WHY TRAFFIC IS CONGESTED
The first complaint one always hears about suburbia is the traffic congestion. More than any other factor, the perception of excessive traffic is what causes citizens to take up arms against growth in suburban communities. This perception is generally justified: in most American cities, the worst traffic is to be found not downtown but in the surrounding suburbs, where an "edge city" chokes highways that were originally built for lighter loads. In newer cities such as Phoenix and Atlanta, where there is not much of a downtown to speak of, traffic congestion is consistently cited as the single most frustrating aspect of daily life.
Why have suburban areas, with their height limits and low density of population, proved to be such a traffic nightmare? The first reason, and the obvious one, is that everyone is forced to drive. In modern suburbia, where pedestrians, bicycles, and public transportation are rarely an option, the average household currently generates thirteen car trips per day. Even if each trip is fairly short—and few are — that's a lot of time spent on the road, contributing to congestion, especially when compared to life in traditional neighborhoods. Traffic engineer Rick Cheliman, in his landmark study of Portsmouth, New Hampshire, applied standard suburban trip-generation rates to that town's historic core, and found that they predicted twice as much traffic as actually existed there. Owing to its pedestrian-friendly plan—and in spite of its pedestrian-unfriendly weather—Portsmouth generates half the automobile trips of a modern-day suburb.
But even if the suburbs were to generate no more trips than the city, they would still suffer from traffic to a much greater extent because of the way they are organized. The diagram shown here illustrates how a suburban road system, what engineers call a sparse hierarchy, differs from a traditional street network. The components of the suburban model are easy to spot in the top half of the diagram: the shopping mall in its sea of parking, the fast-food joints, the apartment complex, the looping cul-de-sacs of the housing subdivision. Buffered from the others, each of these components has its own individual connection to a larger external road called the collector. Every single trip from one component to another, no matter how short, must enter the collector. Thus, the traffic of an entire community may rely on a single road, which, as a result, is generally congested during much of the day. If there is a major accident on the collector, the entire system is rendered useless until it is cleared.
A typical neighborhood is shown in the bottom half of the diagram. lt accommodates all the same components as the suburban model, but they are organized as a web, a densely interconnected system that reduces demand on the collector road. Unlike suburbia, the neighborhood presents the opportunity to walk or bicycle. But even if few do so, its gridded network is superior at handling automobile traffic, providing multiple routes between destinations. Because the entire System is available for local travel, trips are dispersed, and traffic on most streets remains light. If there is an accident, drivers simply choose an alternate path. The efficiency of the traditional grid explains why Charleston, South Carolina, at 2,500 acres, handles an annual tourist load of 5.5 million people with little congestion, while Hilton Head Island, ten times larger, experiences severe backups at 1.5 million visitors. Hilton Head, for years the suburban planners' exemplar, focuses all its traffic on a single collector road.
The suburban model does offer one advantage over the neighborhood model: it is much easier to analyze statistically. Because every single trip follows a predetermined path, traffic can be measured and predicted accurately. When the same measurement techniques are applied to an open network, the statistical chart goes flat; prediction becomes impossible and, indeed, unnecessary. But the suburban model still holds sway, and traffic engineers enjoy a position of unprecedented infiuence, often determining single-handedly what gets built and what doesn't. That traffic can occupy such a dominant position in the public discourse is indication enough that planning needs to be rethought from top to bottom.
WHEN NEARBY IS STILL FAR AWAY
Another paradox of suburban planning is the distinction that it creates between adjacency and accessibility. While many of the destinations of daily life are often next to each other, only rarely are they easy to reach directly.
For example, even though the houses pictured here are adjacent to the shopping center, in experience they are considerably more distant. Local ordinances have forced the developers to build a wall between the two properties, discouraging even the most intrepid citizen from walking to the store. The resident of a house just fifty yards away must still get into the car, drive half a mile to exit the subdivision, drive another half mile on the collector road back to the shopping center, and then walk from car to store. What could have been a pleasant two-minute walk down a residential street becomes instead an expedition requiring the use of gasoline, roadway capacity, and space for parking.
Supporters of this separatist single-use zoning argue that people do not want to live near shopping. This is only partially true. Some don't, and some do. But suburbia does not provide that choice, because even adjacent uses are contrived to be distant. The planning model that does provide citizens with a choice can be seen in the New England town pictured here. One can live above the store, next to the store, five minutes from the store, or nowhere near the store, and it is easy to imagine the different age groups and personalities that would prefer each alternative. In this way and others, the traditional neighborhood provides for an array of lifestyles. In suburbia, there is only one available lifestyle: to own a car and to need it for everything.
