…within a span of a single day; everyday. Dense cities historically began growing outwards beyond its traditional limits; partly due to changing impacts of technology on transportation and partly due to changing nature of economies from manufacturing to services. Extensive transportation networks taking commuters in and out of the city gained popularity in almost all metropolitan cities of the world; both in the developed as well as the developing world. Initially, as for any radical idea, it was hailed as a solution to manage and plan cities better but back in the earlier half of the twentieth century, no one had envisioned the problem of sprawl, gridlocked roads, and sardine-like packed commuter trains.
According to a column on Governing.com [no permalink available, posted on October 27, 2005], expansion and contraction of cities has reached ridiculous proportions. “Vernon, Calif., near Los Angeles. At night, Vernon’s population is 91; in the day, it’s nearly 38,000.” This example might be an exaggeration but numbers for other cities are high too.
“Big cities that expand dramatically in the mornings: Washington, D.C. (72 percent larger at noon than midnight), Atlanta (62 percent larger), Tampa (48 percent) and Boston (41 percent). Detroit loses a few more people than it gains (659, to be exact, or about one-tenth of a percent), and San Jose, Calif., loses nearly 6 percent of its population.
The biggest cities, New York, Los Angeles and Chicago, had moderate gains in the daytime, 7 percent, 4 percent and 5 percent, respectively”
Washington, D.C. and Atlanta must seem like a large living organism that breathes in during the day and breathes out during the night. I have lived in Atlanta for almost 5 years and can vouch for the presence of hundreds of sub-divisions on the periphery or as they call it, the perimeter. These sub-divisions are in surrounding “residential” cities that almost empty out during the day. One look at the I-75/I-85 South (heading towards downtown) at 7am and you might think that an evacuation order is in effect. Two hour commutes are now part of the city’s life. At night the downtown wears a deserted look and is considered dangerous. If it wasn’t for the presence of a large state university (GSU), downtown Atlanta would resemble one of those forgotten city centers. Of course, downtown development is being pursued with enthusiasm and downtown condos are making a return slowly but surely. Strangely the three biggest cities of the nation do not expand and contract as much. Is it because the city’s culture has always reinforced downtown living? Or is it due to the presence of large sections of low-income neighborhoods that are simply stuck in the core city?
Are expanding and contracting cities considered good in planning circles? I am not entirely sure. Of course, public utilities might be more efficient and/or quicker in denser cities. If “non-flexing” cities are a good thing, then questions are raised on the kind of developments that keep the city’s size constant. Low-income neighborhoods might comprise a majority of those developments, making planners and authorities uncomfortable due to crime concerns. Incidentally, the two cities that expand and contract the most, Washington D.C. and Atlanta often lead other cities in the high crime list. So are dense cities less prone to crime, regardless of the demographics? Only a detailed comparative study will reveal more.