Two CTA track inspectors wearing orange vests and hard hats walked along the Loop elevated structure looking for signs of trouble as they dodged passing trains.
The inspectors didn’t have far to go as they approached the Quincy station one day last week. It was one “L” of a mess.
There, just below platform level on the 115-year-old structure, sunbeams reached the street through splinters of badly decayed timbers and wooden ties that support and secure the steel railroad tracks.
The track’s two inner rails, which would come in contact with train wheels and stabilize the rail car only in the event of a derailment, were badly chipped and rusted, clearly in no condition to serve, as they once did, as the primary running rails.
To help keep the iconic Loop track going for possibly another 100 years, a $39 million track-replacement project is scheduled to start April 20 and continue primarily on 16 selected weekends through November, CTA officials said.
The renewal work, affecting about 11,500 feet of track, includes the stretch along Wells and Van Buren streets; a small portion above Wabash Avenue; the Hubbard Curve, just north of the Merchandise Mart station; and the junctions at Lake Street and Wells and Wabash and Van Buren, CTA officials said.
Lake and Wells is the site of Tower 18, one of the busiest rail junctions in the U.S., according to the CTA. On weekdays, an average of almost 700 CTA trains passes through the junction, where trains are directed either clockwise or counterclockwise around the Loop. About 500 trains serve the Loop on weekends, officials said.
About half of the total track on the Loop elevated is being replaced. The rectangle-shaped “L” is two miles around, double-tracked, resulting in four miles of track.
Standing on the platform of the Quincy station as the inspectors surveyed the tracks, Barney Gray, CTA general manager of construction, pointed to spots where the ties and supporting pieces weren’t as badly degraded as the worst of the timbers — not yet anyway.
If they all were that bad, the Loop “L” would be shut down, he said.
“Those rotting ties pose no immediate threat to the system. But what it tells us is that the other ties are not far behind in terms of deterioration,” Gray said.
The rehab work will be surgically performed in 50-hour bursts, beginning with rerouting of trains at 9 p.m. Fridays and ending before the morning rushes Mondays, officials said. It’ll be a tight schedule, with no margin for error because the tracks must be reopened by 4 a.m. each Monday, officials said. Five of the eight CTA rail lines travel on the Loop elevated.
As such, the project is being highly choreographed, almost down to the minute, to maximize productivity. About 350 workers will demolish and rebuild about 1,000 feet each weekend. Everything above the steel supporting structure and below the station platforms — rail, ties and track components — will be replaced.
Alternate service for riders, including rerouted trains in the Loop and shuttle buses, will be offered on those weekends.
But as a result of lessons learned during Loop track work in 2008 along the Lake and Wabash stretches of the elevated, disruptions are expected to be less severe this time, Gray said.
Replacement of all Loop “L” signal components was done during the 2008 phase, officials said. A new Tower 18 was also installed then, as was a new Tower 12, at Wabash and Van Buren. New systems installed then enhanced the CTA’s ability to regulate train movement, speed and intervals at the two junctions.
But the project to replace signal and train control systems didn’t go without a major hitch. Problems with the performance of the contractor, Divane Brothers Electric Co., delayed work until July, according to Chicago-L.org, a website operated by CTA staff. It was originally slated for completion in 2009.
The upcoming project, which is the first track work done on this portion of the Loop elevated since the 1980s, will conclude the major work needed for at least a couple of decades, CTA officials said. Some of the rail that will be removed dates to the 1920s, said Gray, adding that the supporting structure itself — dating to the mid-1890s — “is in good shape.”
“This work will create a more reliable ride for our customers and also address safety issues that could potentially result,” Gray said.
The project will start this month on the Wells leg of the Loop.
Driving in the Loop will be affected too. Rolling street closings will take place on some weekends on Wells from Lake to Van Buren during the work on the Wells stretch. The street must be cleared of vehicles to make way for cranes lifting sections of rail and other material into place, officials said.
The Van Buren portion of the elevated will be next, causing temporary weekend street shutdowns on Van Buren from Wabash to Wells, officials said.
Sidewalks will remain open, although the width of the pedestrian pathways will be narrowed and safety nets will be installed under the elevated structure, officials said.
The CTA will release an exact schedule once the project gets under way, said CTA spokesman Brian Steele.
The general contractor on the project is Ragnar Benson Construction. The $39 million project is state-funded. Even before work starts, the contract has grown from the $33.8 million approved by the CTA board last summer. The work is also off to a late start; it was set to begin in late 2011.
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