Sondra Ferrell works at a sorting facility in Capitol Heights. Proposed cuts could eliminate 20 percent of the Postal Service workforce. (Bill O'Leary/WASHINGTON POST)

Dena Briscoe had not yet completed her senior year at Ballou High School when her stepfather drove her to the local U.S. Postal Service office to take the employment test. He was a letter carrier. Her mother had worked for the postal service, too, and her younger brother was hired there.

“It seemed like a secure job, because there was so much mail,” said Briscoe, who began working as a clerk in a Northeast D.C. post office in 1980. “When I first got there, the floor was just covered in mail.”

But now, the family business is in trouble.

There is a lot less mail these days, and job security is crumbling. Proposed cost-cutting measures that became public last week could eliminate 20 percent of the postal service workforce. The proposed cuts are the latest knock against a set of federal jobs that were once a trusted gateway to middle-class stability for families like Briscoe’s.

Across the nation, the postal service workforce has long reflected the makeup of America. The workforce is more than 50 percent white, 8 percent Hispanic, 8 percent Asian and 21 percent black, according to figures compiled by Philip F. Rubio, an assistant professor of history at North Carolina A&T State University who studies the postal service. Thirty-seven percent of its workers are female and about 1 / 4 are veterans.

In cities and small towns, postal jobs have long been respected jobs that could provide a stable income for a family. The American Postal Workers Union puts the average salary at $55,000.

“To get a job at the postal service meant an entrée into the middle class,” said Harley Shaiken, a professor who studies labor issues at the University of California at Berkeley. “For generations of Americans, it was the route to sending their kids to college, to having a decent life.”

For decades, the U.S. post service also was one of the nation’s largest employers, said Nancy Pope, the curator of postal history at the Smithsonian. The postal service employs 560,000, but the number is on the decline.

The appeal of postal jobs grew in 1970 after 200,000 USPS employees went on strike in protest of low wages and poor benefits. They won a 14 percent salary increase that year. By the 1980s, there were clauses banning layoffs, which guaranteed workers a job in the service even if their position was eliminated.

“It was the kind of job that, if you got it, you got to keep it,” Pope said.

In rural areas, being a postmaster was the next best thing to being mayor of the town. “It was the job to have,” she said. “And if you are a rural carrier, you know everybody's business.”

In urban areas, the jobs were especially important to African Americans, who were hired by the post office as early as the 1860s. Many major cities — including Charleston, S.C., Little Rock and New Orleans — had African American postmasters during Reconstruction, according to the National Postal Museum.

Later, the postal service was resegregated, along with the rest of the federal government. But between 1961 and 1966, the postal service became the single largest employer of African Americans in the country. Almost one out of 10 employees was black.

In research for his book, “There’s Always Work at the Post Office: African American Postal Workers and the Fight for Jobs, Justice, and Equality,” Rubio came across a rich history of stories, including those of black jazz musicians who worked for USPS. “They had a joke. They would say to each other ‘There’s always work in the post office,’ ” said Rubio, who was a letter carrier for two decades. “The idea [was] that it was a government job, and you could work there even if you could not get into a factory job” or if the jazz gigs were running dry.

“There was a tradition that is going to be lost,” he said.

The history of Briscoe’s family with the postal service is a familiar story among black USPS workers in the District. In 1960, 63 percent of postal workers and 14 percent of postal supervisors in the District were black, according to Rubio.

Briscoe’s stepfather worked in the postal service for 42 years. Her mother used it as a stepping stone and, after a few years with USPS, went to American University to study psychology.

But apart from her immediate family, Briscoe, who is black, said her co-workers became a kind of family. “I worked the night shift, and you end up seeing your co-workers more than you see your family,” she said. “We celebrated baby showers and all give a contribution when someone passes. We try to support each other. That’s why I love it. We like the work. We feel like we’re doing a service to a public.”

Alton Branson, a 56-year old letter carrier in Clinton, said he was drawn to the work for the same reasons. A brother-in-law and a mentor encouraged him to apply 37 years ago.

“I just felt there was a lot of pride in the job, in wearing the uniform,” said Branson, a single father who sent three daughters to college on a postal worker’s salary. “Back then, we had the police hats with the badges. That intrigued me.”

In time, the postal service stayed in urban areas as other employers moved out, said Gary Burtless, a labor market expert at the Brookings Institution. “They still have sizable pockets of employment in communities that do not have lots of other good jobs. These jobs have decent wages, good health benefits and vacation benefits.”

Fred Jones, who lives in Largo, was hired as a janitor at a post office six years ago. USPS was looking to hire veterans and that gave him a leg up. His father had worked there for 42 years — eventually becoming a supervisor. Jones’s plan is similar, despite the planned cuts.

“I’m here until I retire,” Jones said. “I’m not going anywhere. They are going to have to get rid of me.”

Staff writer Lisa Rein and news research editor Madonna Lebling contributed to this report.