THE AMERICAN TRANSPORTATION MESS
THE HIGHWAYLESS TOWN AND THE TOWNLESS HIGHWAY;
WHY ADDING LANES MAKES TRAFFIC WORSE;
THE AUTOMOBILE SUBSIDY
During the height of automania, a zoologist observed that in animal herds excessive mobility was a sure sign of distress and asked whether this might not be true of his fellow human beings. Perhaps it was distress but what historian can list all the causes that led twentieth century man to race from highway to byway, tunnel to bridge? Suffice to say that he seemed to be constantly going from where he didn't want to be to where he didn't want to stay.
- PERCIVAL GOODMAN, COMMUNITAS (1960)
Redesigning streets and roads for pedestrian viability is a first step toward making our neighborhoods more livable, but there is a larger problem still to be addressed: this country's fundamentally misguided approach to transportation planning as a whole. Because settlement patterns depend more than anything else upon transportation Systems, it is impossible to discuss one without discussing the other.
While we do enjoy the benefits of an effective system for the national distribution of goods—nobody is lining up outside shops with empty shelves—it would still be difficult to overstate the degree to which transportation policy has damaged both our cities and our countryside. This outcome was by no means inevitable; in fact, we knew better all along. By 1940, the rules that should govern the development of a transportation network for the healthy growth of society were well known. They were widely acknowledged, thoroughly disseminated, and, apparently immediately forgotten.
THE HIGHWAYLESS TOWN
AND THE TOWNLESS HIGHWAY
The most significant of these rules is illustrated, alongside its violation, in the accompanying diagram. This drawing, more than any other, depicts the greatest failure of American postwar planning, and helps to explain why our country faces both an urban and an environmental crisis. Titled "The Townless Highway and the Highwayless Town," the upper half illustrates the proper relationship between high-speed roadways and places of settlement. Highways connect cities hut do not pass through them. Norman Bel Geddes, the designer of the U.S. Interstate system, declared in 1939, "Motorways must not be allowed to infringe upon the City." Where they do provide access to the City, highways must take on the low-speed geometries of avenues and boulevards. In exchange for this courtesy, the city does not allow itself to grow along the highway. Where high-speed roads pass through the countryside, roadside development is not permitted. The results of these rules are plain to see in much of Western Europe: cities, for the most part, have retained their pedestrian-friendly quality, and most highways provide views of uninterrupted countryside.
This country has allowed the exact opposite to occur. As depicted in the lower half, highways were routed directly through the centers of our Cities, eviscerating entire neighborhoods—typically, African American neighborhoods—and splitting downtowns into pieces. Meanwhile, the commercial strip attached itseif like a parasite to the highway between cities, impeding through traffic and blighting the countryside in the process. The damage is not yet complete, for we continue to let this happen, with predictable results. How obvious and damaging does an error need to be before it is addressed and corrected? Jane Jacobs may have answered this question in The Death and Life of Great American Cities: "The pseudo-science of planning seems almost neurotic in its determination to imitate empiric failure and ignore empiric success."
WHY ADDING LANES MAKES TRAFFIC WORSE
There is, however; a much deeper problem than the way highways are placed and managed. It raises the question of why we are still building highways at all. The simple truth is that building more highways and widening existing roads, almost always motivated by concern over traffic, does nothing to reduce traffic. In the long run, in fact, it increases traffic. This revelation is so counterintuitive that it bears repeating: adding lanes makes traffic worse. This paradox was suspected as early as 1942 by Robert Moses, who noticed that the highways he had built around New York City in 1939 were somehow generating greater traffic problems than had existed previously. Since then, the phenomenon has been well documented, most notably in 1989, when the Southern California Association of Governments concluded that traffic-assistance measures, be they adding lanes, or even double-decking the roadways, would have no more than a cosmetic effect on Los Angeles traffic problems. The best it could offer was to tell people to work closer to home, which is precisely what highway building mitigates against.
Across the Atlantic, the British government reached a similar conclusion. Its studies showed that increased traffic capacity causes people to drive more — a lot more — such that half of any driving-time savings generated by new roadways are lost in the short run. In the long run, potentially all savings are expected to be lost. In the words of the Transport Minister, "The fact of the matter is that we cannot tackle our traffic problems by building more roads." While the British have responded to this discovery by drastically cutting their road-building budgets, no such thing can be said about Americans.
There is no shortage of hard data. A recent University of California at Berkeley study covering thirty California counties between 1973 and 1990 found that, for every 10 percent increase in roadway capacity, traffic increased 9 percent within four years' time. For anecdotal evidence, one need only look at commuting patterns in those cities with expensive new highway systems. USA Today published the following report on Atlanta: "For years, Atlanta tried to ward off traffic problems by building more miles of highways per capita than any other urban area except Kansas City... As a result of the area's sprawl, Atlantans now drive an average of 35 miles a day, more than residents of any other city." This phenomenon, which is now well known to those members of the transportation industry who wish to acknowledge it, has come to be called induced traffic.
