Scott G Winterton, Deseret News
Salt Lake City was top of the list for transit access of the metropolitan workforce in 90 minutes or less.

Public transit is a critical part of the economic and social fabric of urban centers. In 2011 Americans took 10 billion trips on public transportation systems, according to the American Public Transportation Association. Almost all of these trips occurred in the nation’s 100 largest metro areas, which account for more than 95 percent of all transit passenger miles traveled. The Association notes that 60 percent of the people who use public transport are doing so to commute to and from work.

Given that transit is often used to connect people with their jobs, asking about how effective these connections are seems obvious. Yet until recently, very little information on this subject was available. A new study by the Brookings Institution sheds light on this topic, however.

For the study, Alan Berube, Elizabeth Kneebone, Robert Puentes and Adie Tomer analyzed data from 371 transit providers in the nation’s 100 largest metropolitan areas. They found the average urban dweller is unable to reach 70 percent of the jobs in their area via mass transit in less than 90 minutes.

Of course these numbers vary considerably by area, reflecting the diverging transit coverage, employment levels and decentralization. For example, 60 percent of jobs are accessible to residents of Honolulu in a 90-minute transit ride while just 7 percent of jobs can be reached in less than a 90-minute bus ride in Palm Bay.

They found that among very large metro areas, the share of jobs accessible via transit ranges from 37 percent in Washington and New York to 16 percent in Miami.

When researchers restricted their attention to jobs that require only low or moderate levels of skill, they found that approximately 75 percent of all jobs are unreachable in 90 minutes.

From the Brookings Institution briefing on this research:

"This reflects the higher concentration of high-skill jobs in cities, which are uniformly better served by transit. It also points to potentially large accessibility problems for workers in growing low-income suburban communities, who on average can access only about 22 percent of metropolitan jobs in low- and middle-skill industries for which they may be most qualified."

This spatial mismatch is not a trivial matter, according to Lucas Manfield and Christopher Wimer of Stanford University's Pathways magazine. "The poor can’t easily afford cars or the high costs of fueling and maintaining them. If we’re going to run a high-poverty economy in which cars are not available to all, there’s good reason to do a better job of making jobs accessible to the carless poor," they wrote.