One of the Greenway’s most important caretaker organizations is celebrating its fifth (or wooded) anniversary, looking forward to improving one of Boston’s best-known parks even more in the years to come.

The Greenway Business Improvement District (BID) is an organization founded to give the Greenway a longer term financial footing, collecting income from surrounding property owners and using it to beautify public space. Its leadership voted in November to extend its mission another five years, clearing the way for further improvements to the Greenway’s accessibility and programming.

While the Greenway’s public space has existed since The Big Dig finished relocating Interstate 93 underground in 2004, planners remained unfulfilled with the park’s support structure. That culminated in a 2018 collaboration between city officials and A Better City, a planning and business nonprofit that also traces its history back to The Big Dig.

All told, the Greenway BID covers 17 acres of public space downtown, with a budget of $17 million over five years. $1.1 million of that goes toward maintenance annually, with the rest saved for projects to improve the park.

The BID was really focused on being a helpful partner to the city and the Greenway’s conservancy,” said Rick Dimino, who serves as both the Greenway BID’s executive director and the president and CEO of A Better City. “It was clear that the operating capital requirements of the Greenway needed another leg of the stool to support its operation and maintenance.”

That money comes from the surrounding property owners. BIDs are essentially a regulated addition to the standard tax process, taking some money from the surrounding area each year and adding it to a dedicated fund to improve their territory.

BIDs remain relatively rare, with just three operating in the Downtown.

In the years to come, the Greenway Bid has a range of improvements planned for its park. Much of that will be lighting improvements to Dewey Square and the pathways around it, as well as its rotating mural exhibitions. Funding is also set aside for events to attract people to the Downtown after the pandemic dealt a body blow to tourism.

The most recent five-year plan increased the operating budget by $100,000. According to Dimino, that’s largely to offset inflation.

“The Commonwealth is putting in more money, the city is putting in more money, and the conservancy is being asked to raise more money because of good ol’ inflation. Things cost more as time moves on, and so we have to put more into the operations and maintenance budget,” he said. Smooth sailing isn’t guaranteed for the BID’s operations. Because the group’s income is based on tax assessments, if Boston’s property values drop it could eat into the BID’s budget. Real estate firms have expressed consistent confidence in Boston’s continued growth, but it’s still something Dimino is keeping an eye on.

“There are some headwinds for commercial properties nationwide because of the pandemic’s changes to office dynamics. That’s a yellow flag that all BIDs will need to look at, because if values come down that could pose some risk to the BID collection process,” he said.