The Greenway Conservancy is eyeing a second outdoor beer garden for the winding downtown park, this time across from South Station and a few blocks from where Trillium’s open-air canteen drew an estimated 100,000 people last year.

The nonprofit that runs the Rose Kennedy Greenway is releasing a request for proposals today for the so-called Dewey Square Drinkery, which it envisions as a pop-up style bar operating at least two days a week on Dewey Square Park Plaza.

The move follows the success of the Trillium Beer Garden last year across from Rowes Wharf. First pitched as a pilot, the outdoor taproom tucked along High Street far surpassed expectations, raking in about $150,000 for the nonprofit over a five-month span between fees and a revenue-sharing agreement it had with the brewery.

Officials on both sides said they expect it to return this year.

“We are in ongoing discussions with (the) Rose Kennedy Greenway team and anticipate returning this summer,” said Quin McKinley, a Trillium rep.

Conservancy officials say they’ll likely pursue a similar contract for the Dewey Square spot, though there will be key differences — including, most likely, a different operator.

The area already includes a twice-a-week farmers market, so any pop-up bar would be restricted to Mondays, Wednesdays, Fridays and weekends. And while it would likely open in May, it’s unclear if it would run through October, as the Trillium garden did last year.

According to the nonprofit’s RFP, it’s pitching an area along Atlantic Avenue, ranging from 3,300 to 5,000 square feet, with the goal of drawing from the 100,000 people who cycle through South Station on a daily basis.

“The Conservancy envisions a hybrid of commuters, young professionals, and tourists as the primary audience,” according to the RFP.

Bids are due by Feb. 20, and the nonprofit expects to pick a vendor by March 9.

Conservancy officials have sought to inject new revenue into the park amid years-long pressure from state officials to become more self-sufficient. Officials yesterday estimated that own-source revenue topped $1.1 million last year.

The Greenway signed a new 10-year lease with the state Department of Transportation last June to operate the 17-acre park, which included a combined $14 million in financing from the state, city and local businesses.

The agreement marked the first time the city and abutters agreed to help finance the park, which has long relied on state funds, plus its own fundraising and revenue, to satisfy its annual $5 million operating budget.