The Chicago Transit Authority’s first new transit station in 15 years takes advantage of modern design techniques to incorporate as much glazing as possible, offering stunning views for riders and employees. Courtesy of Kate Joyce Studios
Transit service on Chicago’s famed El line to a neighborhood in transition will be provided via a modern, glass-enclosed station that offers stunning views of the city.
July 10, 2012—In recent years, the Chicago Transit Authority and the Chicago Department of Transportation have spearheaded a series of much-needed renovations to stations along the city’s venerable but aging elevated (El) system. But the recently opened Morgan Station on the Green Line represents the first brand new CTA station in 15 years. Nestled between Chicago’s Loop and the United Center sports stadium—roughly three-quarters of a mile in either direction—the $38-million station belatedly provides new transit service to a neighborhood, the West Loop, that has seen meteoric growth in recent years.
This semi-industrial stretch of Chicago, known for its lofts, meatpacking operations, and slick restaurants, gave designers a chance to fashion a striking glass-and-steel station that continues the city’s tradition of spare, “revealed” structures in which the structural underpinnings of a building become, in a manner of speaking, its ornamentation.
Many stations on the Green Line, which serves the city’s west and south sides, are built with fare collection equipment on the platform, so riders take a staircase up from the street to the track level, pay the fare there, and then board. Fare collection equipment is often on only one side of the station; travelers have to cross a bridge over the tracks if they need to reach the opposite platform.
The narrow station was squeezed into a space formerly occupied
by parking spaces, yet still provides access to fare equipment at
the ground level, easing passengers movements. Courtesy of
Kate Joyce Studios
But that layout inconveniences outbound travelers, and more equipment on top means greater loads for the building to support. What’s more, says Ryan Giblin, AIA, LEED AP BD+C—the project manager of Morgan Station for Chicago-based Ross Barney Architects—because Morgan Street carries a great deal of truck traffic, a new station couldn’t be located lower than 14 ft 6 in. from street level, which made a mezzanine approach, similar to other stations in the Loop, unfeasible. Furthermore, building the station at platform level was not as cost efficient as building it at grade.
So the architects at Ross Barney came up with a way to use what had been a parking lane in front of a sidewalk to create a station with two fare collection entrances at ground level, one on the north side of Lake Street and one on the south. Each leads up to separate platforms. (A bridge still connects the platforms above the tracks—the Morgan Station also serves the CTA’s Pink Line.)
The dual entryways gave the architects a chance to create a glassy, visually striking station design. Giblin says that Ross Barney’s design principal, Carol Ross Barney, FAIA, wanted to improve riders’ experiences with the system. “Carol’s main goal is to lighten these things up and make them pleasant places to be,” Giblin says.
“It is very different from any current CTA station,” adds Michael Lev, P.E., a vice president of TranSystems, the engineering consulting firm on the project. “It’s designed to look modern, [but] it takes its architectural inspiration from the surrounding area, [which] is a traditional, heavy commercial area—the Fulton Market area. A tremendous amount of meatpacking, warehousing, and a lot of food gets transferred through this part of town. It’s a very utilitarian area.”
The architects sheathed the upper floors of the station in metal
with an irregular pattern of holes that reveals the same geometric
pattern that can be seen when sunlight shines through the
El tracks onto ground below. Courtesy of Kate Joyce Studios
The glazing opens the station up visually and allows the station attendant to see what’s going on at both entrances. And because the station came in under budget, the Chicago Department of Transportation, which oversaw the project, gave the go-ahead to a plan to clad the overhead bridge with glass rather than perforated steel. The result is an extraordinary view of the towering skyscrapers of the Loop.
The architects sheathed the upper floors of the station in metal with an irregular pattern of holes that cleverly reveal an image—the same image that can be seen when sunlight shines through the El tracks to create a geometric play of shadows on the ground beneath. “If you look at the side of the building, vertically it has the look of what the shadows look like on the ground,” says Lev. “That was pretty cool.”
Among the challenges faced by the engineers on the project was that the new station had to be built on top of a working train line. Train traffic was maintained the entire time that the Morgan station was built—but the most critical work was done when trains were not in service, from 1:30 AM to 4:30 AM.
“When you’re building a station, you’re going to increase both dead load and live load on the structure,” says Lev. The additional loads, he says, include the platforms themselves—5 in. of precast concrete, 400 ft long and 10 ft wide—as well as passengers, wind loads, and, this being Chicago, snow loads. The designers also had to include the loads placed on the platform by CTA equipment.
The first order of business, Lev says, was to assess the strength of the existing structure to support these new loads. “Generally speaking most of the system dates back to late 1800s, early 1900s—they weren’t engineered to exactly what was necessary,” says Lev. “Some were overengineered. But some trains have gotten heavier.” What has proven typical in older systems such as Chicago’s is that, while there’s a bit of excess load capacity, there’s usually not enough to do anything major. You can add new signals or equipment, but anything heavier requires shoring up the existing foundation.
This was the case at the Morgan Station location, so the columns holding the train tracks up had to be replaced and fortified. Because the train lines continued to move, engineers had to build a shoring tower, a giant structure that temporarily supports the tracks as columns are replaced. In all, 20 separate columns were replaced, two at a time. In addition, engineers inserted micropiles—thin metal piles typically 6 in. or so in diameter—around the columns to provide additional support.
Despite the foundation work on the tracks, the station itself—just 15 ft wide and 45 ft long—is built on a separate foundation. Lev says, “You’ve got a building that’s going up that’s 10 feet away from train traffic. Having a separate building isolated vibrations from one structure to the other. It allows you some space to put up some protection.”
The columns supporting the train tracks had to be replaced or
fortified, two at a time. Some columns had micropiles added
around them to provide additional support. Courtesy of Kate
The CDOT went along for the ride with a minimum of handholding. Laura Saviano, the marketing principal for Ross Barney, credits that to Carol Ross Barney. “It’s such a grand gesture. Carol has been around the block so many times with these folks. She’s really good at getting buy-in from folks to move a good, important project forward.”
Apparently the CDOT was satisfied with the work; they’ve hired Ross Barney to design another brand new station, this one at the southern edge of Chicago’s South Loop at Cermak Road near the giant McCormick Place Convention Center. And the timetable for the $50-million project, which is just beginning initial planning, is even tighter: The city wants the project complete by the end of 2014. While Ross Barney spent 18 months on the design of Morgan, they’ll only have seven or eight on Cermak. “It’s fairly aggressive,” says Giblin.
What’s more, the CTA is planning another pair of ambitious projects on the south side. The first is a $425-million reconstruction of the south branch of the Red Line, the city’s primary’s north-south transit line. The south branch was first opened in 1969 down the median of the Dan Ryan Expressway. According to the CTA, some 80,000 people use the Dan Ryan Branch each day, but 40 percent of the branch requires trains to navigate slow zones. Instead of rebuilding the line while the trains stayed in operation—a four-year project—the CTA will close the south branch of the line and its nine stations and finish the work in five months. Crews will replace ties, rail, third rail, and ballast. Three stations along the system will also be brought into ADA compliance with new elevators.
When that project wraps up next fall, the CTA will begin a $240-million rehabilitation of the bus/rail terminal at 95th Street, the southern end of the line. Preliminary renderings suggest another glass-enclosed, contemporary-looking design, though no official designs have been released yet. Construction is likely to begin in 2014.
Giblin sees it all as a sign that the city’s transit system is moving in the right direction. “I think there is definitely a priority on providing good public transportation,” he says.