LOWELL — Bud Caulfield, 80, and Elmer Martinez, 20, are both Lowellians.
They went to the same high school, they live in the same neighborhood, and both have ideas of what Lowell should look like in the future.
But in big ways, the two men’s experiences and ideas are worlds apart. A one-time mayor and 12-term city councilor, Caulfield is a local political institution. Martinez’s mother, who cleans hotels for a living, moved to Lowell from Puerto Rico while pregnant with him.
“My mom’s Lowell and a city councilor’s Lowell — they’re two different cities,” said Martinez, a junior at Emerson College. “But it’s not one person’s more than another’s.”
These two experiences exemplify a divide that has emerged as the city finds itself at a crossroads, grappling with the question of what the former mill town should become.
Signs of Lowell’s heyday — the towering, red-bricked mills, the mural dedicated to textiles, the streetcar that still runs every day, the Merrimack River that once fueled it all -- still form the foundation of the city’s downtown, giving visitors the impression they’ve slipped into a bygone era.
So it can be jarring when the reminders that Lowell is in fact a modern American city punch through: the women walking down the street in hijabs, the Spanish music blaring from the idling truck, the African clothing shop.
The face of the city has fundamentally changed in the past few decades: Families like Martinez’s will soon make up the majority of Lowell, and foreign-born residents flocking from Cambodia, Brazil, and Nigeria for affordable housing and social service programs now make up more than a quarter of the population.
But to make sure that Lowell thrives in the future, Caulfield and others say the town needs economic growth, and that requires attracting new, affluent residents.
“You have got to look for balance. If you have nothing but [low-income] housing and little job training, you’re going to have chaos,” said City Councilor Bill Samaras.
The income divide is sometimes glaring.
The difference between the median annual incomes of the poorest and richest neighborhoods is about $40,000, but they’re separated by just one street. On the west side of Nesmith Street, shoddy duplexes and gas stations line the streets, and most businesses have signs in both English and Spanish.
Crossing the street is like entering another city; Federal-style architecture, neat lawns, and expansive driveways.
One of the leading visions among the politically powerful is some iteration of this: Lowell’s downtown industrial spaces will be developed into boutique apartments and shops to attract affluent residents who will move to Lowell and boost the city’s economy.
“You don’t want to come in and see a pawn shop; that doesn’t do anything for anyone,” Caufield said. “If you change the atmosphere, you can create businesses you can be proud of.”
At the heart of this proposal is the idea that the Hamilton Canal Innovation District, nearly a dozen parcels of land in the heart of the city, will be developed into commercial and residential buildings, expanding the downtown, solidifying Lowell’s tax base, and supporting “new local residents and employees.”
Teddy Panos, owner of the Athenian Corner, one of the city’s most popular restaurants, agrees that new development to attract residents with means is necessary.
“There needs to be a better mix of folks who have disposable income. The pendulum swung too far in the other direction,” said Panos, who is known as a tell-it-like-it-is morning radio show host.
“You can’t squeeze out folks at the lower end of the scale, but you have to create jobs, and we’ve had a lot of empty storefronts and revolving doors downtown.”
But this vision for Lowell’s future has some residents feeling left out.
“Are we going to forget about the majority of citizens who won’t be able to participate in that iteration of the American dream?” asked Martinez. “We’ve historically been a place for immigrants to acclimate and then strive for generational growth.”
Martinez said that there’s a sense among minority communities that a political elite that doesn’t represent them is “playing with the rest of our livelihoods.”
“You have leaders in the city who, while they’ve been around for a long time, are trying to impose their view of what the city should be on a majority population,” Martinez said. “It becomes problematic, because they can’t grasp the point of views of people from lesser means, of first-generation citizens coming from the poorer side of the tracks.”
Martinez, who hopes to one day raise a family in Lowell, said that he and his friends worry that the city in which they grew up will change.
This is not the first time that Lowell has had to define its future. In the 1980s, US Senator Paul Tsongas blew the dust off of the dying mill town. With his advocacy, the city created a series of institutions — a national historical park, a minor league baseball team, a robust higher educational system — that saved it from a fate some of its mill town neighbors have since suffered.
“We built an infrastructure, we made it happen,” and the town can do it again, Caulfield said.
But there are new tensions at play.
Yun-Ju Choi, executive director of Coalition for a Better Acre, a community development corporation, described an outsider-insider tension in the city.
“I don’t think there’s enough integration among different groups of people. We celebrate each other’s cultures, but it is not a real deep understanding of each other,” Choi said.
Many officials in Lowell push back against that narrative, and insist that “you won’t find a community that has opened their arms to immigrants” more. But Samaras concedes that just being welcoming isn’t enough, and he acknowledges the town has some blind spots.
“It’’s the difference between tolerance and respect,” Samaras said. “We still have issues where we don’t have translators at City Hall, and you see staffers just yelling at people.”
Those frustrations — a minority population that doesn’t see themselves reflected in the city’s halls of power — are at the heart of a federal lawsuit filed against the town in May, which argues that Lowell’s at-large election system dilutes the voting power of residents of color, in violation of the federal Voting Rights Act and the US Constitution.
“We don’t seem to have a voice on the City Council, and whenever we try to express concerns that are relevant and specific to our communities, it seems we are brushed off and sort of neglected,” said Daniel K. Uk, a 22-year-old graduate of Lowell High School and University of Massachusetts Lowell, and a plaintiff in the suit.
Robert Forrant, a history professor at UMass Lowell, said the “next big litmus test” for the future of the city is going to be how it resolves the lawsuit.
Samaras is optimistic.
“There’s always been an honest attempt in our history to try new things,” Samaras said. “There’s a resiliency in Lowell.”Catie Edmondson can be reached at catie.edmondson
@globe.com. Follow her on Twitter at @CatieEdmondson.