Flow is what defined Moses' transportation projects for New York and its suburbs. Traffic should flow along wide freeways to wide bridges and tunnels. This flow defines most American cities today.
Moses hit his final roadblock in the form of Jane Jacobs. Her 1961classic The Death and Life of American Cities marked the start of the New Urbanism. It rejected flow in favor of a livable destination.
Cars and people have been at war ever since. Ground zero today is in my home town of Atlanta.
Decatur Street runs from the center of the city, called Five Points, to (surprise) the town of Decatur, 6 miles east. For years I used it to take my kids to elementary school. (Above is what the street looked like two years, ago, from a WSB story about a student being hit by a truck.)
Now the youngest is heading for college. On Decatur Street. Specifically he will be going to Georgia State University, which has launched a major "traffic calming project."
The idea was to turn a four-lane road into two lanes, with wider sidewalks. It's a nightmare for the 15,000 cars a day that travel Decatur Street to the CNN Center, but for students and teachers -- especially those who use the MARTA mass transit service -- it's a godsend.
(The image is from Georgia State University. It's not how the finished project looks. The center island trees were taken out because cars kept running into them.)
No more risking life and limb getting between classes because someone in a car wants to get to their dentist five minutes faster. They're stuck. You go.
The IBM solution includes congestion tolls, used to reduce traffic in Stockholm, roadside sensors used to predict backups in Singapore and simulations meant to guide traffic planning in Kyoto.
They all make sense. But there is another, more basic choice that has to be made. Namely, how are we going to get around, and which method of getting around is the city meant to serve?
The Atlanta region is Moses. It's about flow, about freeways. Most solutions being offered emphasize flexible tolls that will let the rich zoom past the poor on those freeways.
Atlanta's center is becoming Jacobs. It's about being here, on foot or on a bicycle. It's about the destination, not the journey.
The smartest city will find ways to support both. People and goods have to get around. But they also need destinations. Getting off the freeway and into the crowd is the challenge.