The mechanism at work behind induced traffic is elegantly explained by an aphorism gaining popularity among traffic engineers: "Trying to cure traffic congestion by adding more capacity is like trying to cure obesity by loosening your belt." Increased traffic capacity makes longer commutes less burdensome, and as a result, people are willing to live farther and farther from their workplace. As increasing numbers of people make similar decisions, the long distance commute grows as crowded as the inner city, commuters clamor for additional lanes, and the cycle repeats itself. This problem is compounded by the hierarchical organization of the new roadways, which concentrates through traffic on as few streets as possible.
The phenomenon of induced traffic works in reverse as well. When New York's West Side Highway collapsed in 1973, an NYDOT study showed that 93 percent of the car trips lost did not reappear elsewhere; people simply stopped driving. A similar result accompanied the destruction of San Francisco's Embarcadero Freeway in the 1989 earthquake. Citizens voted to remove the freeway entirely despite the apocalyptic warnings of traffic engineers. Surprisingly, a recent British study found that downtown road removals tend to boost local economies, while new roads lead to higher urban unemployment. So much for road-building as a way to spur the economy.
If traffic is to he discussed responsibly, it must first be made clear that the level of traffic which drivers experience daily, and which they bemoan so vehemently, is only as high as they are willing to countenance. If it were not, they would adjust their behavior and move, carpool, take transit, or just stay at home, as some choose to do. How crowded a roadway is at any given moment represents a condition of equilibrium between people’s desire to drive and their reluctance to fight traffic. Because people are willing to suffer inordinately in traffic before seeking alternatives — other than clamoring for more highways — the state of equilibrium of all busy roads is to have stop and go traffic. The question is not how many lanes must he built to ease congestion but how many lanes of congestion you want. Do you favor four lanes of bumper-to-bumper traffic at rush hour, or sixteen?
This condition is best explained by what specialists call latent demand. Since the real constraint on driving is traffic, not cost, people are always ready to make more trips when the traffic goes away. The number of latent trips is huge—perhaps 30 percent of existing traffic. Because of latent demand, adding lanes is futile, since drivers are already poised to use them up.
While the befuddling fact of induced traffic is well understood by sophisticated traffic engineers, it might as well be a secret, so poorly has it been disseminated. The Computer models that transportation consultants use do not even consider it, and most local public works directors have never heard of it at all. As a result, from Maine to Hawaii, City, county, and even state engineering departments continue to build more roadways in anticipation of increased traffic, and, in so doing, create that traffic. The most irksome aspect of this situation is that these road-builders are never proved wrong; in fact, they are always proved right: "You see," they say, I told you that traffic was coming."
The ramifications are quite unsettling. Almost all of the billions of dollars spent on road-building over the past decades have accomplished only one thing, which is to increase the amount of time that we must spend in our cars each day. Americans now drive twice as many miles per year as they did just twenty years ago. Since 1969, the number of miles cars travel has grown at four times the population rate.' And we're just getting started: federal highway officials predict that over the next twenty years congestion will quadruple. Still, every congressman, it seems, wants a new highway to his credit.
Thankfully, alternatives to road-building are being offered, but they are equally misguided. If, as is now clear beyond any reasonable doubt, people maintain an equilibrium of just-bearable traffic, then the traffic engineers are wasting their time—and our money on a whole new set of stopgap measures that produce temporary results at best. These measures, which include HOV (high-occupancy vehicle) lanes, congestion pricing, timed traffic lights, and "smart streets," serve only to increase highway capacity, which causes more people to drive until the equilibrium condition of crowding returns. While certainly less wasteful than new construction, these measures also do nothing to address the real cause of traffic congestion, which is that people choose to put up with it.
We must admit that, in an ideal world, we would be able to build our way out of traffic congestion. The new construction of 50 percent more highways nationwide would most likely overcome all of the latent demand. However, to provide more than temporary relief, this huge investment would have to be undertaken hand in hand with a moratorium on suburban growth. Otherwise, the new subdivisions, shopping malls, and office parks made possible by the new roadways would eventually choke them as well. In the real world, such moratoriums are rarely possible, which is why road-building is typically a folly.
Those who are skeptical of the need for a fundamental reconsideration of transportation planning should take note of something we experienced a few years ago. In a large working session on the design of Playa Vista, an urban infill project in Los Angeles, the traffic engineer was presenting a report of current and projected congestion around the development. From our seat by the window, we had an unobstructed rush-hour view of a street he had diagnosed as highly congested and in need of widening. Why, then, was traffic flowing smoothly, with hardly any stacking at the traffic light? When we asked, the traffic engineer offered an answer that should be recorded permanently in the annals of the profession: "The computer model that we use does not necessarily bear any relationship to reality."
