Taxi driver Amanuel Gebrewold and other drivers are worried that a new private car service will reduce the number of fares from the Gaylord National Resort and Convention Center, seen here on May 31. (Mark Gail/The Washington Post)

Most of the passengers Etenesh Dembel carries in her taxi are guests of the Gaylord National Resort and Convention Center at National Harbor. But she fears that the work won’t last for long.

The luxury hotel in Prince George’s County is introducing a private car service this month for its guests, and that could mean fewer fares for Dembel and the other cabbies who flocked to National Harbor after it opened five years ago.

“This situation is terrible,” said Dembel, 32, an independent taxi driver who entered the industry about the time National Harbor and the Gaylord opened. “They are making it hard for us to survive.”

But the hotel says that guests have complained about the quality of taxi service, which prompted Gaylord to explore alternatives. Starting this week, the company that provides the hotel’s luxury “black car” service for guests will offer a less expensive option that uses hybrid vehicles.

Gaylord, the largest hotel on the East Coast with almost 2,000 rooms, says the taxis have not met the expectations of travelers. Guests have complained about language barriers, route choices and the unpredictability of the meter system, the hotel said.

“Our guests have expressed their desires for high-quality personal transportation service with clean vehicles, courteous and knowledgeable drivers and reasonable, flat-rate fares,” Gaylord National said in a statement.

The hotel’s transportation vendor, Veolia Transportation, will run the new hybrid vehicles, which will charge flat rates from the resort to destinations across the Washington region.

In a sprawling county with few large hotels, National Harbor has been a welcome hub for cabbies in search of steady work. Each day, between 100 and 200 taxi drivers serve the complex and its six hotels on the shores of the Potomac in Oxon Hill. But with Gaylord offering guests more alternatives, traditional taxi drivers say they are being squeezed out of National Harbor, which has been one of the county’s biggest economic engines since it opened in 2008.

The concerns have attracted the attention of labor unions, which are helping the drivers to lobby. “It was very lucrative for drivers to be able to pick up customers at the Gaylord. This was a hot spot for them. It was a way to make a living,” said Beth Levie, a Washington-based organizer for the AFL-CIO. “Now it is being taken away.”

Even before National Harbor’s opening, developers laid out rules for taxicab service. Cabbies were told that to operate there, they and their vehicles had to be clean and presentable.

For their part, taxi drivers have complained for years about their access to the Gaylord, saying hotel employees offer the luxury cars when guests ask for taxis. The cabbies are not allowed to park outside the hotel and are expected to wait on a parking deck across the street.

The conflict playing out in Prince George’s echoes the challenges facing the taxi industry in many metropolitan areas as drivers confront rising customer expectations and new technologies such as Uber, the smartphone app that can summon a car service.

In the District, officials have been under pressure to improve taxi service. Last year, the D.C. Council approved a package of major changes including requirements that drivers install credit-card readers and satellite navigation systems.

In Prince George’s, the taxi industry faces challenges particular to its geography. The county covers almost 500 square miles, so taxi drivers often roam far and wide for fares.

At the Gaylord, where a standard room starts at $229 a night, the black luxury sedans and SUVs parked outside are already taking away business from taxis, taxi drivers and union leaders say.

On a recent morning, when guests requested a cab, the doormen offered them the black cars. With no taxis right there, some guests took the more expensive black car. Only when a guest insisted on a cab did the doorman whistle for one.

Across the street, on the third level of a parking lot, a couple of dozen cabbies waited for business. They watched black car after black car leave the Gaylord with guests.

When the hybrids arrive, the taxi drivers fear that business at Gaylord will fade away.

“The rumor is that after a few weeks no more taxis will be working around here,” said Ammanuel Gebrewold, 29, a cabbie from Hyattsville.

Dwight Kines, a Veolia spokesman, said the company has no immediate plans to expand Express Transport to the other hotels at National Harbor. Rates will be competitive, Kines said. A trip to Reagan National Airport, for example, now $21 by taxi, will cost $26 during rush hour and $22 at other times.

“I don’t know that anybody is getting pushed out,” Kines said. “There will still be needs for taxis. Maybe not as much needs for taxis, but they are still there for when there are large checkouts.”

Neither the hotel nor Veolia would discuss details of their agreement, including whether Veolia is paying a concession fee to the hotel.

The Gaylord says that guests will continue to have the option of choosing a traditional taxi. But John Lally, an attorney who represents the county’s 16 cab companies, said that guests are likely to pick the option right in front of them.

“The men and women that drive Prince George County cabs are working people. These drivers are very entrepreneurial . . . and they give very good service,” he said.

Dembel, the cabbie, said she now spends more time roaming the streets of Prince George’s than waiting at National Harbor, where runs to the airport were worth a lot. Soon, she said, she will be back at the county’s Metro stations, competing for fares.

She recently invested $6,000 in her 2005 Crown Victoria, she said. She keeps the cab tidy. A large American flag sits atop the dashboard.

“I work 12 hours a day almost seven days a week so I can provide for my son,” said Dembel, who lives in District Heights and is expecting her second child. “Now it is going to be very difficult. It is going to make it very hard for me to make money.”