Junction against the Brown Line flyover project due to the planned demolition of 16 homes and concerns about its visual effects. At the time, mayoral candidate Chuy García condemned the initiative as "an unnecessary use of taxpayer money with minimal return."
Phase One
The initial phase of construction kicked off on October 2, 2019, concentrating on Clark Junction along with the stretch between Lawrence and Bryn Mawr stations.
Lawrence to Bryn Mawr
Before Stage A began in 2021, the CTA installed interlockings close to Montrose and Thorndale avenues, facilitating train transitions onto temporary tracks during construction. Temporary station setups were created at Argyle and Bryn Mawr, while Lawrence and Berwyn stations remained closed for two construction phases. Due to limited space, the new viaduct was assembled using precast segmental box girders mounted with a launching gantry.
Stage A
Starting May 16, 2021, Stage A involved closing Lawrence and Berwyn stations and opening temporary facilities at Argyle and Bryn Mawr. Train operations shifted onto the two westernmost tracks to permit replacement work on the eastern tracks. This stage emphasized track improvements and station renovations essential for advancing the Red-Purple Modernization Program.
Stage B
Following the completion of Stage A on July 28, 2023, Stage B commenced. Train service moved onto two newly reconstructed tracks while work began on the westernmost pair. Argyle station was relocated to Foster Avenue and Winona Street; access at Bryn Mawr was limited to trains heading toward 95th-bound Red Line destinations. Construction started on permanent station facilities at Lawrence, Argyle, Berwyn, and Bryn Mawr.
These permanent stations officially opened on July 20, 2025.
Public space
The removal of embankment tracks freed up ten blocks of public land beneath the railway. Throughout 2024 construction activities, the CTA held community meetings to gather input on potential features. The finalized design, completed by February 2025, includes a pedestrian walkway, parking areas, and recreational amenities. Construction is planned for 2026 through 2027.
Red-Purple Bypass
The Red-Purple Bypass incorporates a Brown Line flyover ramp alongside a straighter main line alignment situated north of Belmont. The flyover structure was constructed using steel plate girders, whereas the new main line viaduct primarily utilizes precast prestressed concrete girders. Except for the straddle bent above the main line, decorative grooves adorn the concrete piers.
Construction started in 2019 with installation of the flyover ramp, which opened for Brown Line service on November 19, 2021. In March 2022, reports surfaced about concrete spalling on flyover walls attributed to frost weathering. Despite this deterioration, structural safety remained uncompromised. Repairs were finalized by December 2022.
In August 2021, the historic Vautravers Building was shifted westward to facilitate straightening of the main line north of Belmont. Work on this new alignment began late in 2021. The two westernmost tracks reopened in December 2023; reconstruction of the easternmost tracks is ongoing through 2025.
Future phases
The CTA is currently assessing upcoming stages that include the Evanston branch along with the remaining portions of the North Side main line stretching from Addison to Sheridan and from Thorndale to Howard. The RPM Next Phases Study, conducted between 2021 and 2024, involved multiple public forums held in March 2023, November 2023, and February 2024 to review and gather input on the proposed plans.
The schedule for these future developments remains indefinite due to limitations in available funding.
See also
- Brown Line Capacity Expansion Project – extensive Brown Line reconstruction during the 2000s
- Red Line Extension – significant Red Line initiative as part of the Red Ahead program