But the real question is why so many drivers choose to sit for hours in bumper-to-bumper traffic without seeking alternatives. Is it a manifestation of some deep-seated self-loathing, or are people just stupid? The answer is that people are actually quite smart, and their decision to submit themselves to the misery of suburban commuting is a sophisticated response to a set of circumstances that are as troubling as their result. Automobile use is the intelligent choice for most Americans because it is what economists refer to as a "free good": the consumer pays only a fraction of its true cost.
The authors Stanley Hart and Alvin Spivak have explained that: We learn in first-year economics what happens when products or services become "free" goods. The market functions chaotically; demand goes through the roof. In most American cities, parking spaces, roads and freeways are free goods. Local government services to the motorist and to the trucking industry — traffic engineering, traffic control, traffic lights, police and fire protection, street repair and maintenance—are all free goods.
THE AUTOMOBILE SUBSIDY
To what extent is automobile use a "free" good? According to Hart and Spivak, government subsidies for highways and parking alone amount to between 8 and 10 percent of our gross national product, the equivalent of a fuel tax of approximately $3.50 per gallon.
If this tax were to account for "soft' costs such as pollution cleanup and emergency medical treatment, it would be as high as $9.00 per gallon. The cost of these subsidies — approximately $5,000 per car per year — is passed directly on to the American citizen in the form of increased prices for products or, more often, as income, property, and sales taxes. This means that the hidden costs of driving are paid by everyone: not just drivers, but also those too old or too poor to drive a car. And these people suffer doubly, as the very transit systems they count on for mobility have gone out of business, unable to compete with the heavily subsidized highways.
Even more irksome is the fact that spending on transit creates twice as many new jobs as spending on highways. In fact, every billion dollars reallocated from road-building to transit creates seven thousand jobs. Congress's recent $41 billion highway bill, had it been allocated to transit, would have employed an additional quarter-million people nationwide.
Because they do not pay the full price of driving, most car owners choose to drive as much as possible. They are making the correct economic decision, but not in a free-market economy. As Hart and Spivak note, an appropriate analogy is Stalin's Gosplan, a Soviet agency that set arbitrary "correct" prices for many consumer goods, irrespective of their cost of production, with unsurprising results. In the American version of Gosplan, gasoline costs one quarter of what it did in 1929 (in real dollars). One need look no further for a reason why American cities continue to sprawl into the countryside. In Europe, where gasoline costs about four times the American price, long-distance automotive commuting is the exclusive privilege of the wealthy, and there is relatively little suburban sprawl.
The American Gosplan pertains to shipping as well. In the current structure of subsidization, trucking is heavily favored over rail transport, even though trucks consume fifteen limes the fuel for the equivalent job. The government pays a $300 billion subsidy to truckers unthinkingly, while carefully scrutinizing every dollar allocated to transit. Similarly, we try to solve our commuter traffic problems by building highways instead of railways, even though it takes fifteen lanes of highway to move as many people as one lane of track. This predisposition toward automobile use is plainly evident in the prevalent terminology: money spent on roads is called "highway investment," while money spent on rails is called "transit subsidy."
The American Gosplan is not a conspiracy so much as a culture — albeit one strongly supported by pervasive advertising — and it is probably unrealistic to hope that legislators will soon take steps, such as enacting a substantial gasoline tax, to allocate fairly the costs of driving. Pressured by generous automobile industry contributions on the one hand and a car-dependent public on the other, politicians have lately been using gas-tax elimination as an election strategy, with some success. But there is encouraging information suggesting that a gas tax may not be the political suicide that most politicians suspect. According to a recent Pew Foundation poll, 6o percent of those asked favored a twenty-five-cent-per-gallon gas tax to slow global warming.
While there are many supposedly 'anti-business" arguments for higher gas tax — from fighting global warming to supporting public transit — the real justification is economic: subsidized automobile use is the single largest violation of the free-market principle in U.S. fiscal policy. Economic inefficiencies in this country due to automotive subsidization are estimated at $700 billion annually, which powerfully undermines America's ability to compete in the global economy. Although suburban sprawl is the concern in this book, it is not the only sad result of this fundamental error.
The problems of automobile subsidization have been well documented; this is old news. And yet it is news which few people seem to understand, and which has barely begun to influence government policy in any significant way. So, to all the concerned activists nationwide who are banging their heads against the wall on this issue, we do not have very much to say except "May we join you at the wall?" Fortunately, the automobile subsidy is only one of many forces contributing to sprawl, and there are other avenues along which anti-sprawl efforts are likely to achieve meaningful results.
Re: Norman Transportation Plan "Moving Forward"
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Originally Posted by ChargerAg
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