At a virtual community meeting last week to update residents about the CTA's Red and Purple Modernization Program, attendees got a sneak peek at the unique piece of construction equipment that will be used to assemble the new elevated structure that will replace a Red/Purple ‘L’ Line embankment between Leland (4700 N.) and Ardmore (5800 N.) avenues.
The new elevated structure will feature concrete components, shaped vaguely like upside-down hats, held together by suspension cables, similar to the Belmont Flyover elevated bypass structure the CTA is building for outbound Brown Line trains north of Lakeview's Belmont station. The new structure in Uptown and Edgewater will feature short barriers to reduce ‘L’ train noise, with separate structures for the northbound and southbound tracks. The four tracks will be spaced farther away from each other to allow for building wider platforms, elevators, and escalators. However, the shape of the structure will mean that the alley currently running east of the tracks will remain the same size.
An attendee asked how the CTA will be putting the structure together, and the impact the construction will have on the nearby buildings. The transit agency reps replied they will be using a custom-built overhead crane known as a gantry to assemble the track structure quicker than older construction methods would allow. The residents in attendance voiced concerns about noise levels during and after construction, and street closures.
The New Track Structures
Back when transit service launched along the corridor that eventually became the Red Line, the tracks north of the Wilson Avenue station were located at ground level. It took over a decade to accomplish, but in 1921, train service was relocated to an elevated structure that has survived, with only a few changes, for 100 years.
This spring, as part of the RPM Program, the CTA closed the Lawrence and Berwyn stations and began demolishing the part of the embankment where the northbound tracks were located. Now the agency is gearing up to replace the northbound tracks.
According the presentation, the CTA is currently starting the first stage of the process, putting in the support beams. Next, it will use the gantry to lift the prefabricated concrete pieces up and assemble them. The project staff described the resulting elevated structure as a bridge, since the pieces will be connected by cables, not unlike those used in suspension bridges. The presenters showed a video of a similar elevated structure being assembled in Montreal to give residents an idea of what that would look like. Once the elevated structure is in place, the CTA will put in the rails and the ties.
According to Kevin Buch, the project manager for contractor Walsh Construction, the gantry will allow the CTA to finish the structure much faster than would otherwise be possible, and it will allow the construction to be completed without disturbing neighboring buildings. The barriers along the edges of the structure will direct noise upward, reducing train noise levels. The fact that the project is using continuously welded rails will further reduce the noise.
That isn’t to say that there won’t be any impacts at all. Buch said that they will still need to close Ardmore, Hollywood, Bryn Mawr, Balmoral, Berwyn, Foster, and Lawrence avenues, as well Winona, Argyle, and Ainslie streets for extended periods of time, with Ardmore, Balmoral and Ainslie used as staging locations. The nearby alleys will need to be closed as well. “These impacts are minimal, but there will be impact to garages and parking,” he said.
Walsh-Fluor crews will start using the gantry at Ardmore and continue south until they reach Leland. The CTA expects to have the new northbound tracks up and running by the winter of 2022-23. The same process will begin on the southbound half later in 2023, with the goal of finishing it in 2024.
New Stations
As part of the project, the Lawrence, Argyle, Berwyn, and Bryn Mawr stations will be rebuilt from scratch. All four stations (at least in their elevated forms) originally had a main entrance and an auxiliary exit on opposite sides of the street, but Bryn Mawr was the only station that retained that layout. Bryn Mawr and Lawrence will each have their main entrance moved from the south side of the street to the north, which will allow for a better connection to westbound buses, but complicate transfers for riders who would be transferring from eastbound buses to the 'L'. Lawrence will get an axillary exist on the south side, while Bryn Mawr will get a secondary entrance at Hollywood Avenue, near what is now the north end of the platform.
Another thing that may be coming back is the more distinctive design for the Argyle stop. In 1991, in response to lobbying from the residents of the surrounding Little Vietnam community, the CTA not only spruced up the station, but also added Asian-influenced design elements, such as a pagoda on the roof, a teahouse style customer service agent booth and the red and green color scheme. Renovations in 2012 stripped away everything except the roof.
LaTrice Phillips-Brown, CTA’s community liason for the project, said that, when it came to the design of the new Argyle station, CTA “worked closely with stakeholders [so] that the station reflected the character and richness of the community.” The resulting design eliminated the pagoda roof, as well an the "Asia on Argyle" sign added above the viaduct in 2013, which was controversial at the time, for a less obviously Asian-inspired look.
Resident Feedback
For the most part, the residents' concerns centered around noise, the timing of the street closures and the support local businesses are getting. Tammy Chase, the director of communication for the RPM project, said that given the sheer scale of the project, it was impossible to spotlight every single business along the ‘L’ tracks. But she noted that in late 2020 the CTA launched the RPM Open for Business program, where businesses and nonprofits can submit their information so that CTA can spotlight them in its marketing efforts.
In addition the CTA is also working with local chambers of commerce and aldermen James Cappleman (46th) and Harry Osterman (48th), whose wards include the areas around the corridor south of Foster Avenue and north of Foster, respectively. “Also, we've been rolling out the series of videos that feature individual businesses within the project area, allowing businesses to tell their stories and what makes them special,” Chase added.
CTA project manager Michal Williams said that residents will be warned of any boarding changes well in advance, and there will be wayfinding signs to help riders find future temporary entrances and platforms. When asked whether the CTA will keep the space under the new elevated structures open for uses like parking, Williams said the agency will fence these areas off for security and to help with future maintenance.
Asked about bridge clearance, Rob Cheeseman, senior project manager with Wash, said that it will be increased from the current 11 feet to 14.6 feet so “ we won't have trucks [getting] stuck under the bridges anymore.” When asked how CTA will address asphalt damage from the use of heavy construction equipment, Cheeseman said that will be part of the second phase of construction.
Chase said the CTA hasn’t decided when the sections of the Red Line further north will get rehabbed. "Future phases of RPM are still being determined, so which stations will be included in next phase is still to be determined, and will be announced to the community when we have the decision on that,” she said.