Putting Rapid back in Transit
At CTA, track renewal work continues in order to remove and prevent slow zones on the 'L' system.
Slow zones are areas where trains are required to operate at slower-than-normal speeds due to track conditions. Slow zone elimination work typically involves replacing aging rail ties and tie plates with new ties and plates, if not whole track replacement.
The end result of this construction is faster and more reliable service and a better, more comfortable commute.
(See the FAQ below for more about how tracks are laid.)
Slow Zone Maps
You can view the latest map showing where slow zones exist on the 'L' system (and archived maps, as well) on the Slow Zone Maps page.
Latest Project Information
Blue Line
Work will continue through 2009 and early 2010 to upgrade tracks and track ties in the Dearborn Subway. The Dearborn Subway, opened in 1951, is the downtown subway portion of the Blue Line, including all stations from Division through Clinton.
During 2007 and 2008, track tie replacement and other improvements were made to eliminate existing slow zones that were substantially impacting travel times. Using the resources available, construction crews focused on the sections of track that were in the worst shape. Many track components in the subway, including aging track ties, will be replaced in the coming months to provide even more reliable service in the future.
Dearborn Subway Project Overview
The $88 million project will result in the renewal of approximately 39,000 feet of track in the Blue Line Dearborn Subway. Funding is being provided by the Federal American Recovery and Reinvestment Act, and will create approximately 400 jobs over the course of the work (see Press Release).
This work will replace the remainder of older wooden track ties and replace them with new concrete ties to eliminate any remaining slow zones and prevent future slow zones. The goal of the project is to ensure better service and reliability, both now and in the future.
Work began in April 2009, with the bulk of construction occurring on weekends through the end of the year. On some weekends, trains may experience delays due to construction, or train service may be replaced with bus service for the portion of the route where construction is occurring. Some work will continue through the first quarter of 2010 with less customer impact.
Stay informed. Whenever work is being done, Customer Alerts will be posted on the 'L' system and online. We encourage you to plan ahead and check the Blue Line Route Guide's Customer Alerts section for both current and upcoming events affecting service.
Dearborn Subway Project Phase 1
The first phase of work will cover the portion of subway that runs under/along Milwaukee Avenue from its north portal, between the Damen and Division stations, through the area just south of the Grand station.
Included in this work area are the Division, Chicago and Grand stations. This work is expected to take place from mid-April through summer 2009.
Dearborn Subway Project Phase 2
Work will continue, replacing track ties and renewing track in the Dearborn Subway from south of Grand through the Clark/Lake station. This work will occur during summer and fall 2009.
Dearborn Subway Project Phase 3
During fall and winter 2009, work will occur in the area from Clark/Lake through the south portal of the subway tunnel, located between the UIC-Halsted and Clinton stations.
Update (12/09)—Work is progressing on-schedule and the project is nearing completion. Regular weekend closing of portions of the subway (with bus substitution service) has ended, and finishing work will continue in the coming months. There may be delays during work periods, which are generally scheduled to occur overnight and on weekends; look for Customer Alerts about work that may affect your trip online or at stations before you travel.
Dearborn Subway Project Map
This map shows the portion of the Blue Line where work will take place.
Other Blue Line Work
Additionally, CTA crews will renew three track switches, eliminating approximately 1,989 feet of slow zone on the O'Hare Branch by fall 2009.
CTA crews are currently performing work to eliminate 2,124 feet of slow zones near Damen on the O'Hare Branch. Work is scheduled to be completed in late Spring 2009.
More Information
See the Blue Line Route Guide for route information and all posted customer alerts for the Blue Line.
Red and Purple Lines: North Side Main Line (Belmont to Howard)
Work to eliminate slow zones on the North Side continues, including in the area of the Sheridan and Wilson stations, as well as on the express tracks from Belmont to Howard that are used by Purple Line Express trains during rush periods.
This work will continue throughout 2009 and will eliminate approximately 6,000 feet of slow zone on the North Side Main Line.
More Information
See the Red Line and Purple Line Route Guides for route information and all posted customer alerts for these routes.
Other Routes
As a part of regular maintenance, the CTA inspects, detects, and repairs conditions that might require slow zones.
What we've already done
As of April 2009, slow zone coverage of the system was down over 60% from October 2007 (from 22.3% of the system covered by slow zones to just under 8.1% as of mid-April 2009) after ambitious programs to renew and replace aging and deteriorating components of the 'L' system.
Already, we've completed slow zone elimination work as part of larger project zones, including:
- Red Line, State Street Subway in the area between north portal of the State Street Subway (north of North/Clybourn) and Roosevelt. Almost 3.5 miles of slow zones were eliminated until completion in 2008.
- Red Line, North Side Main Line from Howard to Belmont. Partial slow zone elimination was completed in 2008.
- Blue Line, O'Hare Branch between Addison and O'Hare. Track renewal and slow zone elimination work was completed in December 2008. Over 21 miles of track were renewed and over 18 miles of slow zones were eliminated.
- Blue Line, Dearborn Subway slow zone elimination between the Dearborn Subway's north portal (located between Damen and Division) and Clark/Lake. The first phase of work was completed, replacing over 5,000 deteriorated wooden track ties with concrete ties in areas where slow zones existed.
- Loop Elevated: Lake Street and Wabash Avenue sides of Loop. Slow zone elimination work was completed in November 2008.
- Brown Line, Ravenswood Branch from Southport to Western. Slow zone elimination completed October 2008 included major tie replacement work to eliminate slow zones through the elevated portions of the branch.
FAQ
Slow Zone Elimination
What goes into laying 'L' tracks?
Why are there slow zones on the 'L'?
Slow Zone Elimination
Q:
What goes into laying 'L' tracks?
A:
Railroads typically have two rails on which trains run, and are held in place by being affixed to track "ties." Ties can be made of wood, plastic or concrete. Tie plates are affixed directly to the track ties at a precise distance, and the rails are, in turn, are affixed to the ties by the tie plates.
The 'L' (like many other rapid transit systems) also has a "third rail" off to the side of the running rails, which is how electrical power is delivered to the trains.
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Q:
Why are there slow zones on the 'L'?
A:
Slow zones are created where train speeds are restricted to maintain safe travel. Commonly, this occurs in a section of track that is beyond its service life and in need of repair or replacement. Slow zones are also sometimes established temporarily in work zones over a period of ongoing construction work.
We take your safety very seriously, and continually inspect our railways for signs of deterioration. If track inspectors (or high-tech track-measuring equipment used for inspection) detect advanced wear or potential defects, a temporary slow zone may be put in place (or other, appropriate action taken), pending repair work.
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