Tuesday, September 23, 2014

The kind of problem a city is

This new piece by the Atlantic's CityLab.com writer Michael Mehaffy looks at the newest thinking about cities, and concludes, in essence, that Jane Jacobs was right. (see“5 Key Themes Emerging From the 'New Science of Cities.”)

Mehaffy writes: "In the past few years, a remarkable body of scientific research has begun to shed new light on the dynamic behavior of cities, carrying important implications for city-makers. Researchers at cutting-edge hubs of urban theory like the University College London and the Santa Fe Institute have been homing in on some key properties of urban systems—and contradicting much of today's orthodoxy."

The researchers, Mehaffy says, are finding that they're essentially proving the value of much of what urban writer Jane Jacobs (not a planner, not an architect, not an academician) explored in the 1950s 
through the 1990s:
 
"Jacobs was also famous for excoriating the backward-looking “pseudo-science” of that era's planning and architecture, which she said seemed “almost neurotic in its determination to imitate empiric failure and ignore empiric success.”  She urged city-makers to understand the real “kind of problem a city is”—not a conventional problem of top-down mechanical or visual order, but a complex problem of interacting factors that are “interrelated into an organic whole.”

He quotes physicist Geoffrey West of the Santa Fe Institute saying they are just doing “Jacobs with the math.”

The five key themes?

1.Cities generate economic growth through networks of proximity, casual encounters and “economic spillovers." The creativity and prosperity of cities like New York, Mehaffy writes, is “ a dynamic interaction between web-like networks of individuals who exchange knowledge and information about creative ideas and opportunities.” Many of those interactions are casual, taking place in “networks of public and semi-public spaces—the urban web of sidewalks, plazas, and cafes. More formal and electronic connections supplement, but do not replace, this primary network of spatial exchange.” 

2. Through a similar dynamic, cities generate a remarkably large "green dividend.

3. Cities perform best economically and environmentally when they feature pervasive human-scale connectivity. "...to the extent that the city's urban fabric is fragmented, car-dependent or otherwise restrictive of casual encounters and spillovers, that city will under-perform—or require an unsustainable injection of resources to compensate." (Sound like any place you know?) 

4. Cities perform best when they adapt to human psychological dynamics and patterns of activity.

5. Cities perform best when they offer some control of spatial structure to residents. 

These theories seem to point to future difficulties for auto-oriented, disconnected Sun Belt-form cities such as Charlotte, Raleigh, Atlanta, etc.—places that today are growing like gangbusters. Can those cities recover the old networks of connectivity they had when they were small, pedestrian and streetcar-oriented towns of the 19th and early 20th centuries?