If the New Urbanism can be boiled down to a single idea, perhaps it would be making places walkable. But what makes pedestrians feel attracted to one place and want to avoid another?
One answer is simple proximity. A place that is within a quarter mile of shops, houses, schools, parks, entertainment venues, workplaces, and other types of uses has the potential to be highly walkable. This proximity is measured by the Walkscore website.
But there is much more to walkability than proximity. The quality of the walk is just as important, perhaps more so, than the distance. In other words, walkability is more about the journey than the destinatation. The way walking routes are laid out has a huge impact on that journey.
For example, the pattern of blocks and streets is critical. Most highly walkable places are organized into a fine-grained pattern of streets and blocks. See for example, the Google map view of a neighborhood in San Francisco. The blocks are approximately 480 feet by 240 feet — under 4 acres each. This pattern provides about 230 intersections per square mile. Although the numbers may sound technical to a lot of people, they indicate a fine-grained block pattern that allows for a lot of diversity that is interesting to pedestrians. The intersections are attractive to commercial uses, and the large number of blocks can have their own individual character. Walkers can choose for an almost infinite number of potential routes to get through the neighborhood. Perhaps more importantly, automobile traffic is dispersed — which allows streets to be built at a human scale that is not intimidating or dangerous for pedestrians.
On the other hand, the suburban area in Virginia Beach has a very large-grain block pattern. According to the Center for Neighborhood Technology, the average block size in this census tract is 12-16 acres. A pedestrian trying to get from one place to another finds the distances interminable and the lack of variety unappealing. Automobile traffic is concentrated on commercial streets that must be built very large. Pedestrians immediately sense the danger and get in a car if at all possible.
Beyond the block and street pattern, the design of the thoroughfares is also critical. Are they too wide, allowing traffic to move dangerously fast? Are crossing distances so great that pedestrians feel vulnerable getting from one block to the next? In downtown Los Angeles — a place with a very high Walkscore due to the proximity of uses — I found that a pedestrian has to be in good physical condition just to get across the street. The thoroughfares are so wide that often pedestrians have to trot or run to the curb to ensure that they are not caught in the middle when traffic begins to move again. That’s not very walkable. The most walkable places, in general, are those with narrow thoroughfares that are easy to traverse.
Details such as sidewalk width, street trees, on-street parking, and architecture are also critical to walkability. It is difficult to describe the complete ensemble that makes a place walkable. Each walkable place is unique. Dan Burden — one of the foremost experts on the details of walkable places — describes three characteristics of a place that make it walkable. One is transparency — being able to see adjacent environments such as the inside of shops, or across the street into a park — is important. A sense of enclosure — the coziness that is produced by the space between buildings and street trees — also serves to make pedestrians more comfortable. Another critical quality is human scale — a higher quality pedestrian environment is created with a lot of small-scale buildings rather than a single large building.