In the modern day, he world is experiencing an unprecedented amount of urbanization. The population of urban areas are regularly approaching over ten million people, and these are almost always in the developing world. Of the ten largest cities in the world according to the United Nations, four are on the Indian subcontinent and only Tokyo and New York are in the developing world. However, even in the United States this extreme urbanization is occurring but in a sense of urban sprawl. Slowly as population centers have spread out, a number of megaregions have formed across the country. And even now their shapes are evolving. Right now, there are eleven widely accepted megalopolises in the United States.
For a long time, the largest of these was the Boston-Washington corridor. Encompassing the metropolitan areas of New York City, Philadelphia, Baltimore, and Washington, D.C., its status as the largest urban agglomeration in the United States was obvious. However, that is beginning to change. The Midwest or Great Lakes megaregion is now eclipsing the Northeast Corridor in terms of population. With its center around Chicago, the megaregion has now grown to stretch across much of the Rust Belt to Cincinnati, Pittsburgh, and Detroit. But recently it has also begun spreading west. It is even beginning to spread far enough that Saint Louis and Minneapolis-Saint Paul could conceivably be considered part of the region. While the definitions of megaregions are certainly subjective, the definition outlined by the Regional Plan Association is the most widely accepted. Under this metric, the Great Lakes megaregion had a population of 54 million in 2000 compared to 49 million for the Northeast Corridor.
While these two are the largest in the country, their growth has largely stalled. As the population of the United States continues to shift south and west, it is there that you will find the fastest growing megaregions. The largest growing urban region in the country is the Texas Triangle, which covers the area between Austin-San Antonio, Dallas-Fort Worth, and Houston. This region is expected to grow by over 60 percent between 2000 and 2025. Meanwhile, the Florida region that covers most of the state has projected growth of almost half its current population, and the area around Phoenix is expected to grow by 30 percent. The Front Range corridor stretching from Cheyenne to Albuquerque is also expected to grow by half, but this could increase if the corridor begins extending further south toward El Paso. But the most important urban area in this area is definitely going to be California.
Right now, California is divided into two separate megaregions. The region around the Bay Area in the north has about 13 million people, while the southern megalopolis around Los Angeles and San Diego has 25 million people. But in the future, the growth and expansion of both regions into the outlying San Joaquin Valley could cause them to meet and merge. Right now, the Bay Area region extends out to Fresno and the Southern. California region goes north to Bakersfield. If the growth of these two regions goes at its current pace, they could join sometime in the next few decades.
with the prospect of this merge comes the challenge of how to manage this urban growth and the transportation and infrastructure issues that come with it. This is a similar issues that other megaregions around the country will likely face if future growth continues. While the highway system is a good one for going across the country, its use for shorter regional travel could become limited as environmental concerns escalate and as regional congestion becomes a larger issue. Air travel would also have limitations in the current climate due to long waits at airports making it unintuitive as well as the aforementioned environmental concerns. The clearest solution in these circumstances then would be a high speed rail network.
For California, a high speed rail connection from San Francisco to Los Angeles has been at the proposal stage since the 1980s, but is finally moving ahead. Initial plans are for the completion of the middle route from Fresno to Bakersfield by 2017 with the route extended to Merced and Palmdale by 2021. The extensions to the Bay Area and greater LA would come later with improved commuter rail access in the meantime. The overall plan for the system is good, but this implementation is poor. For a transportation system to be truly effective, it needs to be installed as a whole. The piecemeal addition of it, especially starting with what is likely to be one of the least used sections, shows a poor vision for the project. If it can survive to its final completion in 2028, however, it should be a significant boost to the state. Estimates are that the train will have half the travel times by car in the area. Even more impressive, the estimate for a San Francisco to Los Angeles route is two and a half hours, comparable to current air travel between the two cities.
This plan for high speed rail in megaregions could and should be extended to other parts of the United States, as it works especially well with regions that are already long corridors. In this respect, an extension and upgrade of the Acela trains to a full high speed rail would be a great boon to the Northeast. The issue here is that most rail in the United States prioritizes freight traffic, so either new exclusive track would need to be built or some deal would have to be made to make it effective.
ideally, the route could run from Boston to Washington passing through major cities in the New York, Philadelphia, and Baltimore metropolitan areas. Later, it could be extended south to connect with the megaregion in the interior South, passing through Richmond, Raleigh-Durham, Charlotte, Atlanta, and ending at Birmingham. A similar rail line could work for the Front Range corridor, roughly following I-25 from Cheyenne to El Paso. The Texas Triangle is more difficult to create a rail line for, but a loop around the region might be feasible.
This is of course only speculation on how the transportation networks of the United States will develop over the next half century, but with the creation of numerous large urban regions it may become the most efficient way to coordinate intercity travel in the US. With the development of urban megaregions recently, large connected networks like this to support travel between more regional hubs is going to become more necessary. Instead of continuing the American love affair with the automobile that worked in the 1960s, the United States needs to adapt to this new urban fabric and learn from the Europeans and the Japanese in this regard. Those areas have already had large urban agglomerations and have transportation networks to accommodate them, but the United States is only just now starting to encounter this problem. If we deal with this now, it won’t become more of a problem later, but we need to embrace the infrastructure overhaul in full if it is going to have a great effect.