When it comes to CTA train sizes, which range from two to eight cars, riders forced to squeeze their way aboard even during non-rush hours are wondering about the long and short of it all.
The transit agency started reshuffling its resources last month to focus on decrowding trains during the height of rush periods when rail cars are packed to "crush loads." But commuters traveling at other times are calling for a break and a seat too.
The CTA system has plenty of excess capacity at midday, a time when extra cars are parked in rail yards. So why does the CTA operate four-car trains when passenger demand would seem to call for at least six-car trains?
"We aren't getting eight cars when we need them during the middle of the day," Brown Line rider David Dalka said.
It has been more than three years since the CTA completed the $530 million Brown Line capacity-expansion project that extended platforms to accommodate up to eight-car trains, replacing a six-car maximum. The project was aimed at improving service and customer comfort by easing crowded conditions.
Retired banker Jim Perry gets on a four-car CTA Brown Line train shortly after noon several times a week, and he often can't get a seat because of crowding, he said. Perry, a numbers guy, said he would love to understand the cost analysis that's behind the game of musical chairs the CTA plays with the number of cars hooked up to a train, and hours later decoupled and then again recoupled to match the swings in ridership over each 24-hour cycle.
"What is the cost benefit of keeping an eight-car train versus the manpower and energy costs of removing four cars after the morning and evening rushes?" Perry said. "Is it contractual with the unions? It seems that there should be some cost-savings with keeping the eight-car trains the majority of the day."
Several hundred dollars are spent or saved by adding or eliminating two or four 3200 Series cars per run on the Brown Line, which is the city's fastest-growing rail route, the CTA said. This year the Brown Line is projected to operate 114,000 round trips, officials said.
Systemwide, the CTA said it saves several million dollars annually by varying the length of trains over the course of the day. Running longer trains more often would rack up mileage more quickly, increasing the wear and tear on the cars, tracks and signal system, officials said.
The cost of running a four-car train from the Kimball terminal to the Loop and back to Kimball totals $324.75 on average, according to a CTA itemization of available expenses in 2011 that the Tribune requested. The cost increases to an average of $447.94 to run a six-car train and $571.12 to operate an eight-car train, the agency said.
In a cost-saving move, the CTA no longer operates six-car trains on the Brown Line, nor on any other lines during midday service, officials said.
Transit officials said five expenses comprise the total operating costs: electricity; rail car maintenance, which includes parts and labor for repairs; operator salary and benefits; indirect costs, which include coupling and decoupling trains, cleaning a rail station and maintaining facilities; and capital expenses, which include the wear and tear on rail cars, tracks, signals and power infrastructure.
Changing the size of a train requires at least three workers — one or two switch workers, a yard master and a lead switchman — to couple or decouple rail cars and move the train out of the yard to begin service, officials said. They could not provide a cost estimate of a sample coupling-decoupling procedure.
On the CTA rail system as a whole, to operate a train for an hour the operator accounts for about 31 percent of the cost; power, 19 percent; and maintenance, 50 percent, according to the transit agency. Power and maintenance costs are about twice as much for an eight-car train as they are for a four-car train, officials said.
In the Brown Line round trip example, operator costs, at $78.39, don't change, regardless of train length, while other categories increase in cost as the number of cars per train increases. The efficiency of electric trains is demonstrated in the power costs, which may surprise the average rider: only $29.03 for a four-car Brown Line train making the approximately 20-mile Kimball-Loop-Kimball round trip; $43.55 for six cars; and $58.06 for eight cars.
CTA officials said the breakdown is their best attempt to summarize expenses but it does not capture all costs. They cautioned against making comparisons based on the number of riders per car and the fares collected, even though a rough calculation would suggest there is adequate passenger revenue during some heavy ridership off-peak periods to cover much of the cost for longer trains. But actual costs would vary line by line based on the efficiency and maintenance needs of the different rail car models and on route distances, officials said.
While CTA officials said they are committed to providing service that is more reliable and comfortable, the economics dictate that a certain level of congestion is desirable from a business standpoint. CTA service standards are designed to offer enough capacity and frequent service — not to ensure there are plenty of empty seats and elbow room, transit officials said.
It means that as long as passengers are able to board a train, the supply meets the demand.
"We are unaware of any current off-peak service where trains are at maximum capacity and passengers are unable to board," CTA spokesman Brian Steele said.
During off-peak hours between the rushes and late-night and overnight hours, customers are better served by shorter trains that make stops more frequently — meaning shorter waits between trains — than by longer trains providing less frequent service, according to the agency's service standards.
"Under a fixed budget, increasing train lengths would mean a corresponding reduction in frequency to keep costs neutral," Steele said. "As long as the CTA is meeting passenger demand with a shorter train, CTA feels that this option provides better service to our customers due to shorter wait times for service."
The number of cars per train changes during the day on six of the eight CTA rail lines, officials said. Train lengths are constant on the Pink Line, which always operates four-car trains, and on the Yellow Line, which runs two-car trains.
A maximum of eight cars operates on the Brown, Red, Blue and Orange lines. Six-car maximums serve the Green and Purple lines.
On weekdays, longer trains begin service about 5:30 to 6 a.m. Trains are shortened after the morning rush for midday service and then lengthened about 1:30 to 2 p.m. for the evening rush, officials said.
The schedule varies by line for night and overnight service. Trains on the Orange, Green and Purple lines are downsized to four cars between 7 and 8 p.m.; the Red Line switches to four cars between 11 p.m. and midnight; the Blue Line converts to four cars at 10 p.m., and the Brown Line goes back to four cars at 9:30 p.m., officials said.
During rush-hour crush-loading conditions, 90 or more passengers are packed into a CTA rail car, according to the transit agency. The new goal under the decrowding plan that began Dec. 16 is 70 to 75 passengers per car, officials said.
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