At a time of looming decisions on multiple mass transit proposals, a McKnight Foundation-sponsored synthesis of nine studies from the University of Minnesota's Center for Transportation Studies reaffirms the many economic and societal benefits of investing in transit.

Among the findings are that transitways significantly improve mobility and that development is occurring among new and emerging transit corridors. In fact, the studies state, even more money would likely flow if certain expansion and regulatory uncertainties were addressed by policymakers.

But the most compelling case is how mass transit can improve the lives of low-wage earners. This is a fact often overlooked in the unproductive political polarization that seemingly dogs transit debates here more than in many competing metro areas.

To prove transit's impact on low-income workers, the Center for Transportation Studies' Transitway Impacts Research Program (TIRP) took a look at the impact of the Hiawatha light-rail line, which was completed in 2004.

TIRP determined that in just a two-year period after service began (transit data from 2005, employment data from 2006), the number of low-wage jobs reachable within 30 minutes of transit travel jumped by 14,000 in light-rail station areas and 4,000 in areas with direct rail-bus connections. Further, the number of low-wage jobs around light-rail stations increased by about 5,000.

One study found that about half of light-rail riders could connect with buses, suggesting that for many public transit is inextricably linked to employment opportunities. And it's not just bringing workers downtown: The Hiawatha line, for instance, already spurs reverse commutes, with one-third of riders commuting outward.

And Hiawatha (renamed this year as the Blue Line) isn't just a job connector during rush hour. Data indicate that transit-dependent workers are much more likely to use transit at all hours to get to jobs.

At a time of rising income inequality — which can manifest itself into educational achievement gaps that have plagued Minneapolis and St. Paul — connecting workers to jobs is a goal that should undergird transit expansion.

This has been the oft-forgotten element of the highly charged argument about the proposed Southwest light-rail line. Sure, it would connect suburban workers to downtown Minneapolis jobs. But it would also bring lower-wage workers, particularly from planned stops in north Minneapolis, to the burgeoning, job-rich southwestern suburbs.

For example, TIRP cites the planned expansion of UnitedHealth's campus. More than 6,700 workers would be housed in facilities to be built along a planned Southwest light-rail station. In this case, as with so many others within the metro area, the potentially positive impacts for the entire region would be considerable.

Of course, jobs at all income levels need to meet the metro area's growing population — particularly at a time when the cost of commuting can approach the cost of housing, according to recently released data from the U.S. Bureau of Labor Statistics' Consumer Expenditure Survey.

That survey indicated that the cost difference between housing and commuting was $3,173 in 2007, but had narrowed to $462 in 2012. Individual cases will vary, of course. But nontransit commuting costs can hit lower incomes hardest, furthering the case for more transit options.

Transit also is essential for employers. For instance, one study reports that when employers are asked about transit access, they mention its role in their site-selection process more than any other factor. Expanded transit options are also frequently mentioned as essential elements for younger, millennial-generation employees when they choose a city to settle in. This is why so many similar-sized regions, like the Denver and Seattle metro areas, have aggressively invested in public transit.

Early next year in Minneapolis, a new mayor and a City Council that will have a majority of new members will contemplate the fate of the Southwest line, as well as other transit projects. Just weeks later, in St. Paul, the Legislature will convene and consider transit funding, among other issues.

Policymakers would be wise to remember that transit can be among the best investments in helping low-income workers, who in turn will better support their families.