RTD may ditch its higher regional fare for the N-Line when the commuter train to Denver’s north suburbs opens next year — part of an experiment aimed at boosting sagging ridership across the eight-county district while also testing the idea of one day charging a flat fare systemwide.

A Regional Transportation District committee will meet Tuesday to consider whether to move the concept — dubbed the Promotional Fare Pilot Program — on to the full RTD board of directors for a final vote next week.

The six-month initiative would eliminate the regional fare of $5.25 for a one-way Union Station-bound ride from the last two stations on the N-Line — Northglenn/112th and Eastlake/124th — and instead charge riders the local $3 price tag across the entire 13-mile line, regardless of from which station their trip originates.

After a lengthy delay, the N-Line is expected to debut next spring or summer.

“This is opening the door to a new way of looking at the relationship between fares and ridership,” RTD spokeswoman Pauletta Tonilas said Monday. “After the N-Line, the board could come back to see whether to apply it to another corridor.”

RTD has seen a steady decline in ridership on both its trains and buses over the last few years, dropping from more than 103 million boardings in 2015 to fewer than 98 million last year, despite adding three new commuter rail lines and a bus rapid transit route between Denver and Boulder — the Flatiron Flyer — in that time.

The conundrum with jettisoning the regional fare: Can RTD lure enough new passengers to account for the revenue that would be lost by slashing ticket prices for the system’s most distant riders?

RTD projects that it will lose $180,000 in fare revenue by eliminating the regional rate on the N-Line for six months. The agency projects 9,500 people will board the train per weekday during the first year of the line’s operation.

“What model of fare structure is useful for the future?” Tonilas said.

RTD’s current zone system is laid out so that a local $3 fare applies to trips that extend out 9.5 miles from Union Station (as the crow flies) while a regional $5.25 fare applies to trips further than that.

On the W-Line serving Golden, for example, that means all stations except for the end-of-the-line Jefferson County Government Center fall under the local fare. To the south, all stations on the C-Line and D-Line light rail trains except Littleton-Mineral and Littleton-Downtown are local.

On the N-Line, all but the last two stations qualify for the lower local fare under the current fare structure. Outgoing Thornton Mayor Heidi Williams, who has been critical of the N-Line’s delayed debut, lauds the idea of a flat fare in the corridor when it opens next year.

She said Thornton has no RTD bus service north of 120th Avenue presently, and her constituents have been waiting for their train for too long.

“There has to be some equity for folks in Adams County who have been paying (FasTracks) taxes since the inception of the tax” in 2005, Williams said. “It seems like they have to do something to incentivize people to get on the train. I mean five and a quarter each way — that’s a lot.”

RTD has been criticized for having fares that are some of the highest among transit agencies in the country, though the agency points out it also has some of the most generous discounts for low-income riders, students and seniors. The latest RTD fare increase went into effect less than a year ago.

If flat-fare revenues on the N-Line in the first half-year of service exceed what RTD is projecting under the current fare structure, RTD Board Chairman Doug Tisdale said, “it provides a template for further consideration” of the idea in other corridors.

“At the end of six months, this is not simply going on a shelf,” he said.

But applying a single fare across all of RTD’s buses and trains won’t be a quick or easy process, Tonilas said. There would need to be a full-scale analysis of how the change would impact low-income riders and how it would impact parking facilities at RTD’s dozens of stations.

She also said the last stop on the University of Colorado A-Line — Denver International Airport — would likely not be included in any flat-fare discussion. That station, whether as a starting or ending point, has the highest fare in the entire RTD system at $10.50 per passenger.

“We have to start with baby steps,” Tonilas said.