CTA’s Track Modernization Efforts Result in Lowest Slow Zone Levels Since 1997
Since 2011, Mayor Emanuel’s historic investment in upgrading and modernizing the system has led to the significant reduction of slow zones systemwide. Through multiple, major improvement projects – including the 2013 Red Line South Reconstruction Project and the recently completed Purple Line Express Improvement Project – CTA has continued to work to improve speed and reliability of service to customers across its system from neighborhoods to the downtown Loop.
Slow zones – areas where trains are required to operate at slower-than-normal speeds, some as low as 15 miles per hour – develop along track infrastructure due to age, regular wear and tear, extreme weather conditions and other factors. Slow zones not only affect train speeds but also the reliability and comfort of service for customers.
The most recent slow zone improvement projects have lowered travel times between two to five minutes per trip on average, or four to 10 minutes for a round-trip, depending on the time of day.
“Slow zones inhibit our customers in getting from point A to point B in an efficient, timely and comfortable manner,” said Mayor Emanuel. “Since 2011, we have continued to make important investments to maintain and improve the rail system and provide Chicagoans with a 21st century transit experience.”
“A critical part of providing safe and reliable service is by continually and properly maintaining our infrastructure,” said CTA president Dorval R. Carter, Jr. “Through an unprecedented number of investments across our system, including the recently completed Purple Line Express Track Improvement Project, CTA has continued to improve both the speed and reliability of service to our customers.”
At the end of December 2015 only 5.5 percent of CTA’s 224.1 miles of rail track were currently designated as slow zones, the lowest level since December 1997. The total is down from November’s 8.2 percent and significantly down from a high of 22.4 percent in 2007.
Service reliability improvement projects
Since 2011, CTA has eliminated approximately 20 miles of slow zones across its rail lines through major track and infrastructure improvement projects. Some recent examples include:
- Ravenswood Connector Rehabilitation: approximately two miles of slow zones eliminated on Brown and Purple Express tracks between Armitage and Merchandise Mart
- Purple Line Express Improvement Project: approximately four miles of slow zones eliminated on Purple Express tracks between Lawrence and Jarvis—the largest such project along that stretch in more than 40 years
- Milwaukee Blue Line Track Renewal (part of Your New Blue): about three miles of slow zones eliminated on Blue Line tracks between Damen and Logan Square
- Red Line South Reconstruction: nearly 10 miles of slow zones eliminated on Red Line tracks between Roosevelt and 95th Street
- Green Line Ashland/63rd Branch track improvements: about 1.5 miles of slow zones eliminated on Green Line tracks between Halsted and Garfield stations
Trains operating through slow zones are forced to travel as slow as 15 mph in order to maintain safety. Slow zone elimination work typically involves replacing aging rail ties and tie plates with new ties and plates, or whole track replacement. In some cases, eliminating slow zones involves structural improvements or improvements to power delivery systems. When slow zones are eliminated, speeds can return to normal limits—up to 55 mph on a straight stretch of track.
Slow zone remediation: CTA’s ongoing efforts
While major track improvement projects have been critical to eliminating slow zones across the system, regular track inspection and maintenance work helps prevent slow zones from forming due to track deterioration. This work is done continually across the entire system, with maintenance work occurring regularly and often overnight to minimize any impact to service. Last year, overnight slow zone work removed more than two miles on the Blue Line’s Forest Park branch.
While work to eliminate slow zones continues, CTA is also consistently taking steps to prevent future slow zones from developing. In December 2015, CTA announced the Green Line West Track Renewal Project, a track improvement project scheduled to begin in April that will prevent imminent slow zones from developing along aging Green Line tracks between Laramie and Harlem/Lake stations.
