Some "creative" solutions to boost Red Line capacity could be presented in the next few months, according to MBTA officials who detailed Monday how even on-time trains during rush hour can be overcrowded.

"We are going to be looking at other ways that we can work within the existing system right now to make headway improvements, potentially a few other creative ideas that we're working on and will be presenting to the board in the next coming months," MBTA Chief Operating Officer Jeff Gonneville told reporters Monday.

MBTA Assistant General Manager Charles Planck told the T's Fiscal and Management Control Board that even when trains are at their optimal average of pulling into a station every 4.5 minutes during morning rush hour, the system is over capacity at several stations.

"We know that people are squeezing on," said Planck, who said others opt to skip crowded trains. The T has counted a train with 200 people on one car - about 20 percent above what the cars are designed to carry, he said.

Ridership on the Red Line has grown about 2 percent per year dating back to the introduction of Charlie Cards in 2008 and more reliable passenger counts, according to Planck. Weekend ridership growth on the Red Line has outpaced weekday growth, and Red Line ridership is growing faster than overall ridership on the T, according to Planck.

In a blog post last week, Frontier Group senior policy analyst Tony Dutzik wrote it is "surprising" that the T control board's December report to the Legislature described ridership growth as "basically flat." Dutzik wrote that Boston-area transit ridership grew faster between 2008 and 2014 than any of the country's other top 10 transit systems.

With 280,000 trips per weekday, the Red Line is the busiest line, accounting for about 22 percent of trips throughout the system, according to the T.

"We have overcrowding in all of our areas," Gonneville told reporters. He said, "Long-term capital investment is something that this presentation was to begin to set the stage on."

Planck noted an effort underway to address potential improvements to Red Line infrastructure.

"The signal system on the Red Line is predominantly a 1970s analogue-based, fixed-block train-control system," Planck told the control board. "We are preparing some cost-benefit analysis information about signal decisions that we may be able to present to you."

Gonneville said the "fixed-block" system limits the number of trains within particular geographical areas on the system.

The Red Line was among the hardest hit during last year's relentless snow and cold, and the Baker administration injected much of its $90 million winter preparedness spending into upgrades to rail infrastructure for the portion running outdoors.

With 54 miles of total track, 165 switches and nine miles of tunnel, the Red Line has a $1.5 billion state-of-good repair backlog. Overall, the T has a roughly $7.3 billion state-of-good repair backlog.

Planck said Red Line cars on average travel well above a 47,000-mile benchmark for distance traveled before a failure, though Transportation Secretary Stephanie Pollack questioned the basis for the 47,000 number.

Pollack also noted that an increase in on-time-performance - which is roughly 70 percent or higher - would expand capacity on the system.

For the un-rebuilt cars in a Red Line fleet constructed in the 1980s, the average distance traveled before failure is about 25,700 miles while the oldest fleet dating back to 1969 averages about 55,900. The newest cars average about 108,000 miles before a failure, according to Planck's presentation.

The MBTA is replacing the 132 cars dating back to the 1980s and earlier, with the Chinese rail giant CRRC on track with the procurement project, according to MBTA General Manager Frank DePaola.

Earlier in the month, Gonneville said shortening the time between Red Line train arrivals would require more than merely new cars combined with power and signal upgrades.

The state is currently rebuilding the Longfellow Bridge, which carries the Red Line across the Charles River between Cambridge and Boston.