Transport Planning

Once again the Texas Transportation Institute (TTI) published its annual Urban Mobility Report (UMR), and once again I feel obliged to warn planners that it is based on faulty assumptions and biased analysis methods. This is not to deny that traffic congestion is a significant problem, but the UMR significantly exaggerates its importance compared with other transport costs and exaggerates roadway expansion benefits.

A few weeks ago the Texas Transportation Institute (TTI) released its latest Urban Mobility Report, and yesterday INRIX released its National Traffic Scorecard 2010 Annual Report. Both paint a grim picture of roadway conditions.

“America is back on the road to gridlock,” warns INRIX.

Why didn’t the chicken cross the road?

Because pedestrian Level-Of-Service was below “C”.

The graph below shows the most recent USDOT vehicle-travel data covering the last 25 years. Although vehicle-miles of travel (VMT) grew steadily during most of the Twentieth Century, in recent years the growth rate stopped and even declined a little. It is now about 10% below where it would have been had past trends continued.

Time is a limited and valuable resource. As much as possible, people should spend the precious hours of their lives in the most satisfying and productive possible ways. This has important implications for transportation planning, since most people spend a significant amount of time in transport, and travel time savings are often the greatest projected benefits of transport projects such as roadway and transit service improvements.

I spent the last week teaching a professional development course for young planners in Buenos Aries, Argentina. It’s been a wonderful experience – my students are smart and enthusiastic, and Buenos Aries is a vibrant city with old-world charm. The buildings, plazas and old statues are beautiful and dignified, although a little frayed around the edges.

Should society encourage parents to drive children to school rather than walk or bicycle? Should our transportation policies favor driving over walking, cycling, ridesharing, public transit and telecommuting? Probably not. There is no logical reason to favor automobile travel over other forms of accessibility, and there are lots of good reasons to favor efficient modes, so for example, schools spend at least as much to accommodate a walking or cycling trip as an automobile trip, and transportation agencies and employers spend at least as much to improve ridesharing and public transit commuting as automobile commuting.

Politicians and planners be warned: you will now be judged according to your ability to improve walking, cycling and public transit services.