Seattle's "one regional card for all" transit card. Courtesy of Flickr user Oran Viriyincy under a Creative Commons license.

Earlier this week, transit agencies in and around Seattle launched a new, two-tiered fare system: one rate for most riders in a region full of high-wage tech jobs, and another for those living on less than 200 percent of the poverty line.

The project — from the same city that last year brought us a $15 minimum wage, and a higher property tax to fund preschool for the poor — was designed to blunt rising inequality in the region, and it could aid as many as 100,000 low-income people there. Riders who qualify get a special "ORCA Lift" card for use on all of the region's transit systems that will automatically deduct $1.50 fares, as low as half of the standard rate on some services. A couple of other U.S. cities, including San Francisco, have tried something similar, but none has aspired to reach as many riders as Seattle hopes to. From the New York Times:

The distinctions start with scale and ambition: King County has about two and a half times San Francisco’s population, and in aiming for enrollment numbers San Franciscans could only dream of, it is relying on what transit experts say is the most innovative idea of all: tools honed by the Affordable Care Act. A countywide system of more than 40 health clinics, food banks, community colleges and other sites run by nonprofit groups was put together to enroll residents in health insurance, and those partners were re-enlisted in the last few weeks to start registering people for ORCA Lift.

To make matters even simpler, riders can verify their eligibility by showing that they've already qualified for other benefits like Medicaid, food stamps, or Temporary Assistance for Needy Families.

This kind of transit discount is one of the smartest subsidies any city can offer to the poor for a host of reasons. It's much cheaper — and politically more feasible — to enable the poor to commute to cheaper housing than to try to build that affordable housing in the expensive neighborhoods where many of them work. Transit is already heavily subsidized by public money, and this system directs that subsidy to the people who need it most. Improving public transit is also a tangible way to tackle unemployment among would-be workers who have a hard time keeping a job because they have a hard time getting to it.

A discount transit program is also, quite simply, a way to boost the incomes of the poor by returning more money to their pockets. If you spend as much on coffee as you do commuting every day, the difference doesn't sound like much. But it's the equivalent of a modest raise for people making minimum wage, even in Seattle.