Measuring growth by zip code

Twenty-five years ago, the Lansdale exit on the Northeast Extension was a drowsy interchange with four toll booths that opened onto an area of cornfields and factories.

Modernized and expanded, the Lansdale interchange now has 10 toll lanes - some with EZPass - that handle 12 million vehicles a year. And the Lansdale economy has been updated, too, with business services companies, retail strip plazas, corporate centers, and health-care facilities.

"There's a lot of new rooftops up here," Bob Wrigley, president of Trefoil Properties L.P., a commercial and retail developer with offices in the area, said last week. "It seems like there is a drugstore on every corner."

The Lansdale area is part of an outer-suburban belt that produced the most new jobs in the Pennsylvania suburbs since the mid-1990s, according to new data on job growth by zip code from the Metropolitan Philadelphia Indicators Project at Temple University.

This belt stretches from Kennett Square in southern Chester County to Doylestown in central Bucks County.

In South Jersey, Mount Laurel and Marlton had large employment gains, according to the data. The towns are farther-out suburbs, but on, or near, the New Jersey Turnpike.

In Philadelphia, areas around institutions, such as the airport and the University of Pennsylvania, also added thousands of jobs.

Twenty-one city zip codes gained jobs, and 26 lost jobs since the mid-1990s.

Older bedroom suburbs in Bucks and Delaware Counties in Pennsylvania and Camden County in South Jersey trailed the outer-belt suburbs and rejuvenated areas of Philadelphia.

The zip-code data confirm that the job markets in the distant suburbs have boomed, following residential construction in those areas. The information shows a highly fragmented labor market, one that increasingly is "arranging itself along major roadways," said David Elesh, an associate sociology professor at Temple University and a principal investigator on the indicators project.

The underlying information for the zip-code data comes from the U.S. Census Bureau for the years 1995 and 2004. The indicators project at Temple is being partially funded by $2.1 million from the William Penn Foundation, a nonprofit.

Steve Wray, executive director of the Economy League of Greater Philadelphia, said some experts have described the Philadelphia region as having "an exit-ramp economy." New office complexes follow highways, such as Routes 202 and 422 in Chester and Montgomery Counties, he said.

In some instances, the growth of the outer-belt communities has drained economic vitality from the suburbs closer to the city, as retail stores have moved to new areas, Wray said.

Sallie Glickman, executive director of the Philadelphia Workforce Investment Board, a government-supported agency, said new job-growth areas make it essential for workers to own cars, which is difficult for many lower-income city residents. "These counties will experience labor shortages unless people can find places to live close to their jobs," she warned.

Edge city is an urban-planning buzzword that describes office clusters on the outskirts of major U.S. cities. In this region, Conshohocken would be considered an edge city.

Conshohocken ranked among the top 20 area zip codes in job growth since the mid-1990s, with 6,400 new jobs.

The data from Philadelphia and other cities in recent years, though, indicate that many metropolitan areas are, in effect, "edgeless cities," Elesh said. Jobs are spread across many municipalities and office complexes.

Author Robert E. Lang popularized the term with his book by the same name, Edgeless Cities, published in 2003 by the Brookings Institution. The Philadelphia region is an edgeless city, with about 100 separate office clusters, according to the book.

"We're into total dispersion," said Arthur Nelson, director of the Metropolitan Institute, a think tank at Virginia Tech. The future of metropolitan areas will be belts and corridors of office employment in the suburbs, with a possible weakening employment in downtown office towers, Nelson said.

The popularity of city living is forcing a conversion of office space to condos, he said.

"They are shoving commercial out," Nelson said of new city residents. "We are only at the beginning of this commercial displacement." Philadelphia, Chicago, Toronto, New York, San Francisco and Washington are experiencing this pressure, he said.

In Philadelphia, the financial district and the surrounding area west of Broad Street lost thousands of jobs since the mid-1990s, according to the indicators project. It is in this area that the owner of Two Liberty Place, one of the city's tallest buildings, is converting one-third of the office tower to luxury condos. The area may have recovered some employment in the last two years with the rebound of the Center City office market, experts say.

Another part of town that saw substantial job losses was Old City, also a residential destination in recent years.

With an exception of a zip code rich in law firms, near City Hall, big job growth in the city followed a distinct pattern. It was driven largely by colleges, hospitals, the airport and the Convention Center.

One institution whose growth coincides with the years of the data is Drexel University, which hired Constantine Papadakis as president in 1995. When he arrived, the university had a boarded-up dormitory at 34th Street and Powelton Avenue, 8,000 students, and 1,500 employees on its 65 acres in West Philadelphia.

Since 1995, Drexel has boosted enrollment to 20,000 students, opened the boarded-up dormitory, built new dormitories, and expanded its main-campus staff to 4,000 employees. "We have added 12,000 students in 12 years," Papadakis said. "These are people who want to come to an urban school."

The zip code that includes the Drexel campus also contains the University of Pennsylvania. It had the highest employment gain in the city, with 9,900 new jobs, ranking it No. 7 in the region.