8 Myths of Traffic Planning

In their masterful book Traffic Calming, residents fighting a destructive road project in Brisbane, Australia expose the myths that underlie most traffic plans. Traffic engineers in New York City rely on these myths to justify  widening highways or expanding road capacity to favor cars over pedestrians.

Planners also use these myths to reject full-size bike lanes on dangerous arterial streets or to deny traffic calming projects. These myths always favor automobile traffic over walkers and cyclists.

Myth 1: Traffic projections are important in deciding what roads are needed.
Most transportation studies forecast future traffic by projecting current trends; then planners use the projections to determine what roads are needed for the future. This approach seems rational until one realizes that it assumes that the present car-choked situation is ideal and that present travel habits are worth projecting into the future.

Myth 2: Planners are not responsible for how much people want to use their cars.
Present travel habits were not formed in a vacuum, nor were they inevitable. They are the results of choices and policy decisions by past and present governments and agencies. Other cities have developed in entirely different ways.

The volume of traffic is not something like rainfall that has to be accepted. No unseen force decrees that Houston residents will consume eight times as much gasoline per person as do New Yorkers.

Myth 3: Predicted traffic growth must be provided for.
Traditional planners claim that it is irresponsible not to build bigger roads to cater to predicted traffic growth. But it is almost universally acknowledged that new or upgraded roads create new traffic, as new trip destinations are made possible. Then the frequency of trips increases, people accept jobs farther from their homes, and travel shifts from mass transit to cars.

Ironically, most communities try to overcome traffic problems in ways that actually perpetuate them. Traffic studies base traffic predictions on past trends and travel habits, which were created by past road expansions. But the new traffic created by the new road capacity fills the road within a couple of years, causing the traffic planner to congratulate himself on his foresight, Finally, another study predicts more traffic, and the need for further expansion, and the cycle begins again.

This type of planning causes more traffic, and cannot keep pace with growth. Even so-called "minor" upgrades increase traffic, leading to major upgrades tomorrow and enormous ones later.

Myth 4: Bigger roads are safer.
Those who claim that bigger roads are safer tend to cite statistics showing a lower number of fatalities per mile traveled. Such statistics are misleading for a few reasons.

First, larger roads might not be the cause of such a drop. In fact, the major causes of the drop in fatalities per mile traveled may have been advances in protective technology like seat belts and air bags, as well as 'in emergency first aid and medicine.

Second, because the new or upgraded roads encourage more or longer trips, the number killed has risen when compared to the number of cars or the number of trips. In addition, wider, straighter roads encourage speed, so pedestrians are more likely to die when hit. Fourth, increasing the safety of a road encourages drivers to take greater risks. The best solution to the problems of car speed is the institution of measures meant to force drivers to travel at lower speeds.

Myth 5: Big roads increase mobility.
This myth, perhaps the most widely accepted of the eight, seems irrefutable until one considers the difference between the distance and the quality of the destination. Because roads encourage a city and metropolitan area to spread out, everyone must travel farther to get to work, the store, or a friend's house.

Instead of a five-minute walk to the local store, it's a twenty-minute drive to the distant megastore. As fewer people ride transit and transit becomes less viable, roads become more clogged and drivers spend more time in their cars sitting in traffic. In the end, everyone spends more time getting to fewer destinations.

Myth 6: Bigger roads help more people than they hurt.
Most planners believe that more and larger roads benefit most members of society. But money spent on roads helps but a minority of residents, especially in New York City, where only 44% of households have access to a car.

An over-emphasis on roads harms children, who are more likely to be hit by motor vehicles and who must restrict their play to make way for more cars. Community residents suffer when heavy traffic and its noise tear at the social fabric of a neighborhood.

One study showed that residents of low-traffic streets had many more friends and acquaintances on their streets than did those who lived on high-traffic streets. Small businesses lose customers as pedestrians avoid unpleasant areas, and the city as a whole loses historic buildings and parks that must give way to increasing space for cars.

Myth 7: It is not the job of traffic planners to look at wider social, political and environmental needs.
Most traffic plans do not take into consideration the larger needs of the community in which the plans are carried out. Despite laws that call for environmental impact reviews, most highway plans look narrowly at one objective: moving more cars faster.

If, however, goals such as the reduction of noise, pollution, and traffic and the enhancement of safety are substituted for such a limited vision, then it becomes clear that the only way to achieve such goals is to reduce, not increase, the number of cars on highways and streets.

Myth 8: Planning should be left to the experts.
Too often, traffic planners simply decide how much traffic will increase, then build the roads to accommodate it. In fact, such "planners" should not be called planners, but rather "facilitators" or "road builders." The local community must have the final say in building roads, for local residents will bear the consequences of new and larger roads.

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