The Chicago Transit Authority will begin field work July 24 to replace the nearly century-old Purple Line viaduct at Church Street in Evanston.
Because of the viaduct’s deteriorated condition, trains must reduce speed when crossing it. The replacement is expected to improve travel time for Purple Line riders.
Purple Line service will continue to operate during construction, but may be suspended for a limited time when the new viaduct is rolled into place in early October. Last year, when CTA replaced the viaduct at Main Street, Purple Line service was suspended for one weekend and bus shuttle service was provided as a substitute.
The project involves replacing the concrete viaduct with a new steel structure, as well as new abutments, retaining walls, foundations, and new waterproofing and drainage systems. The project also calls for rail tie replacement, new landscaping and lighting enhancements under the bridge.
The construction area will be located on the west side of Benson Avenue, north of Church Street. During the course of the construction, Church Street will remain open but will be reduced to one lane of traffic.
Benson Avenue will be reduced to one lane of traffic each way. Most of the parking on Benson between Church and Clark will be eliminated to allow traffic to continue to flow both ways. Access to local businesses will be maintained.
At its April meeting, the Chicago Transit Board approved a $3.3 million construction contract to replace the viaduct. The Church Street structure is the second of six Purple Line bridges the CTA is replacing as funding becomes available. The CTA and the City of Evanston worked together to identify the Church Street viaduct as the next in line for replacement.
CTA used Illinois FIRST funds for the replacement of the Main Street viaduct; however, with the end of the Illinois FIRST funding source, CTA turned to its Federal Transit Administration Rail Modernization funds to pay for the Church Street viaduct. Illinois Constructors Corporation of Elburn was selected as the contractor through a competitive bidding process.
The Purple Line extends from the Linden station in Wilmette to the Howard terminal in Chicago where customers can make connections with Red Line and Yellow Line trains.
Purple Line Express trains operate Monday through Friday during morning and afternoon rush periods offering non-stop service from Howard to Belmont, then making all stops to the Loop. The Purple Line is the sixth busiest rail line in the CTA system, totaling 3,033,576 rides in 2005.