The next time a Metro meltdown makes you late for work, you may be entitled to a refund.

A new program, billed the "Rush-Hour Promise," would provide full refund credits to peak-period rail and Metrobus riders who encounter delays of 15 minutes or more — customers who are more likely than others to reduce their ridership or abandon Metro entirely, the agency said.

It's Metro's strongest appeal to riders who have grown weary of Metro's chronic reliability problems and have fled the system in droves. The rail system's average weekday ridership of 615,000 trips is down significantly from 2008 peaks of 750,000, with research showing at least 30 percent of the losses stemming from customers citing reliability concerns, according to Metro.

In board documents to be released Monday, Metro expresses concern that customers have been slow to return to the system after the year-long SafeTrack maintenance program. Furthermore, the agency says, "research shows that when a customer experiences a trip that takes 30 minutes or more than planned, they are significantly more likely to leave Metro entirely, or at a minimum, severely reduce how frequently they ride."

Metro General Manager Paul J. Wiedefeld said the program is an expression of the confidence the agency has in its ability to meet performance targets and provide reliable rush-hour service, while adding a measure of accountability for officials.

In the agency's most recent ­"Vital Signs" report, statistics showed that 88 percent of rail customers' trips were on time by last fall. The improved reliability comes after Metro retired its oldest and least reliable rail cars last year, and trimmed its operating hours while reducing service to expand overnight maintenance time and address budget concerns. While the changes help reduce wear and tear on the system, the agency also is running fewer trains, making performance targets easier to meet.

Metro estimates the refund program, which will run for the 2018 calendar year, will cost between $2 million and $3.5 million.

"We believe the needle is moving and it's moving in the right direction," Wiedefeld said in an interview. "But I think for the customer, they really need to feel that and understand that we're committed to it, and we're holding ourselves accountable, and we're willing to put something on the line to reinforce that."

Wiedefeld said the proposal, which the Metro board must approve, is a type of built-in security for riders who depend on the system for their daily commute.

"These are very big, complex systems and things do happen every day, but from a customer perspective what we're saying is in effect that we will get you to where you should be within 15 minutes of the schedule," he said. "We're trying to show you that we can be that predictable in our service."

Jack Evans, chairman of the Metro board, was enthusiastic about the proposal, hailing it as an accomplishment for an agency whose reputation officials have worked to repair since the January 2015 L'Enfant Plaza smoke calamity that killed 61-year-old Carol Glover and sickened scores of others.

"Essentially what we're saying is, 'If a ride takes you 15 minutes longer than it should have, you get your money back.' That's extraordinary — Metro's never done anything like that before," Evans said. "I think this is a reflection of the progress we've made in the last two years."

But riders who complain of persistent slowdowns, offloads and unexpected track disruptions may be surprised by the proportion of trips that would be refund-eligible under the program. In a four-month span from July through October, 285,296 Metro trips saw delays of 15 minutes or more, accounting for about 0.5 percent of trips overall during that period, according to the agency. Furthermore, customers must be using registered ­SmarTrip cards to receive a refund credit, cutting the pool of refund-eligible customers in half.

"If we're still making progress and we can come forward and say that we're at 90 percent of our trains on time now, then maybe 10 minutes would make sense instead of 15," Evans said. "Right now, 15's a good benchmark."

Despite the limited scale of the program, this past Wednesday's hectic evening commute serves as an illustration of how it could benefit scores of aggrieved riders. During the afternoon commute, a cracked rail resulted in single-tracking on the Blue and Orange lines, and truncated service on the Silver Line. Platforms were jammed with customers who endured extended waits, and some turned to alternatives such as Uber and Lyft.

Metro spokesman Dan Stessel said 3.48 percent of trips during the Wednesday afternoon peak period were delayed 15 or more minutes, which would have made 7,405 trips eligible for refunds if the "Rush-Hour Promise" were in effect. For the entire day Wednesday, 1.94 percent of the system's 405,443 peak-period trips would have qualified for refunds, Stessel said, adding up to about $32,000 in credits.

Rail customers with registered SmarTrip­ cards would see their refunds automatically credited to their accounts.

Here's how it would work: Customers traveling between two stations would be assessed a "MyTripTime" duration estimate. Those who fall 15 or more minutes outside the estimated trip window would get the full fare, between $2.25 and $6, credited to their SmarTrip cards. Unlike rail customers who would receive refunds automatically, bus riders would have to fill out an online form to request the $2 fare.

If the program is approved, Wiedefeld's staff will be authorized to develop terms and conditions — including measures to ensure people don't abuse the system.

Those who rely on passes, rather than stored value, would be refunded $3 for rail trips and $1 for bus trips.

Metro said refund-eligible ­cases include medical emergencies, police investigations, arcing incidents, smoke and fire, and other unplanned disruptions such as emergency track work.

But major capital projects, such as the upcoming crossover replacement that will close the Yellow Line's Huntington and Eisenhower Avenue stations in May, wouldn't be eligible for refunds. And neither would regional emergencies such as earthquakes or terrorist attacks, or major ­weather-related disruptions such as closures resulting from winter storms — announced well in advance.

And traffic congestion, the common cause of bus slowdowns, is not a refund-eligible factor: Rather, the program accommodates for late dispatches and mechanical breakdowns.

It's the second time in recent years that Metro has turned its attention to fares amid customer concerns about service. In July 2016, the agency implemented a 15-minute grace period allowing riders to enter and exit the same station without being charged as a way to remove penalties for those who might glance up at the wait times and change their minds. From July 2016 through June 2017, Stessel said, the agency issued about 625,000 grace-period credits, totaling about $1.13 million.

Metro issues some late-trip credits for customers using its MetroAccess paratransit program. If drivers arrive after a customer's 30-minute pickup window, the passenger receives two $3 late-trip credits, Metro said.

Wiedefeld said the new initiative for rail and bus customers is a benefit compared to what commuters who have turned to driving may experience on the roads.

"Tomorrow if you get on I-270 you may or may not have that predictability," Wiedefeld said. "You don't get a rebate — you deal with it."

The Metro board will consider the proposal Thursday at a meeting of its safety and service delivery committee. If approved, it will advance to a full board vote Jan. 25 and would be initiated Jan. 26, the agency said.

Asked why the program was limited to the 2018 calendar year and whether it could eventually be expanded, Wiedefeld called it an experiment.

"Like everything else we're doing, we want to try different things and we want to see how this works," Wiedefeld said. "Let's see how it goes from there."