The four-year overhaul of the CTA Blue Line O'Hare branch will be getting underway a few months early, the transit agency will announce Monday, with sections closing over 10 weekends between late March and August.
CTA officials are asking riders to get on board with plans for temporary shuttle bus service, which is scheduled to kick off over the weekend of March 21 through the morning of March 24, when the California Avenue station will be temporarily closed for track work between the Western and Logan Square stations. The Western and Logan Square stations will remain open, officials said.
The CTA is conducting test runs of the free shuttle bus service in traffic to determine the best routes and to gauge travel times, CTA spokesman Brian Steele said. Riders affected by station closings should plan on anywhere from an extra 5 to 20 minutes, depending on their trip, he said. Free transfers will be provided from the shuttles back into open rail stations, Steele said.
Travelers going to O'Hare International Airport should budget the most extra time to ensure they make their flights, officials advised.
Nicknamed "Your New Blue," the $492 million project will dramatically improve travel times, reliability and customer convenience and enable the O'Hare branch to meet future ridership needs,'' said Carole Morey, CTA chief planning officer.
The branch is dotted with numerous slow zones that drag out the roughly 15-mile trip between downtown and O'Hare to about 50 minutes. The improvements, when completed at the end of 2018, are projected to shave up to 10 minutes off travel times each way, transit officials said.
Riders should begin experiencing better service by later this year on the elevated portion from near Logan Square throughDamen, said Bob Wittmann, CTA vice president of construction.
Construction-related rail service disruptions will not occur every weekend, but 2014 is poised to be a busy year, beginning with track work and followed by station rehab projects, officials said. The station work will begin at Western, Damen and California - the latter two dating to 1895. Improvements will be made at a total of 13 of the 16 stations on the branch.
"California and Damen are both historic, and we had to work very closely with the Illinois Historic Preservation Agency to make sure our design conforms with the historic nature of those properties," Wittmann said.
The project involves upgrading track, stations, signals and traction power and resolving water problems on the subway, elevated and Kennedy Expressway sections of the O'Hare branch.
The modernization is sorely needed on the project's 12.5-mile section between the Grand and O'Hare stations. Blue Line trains must reduce speed to as little as 15 mph, instead of the normal 55 mph maximum, on more than 21 percent of the O'Hare branch due to deteriorated track, according to the latest slow zone map, dated Feb. 17.
The CTA will invest about $180 million in new signals to help increase train speeds and provide the ability to run more trains, officials said.
"The signal system out there from Jefferson Park to O'Hare is the original from the 1980s. It will be replaced with the latest signal technology and make the whole system a lot more reliable," Wittmann said.
Turnback tracks will also be constructed at Jefferson Park and UIC Halsted to allow the CTA to short-turn trains during peak travel hours so it can tailor service to meet the heaviest passenger demand, officials said.
This year's work will be concentrated into one weekend in March, three in April, two in May and two in June, one in July and one in August. Some work will also be conducted during overnight hours on weekdays.
When the Blue Line project was announced in December, CTA officials said work was expected to start around June.
The O'Hare branch serves about 88,000 riders on an average weekday, about 56,000 riders on Saturdays and 46,000 riders on Sundays, according to CTA ridership reports.
The CTA plans to pack a lot of work into each weekend in which small sections of the Blue Line is cut. The first phase involves replacing wooden track ties, tie plates and other materials on the Milwaukee elevated track structure, between the Damen and Logan Square stations. The section opened in 1895, and the tracks still sit on the original structure.
Over seven weekends, Blue Line service will be suspended between the Western and Logan Square stations, officials said. Service will be halted between the Damen and Western stations over three weekends. The shutdowns will occur between about 10 p.m. on Fridays until shortly before 4 a.m. on Mondays, according to the project schedule.
The CTA is working with aldermen to complete details on temporary street closings and parking restrictions near the rolling work sites, officials said.
The $492 million project marks the most comprehensive overhaul since the branch was extended to O'Hare International Airport from Jefferson Park in 1983-84, officials said.
The O'Hare branch overhaul will be followed later by a modernization of the Blue Line's Forest Park branch, officials said.
Over about five months last year, the Red Line's south branch, between Chinatown and 95th Street along the Dan Ryan Expressway, was shut down for a complete track replacement and station upgrade project that cost $425 million.
"The O'Hare branch project is not an entire rebuild like Red Line South, but it will have the same type of benefits for customers,'' Steele said.
Other enhancements include the installation of wireless communications upgrades to support 4G service for passengers using mobile devices in the Dearborn Street and Milwaukee Avenue subways, officials said.
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