The Tastee Diner lives on after 80 years while the Bethesda, Md., neighborhoods surrounding it get increasingly swankier. (Bill O'Leary/The Washington Post)

Bethesda’s Tastee Diner, with its weathered barstools and wooden booths, has offered its customers consistency for nearly 80 years.

The rail-car diner, a neighborhood landmark, promises comfort food, friendly service and table-mounted jukeboxes that steal a quarter every now and then. Its customers include a cross-section of Bethesda, from the late-night bar crowd to young families to seniors.

But Tastee’s, as it is affectionately known, finds itself in a rapidly changing Bethesda. In 2012, a $150 million mixed-use construction project aimed at bringing condominiums, apartments and 40,000 square feet of commercial space to downtown got underway. The development plans have highlighted the demarcation between “old Bethesda” and “new Bethesda.”

Many of the discussions about the development have taken place at Tastee’s as diners wonder what Bethesda is becoming and whether a 24-hour diner that opened its doors in 1935 can survive.

For Tastee Diner manager Beth Cox, 56, it’s tough to love today’s Bethesda. The area is becoming more like Georgetown, she says — “very trendy, very suburban and very upper class.” Cox is a lifelong Bethesda resident who grew up on Middleton Lane. She took over as the diner’s manager five years ago after a 20-year stint as a waitress and cashier.

Mary Thorne, 89, right, looks out the window during lunch at the diner. (Bill O'Leary/The Washington Post)

The typical customer’s bills average about $8, and Cox worries about where such diners fit in among the growing chain restaurants and upscale dining offerings.

“We don’t make a fortune,” she said, taking a seat recently at a faux-marble table during a lull in the morning rush. “We barely pay the bills. And it’s scary. Real scary.”

Montgomery County Council member Roger Berliner (D­Potomac-Bethesda) agrees that Bethesda has turned into “a more urban node” and become especially attractive to developers. But he said the County Council “takes historic preservation very seriously” and considers the Bethesda community to be quite active in the planning process.

Above all, Berliner says, the decision to innovate or hang onto older institutions is in the hands of residents, and many welcome the changes. “There are those who mourn the loss of Bethesda the way it was,” he said. “There are those who embrace the Bethesda that there is now, and there are those looking forward to the Bethesda of the future.”

There also are those who say the county’s development policies for the community are outdated. The Bethesda Central Business District (CBD) Sector Plan, a nonbinding set of recommendations and guidelines compiled by the Montgomery County Planning Board and used to gauge redevelopment in specific areas, was last revised in 1994.

A 2006 amendment to the plan was intended to boost business in Woodmont Triangle, a seven-block slice of northern Bethesda that is home to the diner. Among the stated goals is to “retain the qualities and ambiance of the small-scale retail that distinguishes the study area from other parts of the Bethesda CBD.” But many say the plan has had limited success. According to the Planning Board’s Web site, an update is underway.

John Pojeta, 78, and his wife, Mary, 77, are regulars at the Tastee Diner. They visit every weekend for breakfast, always ordering the same thing: bacon, eggs and sausage. Mary, a 1955 graduate of Bethesda-Chevy Chase High School, laments that Bethesda seems to have lost its small-town charm. “The diner is the one thing that seems like old Bethesda,” she says. “A lot of these places,”John adds between bites of scrambled egg, “have just disappeared.”

Young customer Spencer Gorman, 10, chats with the cook during a visit to the diner. (Bill O'Leary/The Washington Post)

Another diner regular, Andrew Mainz, a 13-year resident of Chevy Chase, sees development in Bethesda as a natural progression that meshes well with existing institutions, including Tastee’s. “I don’t think there’s anything wrong or right about it,” he says.

There’s been a spike in apartment and high-rise construction, but Bethesda, says Mainz, “has still got everything everybody needs — you’ve got your drive-through, your barber shop, your Safeway, your Metro and your diner.”

“Are you behaving?” Cox asks Mainz on her way down the aisle, a plate of toast and eggs in hand. “Yes, Mama Bear!” he replies. “She’s like the director,” he says with a laugh. “We’re all just the actors.”

Even with the influx of young, affluent families who create a breeding ground for what Mainz calls “overly corporate, overly franchised, cookie-cutter” businesses, the diner will always have a home in Bethesda, he says. Thanks to its staff, Mainz adds, “they’ll weather the storm.”

The diner has done it before. In June 2002, an electrical fire caused about $500,000 in damages and shuttered Tastee’s for nearly 100 days.

While Cox sat in the same booth every morning nursing the diner’s recovery with construction workers, customers gathered outside in a show of support, some with envelopes of money to help fund repairs.

According to Ken Hartman, director of the Bethesda Chevy Chase Regional Service Center, a de facto town hall and liaison between the community and government, nearly 3,000 housing units are slated for construction in and around Bethesda over the next five years. But he’s not worried about the area losing its remaining mom-and-pop businesses. “You’re going to see a lot of Bethesda that’s a hybrid of old and new,” he says.

Every weekend, Hartman sheds his business attire for a more casual look and takes a trip through downtown Bethesda with his wife and kids. Their breakfast destination? Tastee Diner.

“Tastee Diner continues to be a staple,” he says. “It’s not pretentious. There’s character in there. It has a certain niche in this market.”