While BART waits for its new trains to arrive, the region’s backbone transit system is wrestling to relieve overcrowding — rebuilding damaged and retired railcars, adding maintenance crews and pressing nearly every spare car into service.

But with so many passengers packing the system that train cars sometimes run out of room, BART is getting ready to try something different: using a mix of social media, gaming and cash as an incentive to get some BART riders to travel outside of the busiest parts of the commute.

A program known as BART Perks will be rolled out this spring with the goal of “nudging passenger travel times” from the heart of the commute to slightly less-crowded times. Enticing just 1,250 people — about the capacity of a 10-car train — to commute a bit earlier or later, officials said, could significantly reduce crowding on trains and station platforms.

The need to spread out the rush is growing. San Francisco’s downtown stations, particularly Montgomery and Embarcadero, have become so overwhelmed with arriving passengers in the morning that BART is planning to run all of its escalators in the up direction to clear platforms. Transbay trains are often packed to the limit, as most commuters have experienced.

BART’s ridership has boomed along with the Bay Area economy, with 430,000 trips on an average weekday — up more than 100,000 in five years.

“We’re far beyond any standards that BART has set” for rush-hour train capacity, said Val Menotti, BART’s chief planning and development officer.

A 6-month test

So BART, working with the San Francisco County Transportation Authority, is aiming to steer commuters into more breathing room. The six-month test, which could be extended or expanded, hopes to enlist 25,000 participants with automatic Clipper payment cards who will agree to let the program monitor their travel patterns.

Details are not yet available, but participants would earn points for changing their commutes from the busiest period — most likely to be designated as 7 to 8:30 a.m. — to an hour earlier or an hour later.

Riders could collect points in other ways, including by referring friends to the program, and then redeem the points for small and as yet undisclosed rebates. Or they could choose to play games with their points, gambling that their luck or skills at spinning a virtual wheel or playing a modified version of the popular Snakes and Ladders game will win them a $100 prize.

Menotti described BART Perks as a loyalty program melded with elements of gaming and social networking.

“It’s something we hope our passengers will find to be fun,” he said.

While any rider can participate, BART will target East Bay commuters bound for the busy downtown San Francisco stations. BART spokeswoman Alicia Trost said the agency was also talking with large employers near the Embarcadero and Montgomery stations about allowing their workers the flexibility to participate.

The $1.6 million experiment, funded mostly with grants from federal transportation agencies, is based on successful programs used on crowded transit systems in Singapore and Bangalore, India. Like those, BART Perks was developed by Urban Engines, a Silicon Valley startup focused on mobility.

Offering incentives is a new twist in efforts to shift when people commute. Some transit agencies, most notably Washington’s Metrorail system, have used peak-period pricing — charging higher fares during the busiest periods and lower fares at other times — to drive riders away from the rush.

BART Director Zakhary Mallett of Richmond has suggested the agency should consider charging peak-period fares, a practice known as congestion pricing. But BART has never seriously considered it, and Trost emphasized that BART Perks was not meant to be a step in that direction.

“This program gives money back to users,” she said. “It’s a reward — it’s the carrot approach. It’s not the stick approach, which is what most congestion pricing programs use. They charge you more money if you don’t change.”

Peak-period fares

Both the carrot and stick approaches are edging their way into transportation in the Bay Area and beyond. Fourteen of the nation’s nearly 200 transit agencies charge peak-period fares, according to the American Public Transportation Agency.

The Bay Area Toll Authority, in 2010, raised Bay Bridge tolls to $6 during the morning and evening peaks, while keeping them at $4 during off-peak hours. The region’s nascent network of express lanes charges tolls that rise and fall with traffic.

San Francisco adjusts rates at some of its parking meters so that they charge more during the busiest times and for special events. And planners working on a new version of the Clipper card have discussed enabling congestion pricing.

Michael Cabanatuan is a San Francisco Chronicle staff writer. Email: mcabanatuan@sfchronicle.com Twitter: @ctuan