For decades, the District’s fight against the economic and social forces of gentrification has been a rear-guard action: belated restrictions on development, overdue attention to the needs of working-class families, modest affordable housing complexes tucked into neighborhoods where rent has already skyrocketed.

But a new initiative taking shape east of the Anacostia River aims to take a different approach. A nonprofit is buying property in a way that insulates it from development pressure, creating islands of affordability for longtime Washingtonians and girding against gentrification before the process begins.

The Douglass Community Land Trust, incorporated last month after years of planning and neighborhood outreach, will bring an increasingly popular approach to preserving affordable housing to the nation’s capital, which according to a recent study has experienced the country’s most intense rate of gentrification.

While the land trust has ambitions to expand citywide, its initial focus is on neighborhoods in Southeast where full-scale redevelopment and the accompanying displacement of longtime residents still seem like relatively distant prospects.

The Douglass Community Land Trust — named after Anacostia’s most famous resident, the 19th-century abolitionist and orator Frederick Douglass — is finalizing the acquisition of its first property, the 65-unit Savannah Apartments in Congress Heights.

“We have a chance now — east of the river and other places that haven’t yet experienced that kind of hyper-development that displaces folks — to create a plan,” said executive director Ginger Rumph.

That plan builds on a model that has been implemented across the country. Land trusts have been set up in very different places, from dense Eastern cities to coastal California farmland, with the common goal of preserving buildings or land that would otherwise be obliterated by the unfettered real estate market.

In their modern form, urban housing land trusts often operate through a model called shared equity housing. The trust buys and holds the deed to land beneath a building, leasing it back to a homeowner or developer, who owns the buildings.

Separating the land from the purchase price, in addition to other financial contributions made by the land trust, brings the home within the buying power of people with lower incomes — or, in the case of an apartment complex, makes it more economically feasible for a landlord to keep rents affordable.

In exchange, the building owner agrees to a limit on proceeds in case of a sale at a later date. That allows individual homeowners to reap some of the benefits of their investment while keeping the property affordable for future occupants.

Sen. Bernie Sanders (I-Vt.) put a spotlight on community land trusts when he included a proposed $50 billion to fund them in the housing plan released by his presidential campaign. Sanders championed one of the nation’s earlier and most successful land trusts as mayor of Burlington in the 1980s.

But the model dates back further: The first community land trust was founded in rural Georgia during the civil rights era to protect the livelihoods of sharecroppers, said Tony Pickett, chief executive of Grounded Solutions Network, a national group of land trusts.

Pickett said the trusts are becoming increasingly popular in cities with high rents and home prices, and they have an advantage over conventional affordable housing projects, which often revert to market rates after a set period elapses.

By contrast, land trusts keep housing affordable indefinitely. They hold particular promise, Pickett said, in areas where rising rents and development pressure can be foreseen, perhaps as the result of new parks, trails or public transit extensions.

In Atlanta, for example, a land trust has sprung up to offset the effects of the Atlanta BeltLine, a 22-mile loop of trails, parks and public transportation that is expected to drive up property values in some of the city’s historically African American neighborhoods.

“If we get in early enough, during the planning stages, before infrastructure improvements are implemented, maybe we can stem some of this displacement activity that occurs,” he said.

In the District, too, the idea for a community land trust grew out of a looming project that inspires mixed feelings.

That project is the 11th Street Bridge Park, an elevated public park, similar to New York City’s High Line, that is planned for the pilings of the old road bridge that once connected the Navy Yard and Anacostia neighborhoods. The park will span the Anacostia River and feature paths for pedestrians and cyclists, as well as ample park space and entertainment venues.

The projected construction, planning and permitting costs for the bridge, scheduled to open in 2023, will be approximately $74 million, some $38 million of which has been committed by the city. The rest is expected to come from private donors and through federal tax credits.

Southeast residents contemplate the project with both hope and suspicion.

“It’s impressive,” said Walter Riley, a public school teacher in Maryland who lives across the street from the Anacostia Metro station. “It also feels like, ‘Oh, they’re building something for the new residents of the community.’ ”

Kymone Freeman, managing partner of We Act Radio, an independent station that operates within view of the proposed bridge park site on Martin Luther King Jr. Avenue SE, said he wasn’t initially inclined to welcome the project.

“To be honest with you, I thought that it was an immediate threat to us,” he said. “I was against the idea originally, because it was going to usher in gentrification.”

That changed, Freeman said, after repeated conversations with Scott Kratz, the project’s director. Out of those conversations grew the idea for the Douglass Community Land Trust, Freeman said, and his own willingness to support the bridge park.

“Activists . . . often we’re very good at saying what we’re against, and not very good at saying what we’re for,” Freeman said. He ultimately agreed to be one of the organization’s founding board members, fulfilling another tenet of land trusts, where community members typically make up at least one-third of the governing board.

Kratz said bridge park organizers have held more than 1,000 community meetings and are undertaking various initiatives to dampen the potential effects of gentrification that could flow east of the river when the park connects Anacostia, one of the city’s poorest neighborhoods, to Navy Yard, one of its hottest redeveloped areas.

But the land trust’s activities have special urgency, he said.

“This isn’t just an idea on paper,” Kratz said. “The property values in Congress Heights are already going up. The property values in Deanwood are already going up.” More and more of those sales are cash-only transactions involving limited liability corporations, Kratz said, a harbinger of real estate speculation and impending development.

At the Savannah Apartments in Congress Heights, tenants board association vice president Tiffany Jessup said those pressures can be felt.

Blocks from the scenes of shootings this summer and dominated by low-slung brick housing complexes, the area seems remote from the prosperity that has washed over neighborhoods west of the river.

But change is apparent for those who pay close attention, Jessup said, as she walked in front of her building on a recent Sunday morning. While it is a few miles from the site of the planned 11th Street Bridge Park, the complex is a block from the Congress Heights Metro station and the campus of St. Elizabeths Hospital, which is slated for extensive redevelopment.

“Look at that white building,” she said, pointing to a structure down the road that showed signs of recent rehabbing. “Condos are being built everywhere. It was inevitable that someone was going to come and try to get this property and do whatever they want with it.”

But the inevitable hasn’t happened yet. A few years ago, after getting wind of an impending sale, Jessup, 48 — who grew up down the street — said she and other tenants exercised their rights under D.C.’s Tenant Opportunity to Purchase Act, which allows renters to make their landlord a competing offer before an impending sale.

At Savannah, the tenants joined with the nonprofit National Housing Trust, which purchased the property for approximately $7 million last year and is seeking financing for renovations. The Douglass Community Land Trust, which is contributing $1.3 million to the project, will hold the deed to the land beneath the buildings, with the goal of keeping the rental units permanently affordable.

Most units will be reserved for people making up to 50 percent of local median income, or about $61,000 per year for a four-person household. It would be the land trust’s first property.

Jessup said the deal would help her — and her parents, who have lived in the complex for 26 years — “be able to stay in a place that we have called home.”

Like Freeman, Jessup has joined the board of the community land trust. She said she hopes the building — which she said is being renamed the Savannah Preservation Apartments to reflect its new status as dedicated affordable housing — will pave the way for other homes to be kept affordable through the land trust.

But in a part of Washington where well-intentioned efforts have gone awry in the past, it will take time to see whether promises are matched by results, Jessup said.

“We would be their first, good and bad,” she said. “I guess we would be the guinea pigs.”