The CTA Brown Line passes over a stretch of the Red-Purple Bypass where concrete debris was removed to prevent it from falling. Credit: Jake Wittich/Block Club Chicago

LAKEVIEW — Chunks of concrete are missing from the Chicago Transit Authority’s new Red-Purple Bypass that sails over Lakeview, alarming locals who took to social media to report the flaw and question the safety of the structure.

But the CTA said the missing sections of concrete — which leave steel rebar and PVC drainage pipes exposed — are only cosmetic and were knocked off safely by the contractor to remove a danger.

The concrete structure supporting the bypass started “spalling,” a condition in which concrete fragments break off their larger body, according to CTA spokesperson Tammy Chase. The transit authority discovered the spalling while conducting regular inspections of the structure.

“This is a quality issue related to the work performed by Walsh-Fluor, the contractor that built the bypass for CTA,” Chase said. “The likely cause of spalling is water getting into components of the bypass called PVC sleeves and then freezing, which put pressure on the surrounding material and caused the spalling.”

Crews have been removing debris from parts of the Brown Line flyover that have spalled, a cosmetic condition in which concrete fragments break off their larger body. Credit: Jake Wittich/Block Club Chicago

The CTA immediately asked Walsh-Fluor to perform daily inspections of the structure and remove any loose concrete immediately after discovering the spalling, Chase said. The areas of the structure that are missing concrete are a result of Walsh-Fluor workers cleaning out any loose debris before it has a chance to fall.

“The visible recessed areas are the result of proactive mitigations to protect the public and our employees from any falling debris, ahead of the contractor completing the repairs,” Chase said.

Walsh-Fluor will repair the spalls this spring at no cost to CTA, Chase said.

The spalling has been inspected by the CTA’s Safety Department, CTA engineers and Walsh-Fluor’s structural engineer, and it’s been determined the condition poses no safety nor does it adversely affect the bypass’s performance, Chase said.

The spalling was likely caused from water getting into the bypass’s PVC sleeves and then freezing, putting pressure on the surrounding concrete. Credit: Jake Wittich/Block Club Chicago

The Red-Purple Bypass is part of the CTA’s $2.1 billion Red and Purple Modernization project, which is in Phase 1. The flyover began service in November to allow Brown Line trains to more efficiently pass the Red and Purple line tracks in Lakeview.

The bypass eliminates a 114-year-old rail junction between the Red, Purple and Brown line trains just north of Belmont Avenue that had become a chokepoint for rail service, according to the CTA.

The bypass improves service on the three train lines by allowing the Brown line trains to pass over the Red and Purple line tracks, rather than crossing in front of the them, according to the CTA. Previously, trains on the three lines regularly had to stop and wait for each other to cross the junction.

Since the bypass finished, the CTA began the next phase of its modernization project, which involves demolishing, rebuilding and realigning the 100-year-old Red and Purple line tracks between Belmont and West Cornelia Avenue, which contain a curve that slows train speeds.

The CTA completed the soaring Belmont Bypass, and is now working on the tracks that run under it, including straightening the slight curve in the distance. Credit: Facebook/CTA

Phase 1 of the Red and Purple Modernization project includes three major components, including the Red-Purple Bypass, which began work in October 2019.

The project includes reconstructing the Red Line’s Lawrence, Argyle, Berwyn and Bryn Mawr stations so they’re larger and 100 percent accessible, according to the CTA. That work began this spring and should be finished by the end of 2024.

For the last major component of Phase 1, the CTA will install a new signal system on 23 miles of track between the Howard and Belmont stops, which will improve train flow and service reliability, according to the CTA.

More information on the Red and Purple Modernization project can be found on the CTA’s website.

Jake Wittich is a Report for America corps member covering Lakeview, Lincoln Park and LGBTQ communities across the city for Block Club Chicago.

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