It took years of saving, Ubaldo Montero said, but last year his family finally bought their own home, a brick house up against the Capital Beltway in the Forest Glen neighborhood of Silver Spring.

They didn’t mind the noise wall in the backyard, Montero said, and with the windows closed, they hardly hear the constant thrum of the eight-lane highway.

Then came the map from the Maryland State Highway Administration. It showed that a plan to relieve traffic on the notoriously congested highway by adding four toll lanes could require destroying the Monteros’ home and up to 33 others.

“We have a lot of thoughts about our future here,” Montero, 42, a carpenter, said on his front porch on a recent balmy spring evening. “One of our goals in our life was to have a house because we’d always rented. It’s bad to hear we might have to move again.”

Two weeks since the map showing possible toll lane designs was released, the potential impacts have begun to sink in and, in some cases, raise alarm.

In addition to taking as many as 34 homes and four businesses, adding toll lanes to the Beltway and Interstate 270 could require the state to buy strips of land, either permanently or temporarily during construction, from up to nearly 1,500 property owners.

People in nearly 4,600 homes, businesses, schools and other sites could potentially hear traffic at 66 decibels or higher — loud enough that having a conversation three feet apart would require raised voices, according to the study.

Some nearby residents say they also worry about the health impacts of more vehicle exhaust, and Montgomery County planners say they’d fight attempts to condemn adjacent parkland, which they say protects local streams.

“Nobody wants to lose their land,” said Kenneth Parker, 70, a retired federal worker who has a Beltway noise wall behind his home in Lanham, in Prince George’s County. “The Beltway is close enough as it is right now.”

It’s not unusual for governments to condemn homes and land when transportation officials decide the public benefits of widening roads or expanding transit outweigh the financial and personal costs of seizing private property. The state has the legal power of eminent domain to condemn property but must pay owners “fair market value.”

But not many interstates traverse such densely populated areas. When the Beltway was built in the late 1950s and early 1960s, the circumferential link around the nation’s capital sliced through suburbs that have continued to build up around it.

Maryland highway officials say the map with yellow dashes for homes that could be taken and red dashes to identify areas with increased noise are “very preliminary” and illustrate a worst-case scenario. They say companies that will compete to build the toll lanes will be rewarded for designs that spare homes and businesses, such as by tunneling or cantilevering some lanes over others.

No homes would need to be taken along I-270, though up to 234 pieces of land would need to be acquired, either permanently or during construction, the study found.

“At this early stage in the process, we have worked extremely hard to minimize the footprint and property needs,” said Lisa Choplin, the state’s director on the toll lanes project. “We will be incentivizing and prioritizing our private partners through innovation to further reduce these needs.”

Encroaching on homes

Maryland Gov. Larry Hogan (R) has said adding toll lanes is the only affordable way to alleviate crushing traffic congestion that stifles the economy, leaves motorists in daily misery, and continues to grow worse. In addition to mapping the potential property impacts, the study has found that motorists could cut 12 to 33 minutes off their future Beltway drive times, depending on where, when and how far they travel.

Some residents say they’re worried they would lose out under what the state has said would be a 50-year public-private partnership in which companies would design and build the new lanes in exchange for keeping the toll revenue.

But tunneling or cantilevering lanes would add costs and risks for a private partner, potentially eating into profits on a project that state officials say would cost $9 billion to $11 billion to build.

Most of the homes that the state study found might need to be demolished, depending on the design, are near Georgia Avenue, where the Beltway right of way is particularly narrow.

Sandra Patterson, 77, a retired librarian who lives a few doors down from Montero, said the Beltway was farther away when she bought her home in 1970. Over the years, she said, the state took half of her yard to widen the highway and built a noise wall 20 feet from her back sunroom.

She had planned to die in the home where she raised three children, she said, but now, “I have no idea what to do.”

“I’m not interested in moving,” Patterson said recently, pausing as a motorcycle roared past her backyard during the evening rush. “They couldn’t pay me enough. I like the area.”

Julie Quinn said “everybody is upset” in her Locust Hill neighborhood in Bethesda, where she and others who live along the Beltway are worried about more noise and fumes. When she bought her house 48 years ago, Quinn said, the Beltway was hidden and muffled behind thick trees. The state later cut down the trees and put up a sound wall against her backyard.

“I didn’t expect it to get closer, that’s for sure,” said Quinn, who operates a consignment store in the District. “I’m 85 and not really interested in moving right now. . . . The closer they get to me, my resale value goes way down.”

Not everyone who lives along the Beltway objects to it getting wider.

Grace Abong, 48, said she wouldn’t want to lose any of her yard, which backs up to the highway in Lanham. But she’s also tired of having to allow an hour to get to her caregiving job in Bethesda — a drive that she said would take no more than 30 minutes if traffic didn’t grind to a halt so frequently.

“I think there are things we have to sacrifice to make things better,” Abong said. “The Beltway needs to be widened.”

Noise and parkland effects

The red dotted line on the map showing which properties could hear more noise cuts through the cafeteria, gym and playground of Carderock Springs Elementary School in Bethesda.

Nearby residents who say they have been asking for a noise barrier for 20 years don’t want highway sounds or exhaust any closer to the school’s 370 children.

“Their bodies are growing, and their lungs are still developing,” said Karen Roman, the school’s former PTA president. “We want to keep pollutants away from their lungs as much as possible.”

Choplin said the state is investigating the possibility of a sound barrier for the school. Even so, she said, adding lanes doesn’t increase highway noise as dramatically as might be assumed. Even if traffic volumes double, she said, the overall noise increases by three decibels — barely enough for most people to notice.

The potential environmental impacts also are getting attention. Any widening could affect up to 45 parks and recreational facilities and require cutting up to 1,460 acres of woods, the study found.

Carol Rubin, special project manager on the toll lanes study for the Maryland-National Capital Park and Planning Commission, said the agency would object to the state taking parkland that protects streams feeding into the Potomac and Anacostia rivers.

When the Beltway was built through Montgomery County, she said, it incorporated parkway land that the commission believes it still owns. She said the commission also might argue that the state’s legal powers of eminent domain don’t extend to public land.

“We look at the parks as the lungs of the county,” Rubin said. “It’s what makes the environment breathe. It gives fresh air to the residents and to the built environment.”