So it appears there may be some academic heft behind some of the prognosticating I've been doing.

I came across a piece at Better Cities and Towns that suggests that America is at the onset of the Fifth Migration, according to Dr. Arthur C. Nelson, professor of city and metropolitan planning at the University of Utah and director of its Metropolitan Research Center. In the recently released issue of Planning Theory and Practice, Dr. Nelson says that trends that we're all aware of -- rising energy costs, stagnant incomes, growing wealth inequality, tighter home financing and shifting housing and community preferences -- are combining to make the next fifty years of American development look very different from the previous fifty. In fact, Dr. Nelson says the Fifth Migration, or Fifth Wave, could also be called America's Suburban Resettlement Movement. Driven by empty nester Baby Boomers and young professional Millennials, Dr. Nelson says development focus through the middle of this century will be on central city neighborhoods and mature, inner-ring suburbs, as they become "re-urbanized".

To which I say, I agree.



I made my point on this with my "Big Theory" series over the last several months. Earlier this month I wrote that the 2008 financial crisis likely put the nail in the coffin for the suburban pattern of the post-war era, and kicked off the next wave:

What I believe will happen is that perceived differences between “city” and “suburb” will begin to disappear. Suburbs will introduce more housing types than conventional single-family homes, to attract a more diverse group of residents. Edge cities will become more walkable. Downtowns and town centers will emerge where currently none exist. They’ll have to respond to the aging of their residents and the needs they have. Similarly, cities will continue to attract young, educated and affluent residents who will be attracted to the inherent adaptability of cities – their transit networks, mix of housing types, job centers, and amenities.

On the surface, in many places it will appear as the “city” is gaining as the “suburbs” are losing. However, the truth will be that there will be greater economic and social balance between the two, and that both will begin to look more similar than dissimilar. To me, this is a positive. I see this as a trend that will accelerate after 2020.

In fact, I can think of a new term to describe what will happen with metros that more accurately describes what I expect to happen -- The Great Congealing. After the hot, fast-paced expansion of the suburbs since World War II, the next phase of American development will cool down and thicken.

There will be some winners and losers at the community level, and it won't be a simple city-wins-and-suburbs-lose game. I think access will drive this shift, and, to a lesser extent, each community's quantity of small-to-medium size households on small-to-medium sized lots. So yes, to the extent that some exurbs went all out on large-lot single family development, and chooses to stay there, they may end up on the wrong side of the emerging trends. But there will likely be plenty of opportunities for communities to alter their course.

At the outset, however, some communities may be aligned for future success. Let's look at the map below to see how some communities in the Chicago region may be ready (or not ready) for the Great Congealing:

This map shows the municipal boundaries for the 284 suburbs in the seven-county Chicago metropolitan area, as well as the 77 defined community areas within the City of Chicago (outlined in bold). The colors detail community areas and suburbs by transportation access -- the green areas are served by both rail transit and interstates; the darker yellow areas are served by rail transit only; the lighter yellow areas are serve by interstates only; and those left blank are served by neither.

If you're wondering how the Great Congealing might play out in the Chicago area, areas that have the best current access, either both rail and highway or one or the other, might be at the leading edge of the trend. Coincidentally, the areas that have the greatest access are generally the ones that have the most eclectic mix of small, medium and larger home lots, possibly making them more attractive to a wider range of potential home buyers and renters than others.

I expect that this pattern will play out in metros around the country, even in those currently without rail access. Older areas with a more diverse mix of land uses will benefit; the more homogeneous places may have to adapt quickly or risk decline.



How will we know for sure that the Great Congealing is occurring? We'll have to wait for the economy to end its slow trot toward recovery and pick up the pace. If residential and commercial builders are betting on mature communities with better transportation access, the shift is on.