The Mega-City Maker

Interstates created mega regions, and mega regions will change how we see this country and its transportation needs.
August 2005
Alex Marshall
By Alex Marshall  |  Columnist
Senior Fellow at The Regional Plan Association in New York City

When President Dwight D. Eisenhower signed legislation in 1956 to create the Interstate highway system, he probably thought he was making it easier for Americans to travel between existing towns and cities. What the general may not have realized was that he was also setting the nation on a course to create new cities, organized around those very same limited-access highways that now crisscross the country.

That indeed is what has happened. Almost a half-century later, new "mega cities," or "megalopolises" (the terms vary), have grown up around key Interstates, turning existing cities and towns into huge regional organisms.

Robert Lang, director of the Metropolitan Institute at Virginia Tech in Alexandria, writes about these new mega cities with his colleague Dawn Dhavale in "Beyond Megalopolis: Exploring

America's New 'Megapolitan' Geography." Lang and Dhavale identify 10 megalopolises--"clustered networks" of existing metropolitan areas that function in some ways as giant cities. The most dense and defined mega region, for instance, is the Northeast, stretching from Boston to Richmond. One is emerging around Phoenix and Tucson while another includes Chicago, Detroit, Pittsburgh and Minneapolis.

Many features define and create a mega region. The flow of goods, services and people--where the branch offices of a company are, where associated businesses and industries locate or emerge--play an important part. But the principal piece of infrastructure is the Interstate. One megalopolis, which stretches from Kansas City down through Oklahoma City, Dallas, Austin and San Antonio, is knit together by I-35. I-85 and I-81 pull together the Charlotte, Atlanta and Raleigh megalopolis.

"The Interstates were not planned to take on this role," Lang says. "The in-between spaces were thought of as just in-between spaces. At that time, the distances between say Seattle and Portland seemed very daunting, and the cities as very discreet." The idea that development could occur all along I-5, which links the Pacific Northwest cities, was simply not thought of.

Interstates create places differently than their 19th-century counterpart--railroads--did. Interstates have exits every few miles, which means in the long run you will get houses, offices and shopping centers every few miles. Over time, these rivers of concrete take on personalities. There are songs written about driving along I-95, which has more than 64 million people living within 50 miles of it. In a recent talk in New York, Lang noted that people in Oklahoma and Texas talk of I-35 as a "family freeway" because they visit relatives and friends along it so often.

Recognizing mega regions will change how we see this country. People think of the United States as low density. Yet almost 200 million people live in these 10 mega regions on less than 20 percent of the total land area. The densities of these megalopolises are substantially higher than France and Germany. Over the next 50 years, most of the 100 million or so new Americans expected to be here will probably choose to live and work in these megalopolises.

Suddenly, things like higher-speed train lines in these mega regions don't seem so far fetched. Better train service could be linked to airports, which would multiply the power of these two types of transportation. Or how about specialized "truckways," which would be a high-tech highway just for commercial goods through a mega region. Southern California, whose leaders already recognize their place in a megalopolis, is planning one to cement its role as logistics hub of the country. Over time, such new infrastructure could reshape the megalopolises in ways that reinforce the positives, such as good- paying jobs, and diminish the negatives, such as being stuck in traffic.

The Regional Plan Association in New York City is exploring just such options in a new campaign it is organizing: "America 2050: A National Strategy for Global Competitiveness." (Full disclosure: I am a Senior Fellow at RPA, where I have had a courtside seat to much of this work.) Lang based his megalopolis study in part on previous work done by the RPA and its frequent partner, the Lincoln Institute of Land Policy in Cambridge. RPA's president Robert Yaro is attempting to form a consensus for large scale "spatial planning" within and for these mega regions.

"These are our new competitive units in the global economy," Yaro says. "We've used up the capacity in our existing infrastructure systems, and we need to build more in a focused, thought-out way. Our competitors in Europe and Japan are doing this already."

All this may sound overly ambitious or unlikely, but it fits right in with the American tradition. After all, we created the Interstates.

Alex Marshall
Alex Marshall | Columnist |