Repost: Todd Litman and the Access Revolution

Mobility is less important than access

Todd Litman, a transportation analyst for the Victoria Transportation Planning Institute, proposes a paradigm shift for transportation. Instead of defining and measuring transportation in terms of mobility, his normative theory supports basing transportation in terms of access. In practical terms, the difference is between evaluating transportation in terms of mobility (traffic volume, average speeds, top speeds, and distance traveled) and access (how many useful activities can be facilitated). Some people can buy their groceries next door, from down a flight of stairs, or from several floors traveled by elevator. Others obtain groceries only after driving for miles. In the old paradigm, the longer grocery trip is given favorable treatment compared to the shorter trip. The access-based transportation analysis judges that all trips for groceries are equally important. With access-based thinking, sustainable solutions are easier to imagine.

Google Street View of Rue St Jacques in Paris. It is possible to live, work, and shop all in this neighborhood.

In mobility-based thinking, traveling is an end. In access-based transportation, travel is merely a means. So the old-school traffic engineers measure traffic volumes and level-of-service (LOS). What if a business evaluated the productivity of their workers on the basis of whether they maximized the number of steps they took on the shop floor? Any production process attempts to minimize motion. Industrial engineers attempt to produce a single widget with human labor that minimizes the number of steps and other movements. Transportation engineers, on the other hand, think that more motion and more distance traveled is good. By contrast, access-based analysis is more concerned with human activities being fulfilled. If groceries can be procured from next door or the backyard garden, it is just getting groceries. Getting groceries from far away does not make the grocery-trip better. In terms of access-based thinking, locating close to goods and services facilitates important human activities just as well as does moving people at high speeds over long distances. Therefore, the access paradigm takes us to sustainable solutions more readily than does the mobility paradigm.