Concerns about an Urban Mobility Study

By Dom Nozzi

I just read an “urban mobility study.” I have a few important concerns.

The underlying assumptions in the study seem to be highly flawed, or otherwise questionable. For example, I do not buy the conventional wisdom expressed in the study that congestion results in increased travel time and increased fuel consumption. Newman and Kenworthy are a must read on this issue, arguing persuasively that the reverse is true.

I am a huge supporter of planned congestion for several reasons. Fighting against congestion is part of the road-building, home-building and auto-maker lobby paradigm, because they know that if we try to fight congestion, we will get more road widenings, more cars, more car travel and more sprawl.

One reason I like congestion is that, as Ian Lockwood from West Palm Beach says, congestion creates a “time tax” for motorists. That is, the motorist pays a “fee” when they are slowed down due to lost time (they are “paying” with their time). And in our political climate, it is nearly impossible to have motorists pay the real cost of their travel through high gas taxes or congestion fees.

Instead, we keep motorists on welfare.

The best we can do, therefore, is to indirectly charge the motorist with a time tax by passively avoiding the use of conventional ways to reduce congestion (such as widening a road or intersection). Another huge benefit to congestion is that it is, by far, the most effective way for us to slow or reverse sprawl. Researchers have learned that cross-culturally and throughout history, humans, on average, will live in a place that creates a round-trip commute time of approximately 1.1 hours per day. Therefore, when we widen roads, the faster commute time that is briefly created will enable more dispersed residential sprawl to get us back to the 1.1 hour equilibrium. These impacts are inevitable, regardless of how wonderful your land use plan is. Conversely, then, the time tax created by congestion contracts our residential patterns as people seek to maintain that 1.1 hour equilibrium.

Another highly flawed assumption in the study is that road widenings are one of the tools that can have a long-term beneficial impact on delays caused by congestion. In fact, in an already congested urban area, the triple convergence theory by Downs shows, convincingly, that this will not only be a huge waste of public dollars in terms of reducing delay, but will actually make nearly everything worse.

The study does admit that there has been a very disturbing (to the conventional thinkers) upward trend over the past decade or so in the number of roads in the U.S. that are now highly congested. I am amused that the authors do not draw a connection between this, and the fact that this country has spent trillions over the past several decades to fight congestion — and has failed catastrophically. It is perhaps the most misguided and damaging action taken in human history, yet the authors do not mention that the huge congestion increases occurred concurrently with the widening efforts. They also ignore the recent studies regarding induced traffic, in which it is shown that widenings actually create car trips that would not have occurred without the widening — thereby validating The Triple Convergence and Newman/Kenworthy.

As Kulash says, fighting congestion by widening is like loosening your belt to fight obesity. Or, it is like throwing fuel on a fire in an effort to put out the fire.

Only later, and in passing, do the authors indicate we will need lifestyle and land use changes to help us.

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Filed under Sprawl, Suburbia, Transportation

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