The past few months have seen a slew of articles critiquing the common narrative proclaiming the renaissance of the city in America. In fact, only a small slice of the US population (the young, the white, and the educated) is becoming more urban. While those with the most economic and social capital move to the cities, everyone else is still moving into less dense, more spread out, and more car dependent neighborhoods. This trend has wide-ranging implications for how we administer social services to the poor.

Measuring a city’s ability to serve its low-income residents is notoriously tricky. Cities providing the fewest social services to their residents are often abandoned by those residents, leading to artificially low rates of poverty. Cities with robust safety nets often see the reverse effect. The difficulty of analyzing the effectiveness of these policies often distracts from a more fundamental question: Do cities have a unique ability to care for the poor by virtue of their density? The answer seems to be a resounding yes.

Here in New York City, representatives from Riders Alliance and others have been pushing for subsidized MetroCards. This is hugely important, as reliable access to jobs and services vastly increase the earning potential for lower income residents of the city. A subsidized MetroCard, or its equivalent, is much less effective at ensuring economic access in a less dense region without a sufficient network of public transportation options. What, in the suburbs, would a program like this look like? Subsidized car ownership certainly doesn’t make much sense. The result is often bleak: The Federal Highway Administration estimates that transportation costs consume 25% of the average family income in auto dependent areas, but only 9% of family income in denser regions. While the poor in every city are the most likely to use public transportation, public transportation is not an effective link the wider community in suburban areas built on the expectation of ubiquitous car ownership. A family is forced to choose whether they will be at the mercy of a stigmatized, ineffective public transit system or pump a quarter of their income into car ownership.

Similar arguments can be made for everything from soup kitchens to food pantries, from job training sites to homeless shelters. In areas where people are spread out, these social services don’t have the dense concentration of users that enable them to be cost effective. The effective, efficient provision of social services are dependent on density.

Mayor de Blasio’s Mandatory Inclusionary Housing and Zoning for Quality and Affordability plans have been the subject of intense debate. These plans have often centered on the issues of displacement and neighborhood ownership. With good reason, many have lamented that the city is becoming increasingly unaffordable and that the character of long established neighborhoods is at risk. Much ink has been spilled about rising prices forcing lower income residents to leave the city behind, and the potential impact of losing touch with the network and support system often attendant in neighborhoods. We have rightly lamented the loss of community, but we have not paid enough attention to the economic and employment effects of those being displaced from the city. Unfortunately, low income residents being forced to leave the city due to rising prices are losing more than just community- they are losing access to dense, urban neighborhoods that are uniquely suited to provide them with the services they need.

Gentrification will continue to be a loaded, tense word for years to come. Rents will still be much too high for too many people. But as we continue to disagree over and to debate the merits of plans for affordable housing, we cannot lose sight of the fact that more than just community character is at stake. If we are unable to accommodate our lower income neighbors, we will be forcing them to move to areas systemically unable to provide for their needs anywhere near as effectively as the cities they currently live in.