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Slow Is Beautiful:
Speed Limits as Decisions on Urban Form

A Preservation Institute Publication


  Contents:


A Preservation Institute Policy Study
© 1996, 1997


Speed Creates Distance

The history of the American city makes it clear that we have reached the limits of economic growth. At first, growth made our cities more livable; but during the last few decades, we reached a point where growth began to make our cities less livable.

Before the nineteenth century, all cities were built as "walking cities."1 Because they had to be compact enough for people to get around by foot, cities were made up of three to six story buildings. People lived in apartments and in rowhouses that were less than twenty feet wide. Streets were narrow, buildings were not set back from the sidewalk, and there was often shopping on the ground level. The older parts of European cities and towns are still built in this form, and the earliest American cities were just as intense and congested: the streets of eighteenth century Philadelphia looked like the streets of London, though there were vast areas of open land nearby.

Early in the nineteenth century, steam powered ferries and horse-drawn omnibuses let the American middle class move to lower density rowhouses. The new neighborhoods typically were made up of three-story rowhouses: streets were wider, houses were set back a few feet from the sidewalk and had larger backyards, and trees were often planted along the sidewalks. Lots were larger: a house was commonly built on one-twentieth of an acre.

Beginning in the 1870s, horse-drawn streetcars on steel tracks, cable cars, and electric trolley cars let the middle class move to what we now call "streetcar suburbs."2 These neighborhoods were made up of free-standing houses, with sizable backyards, small front yards, and front porches facing on tree-lined streets. Houses were commonly built on one-tenth acre lots. Today, we think of these as the classic American neighborhoods.

Streetcar suburbs felt spacious and quiet, but their most important form of transportation was still walking -- even though they were one-tenth the density of the "walking city." Streetcars were used for commuting to work and for occasional trips to other parts of town, but everyone lived within walking distance of Main Street or of a neighborhood shopping street. Though you could catch a streetcar on the main street, you usually you did not have to, because you could find shopping, doctors' offices, and other everyday services right there in your neighborhood. As they walked to the main street, people nodded to neighbors sitting on their porches, and they invariably met people they knew at the neighborhood stores.

As astounding as it might seem today, most middle-class Americans who lived in cities or small towns did not own vehicles one-hundred years ago. Maintaining a carriage was a sign of wealth, and was beyond the means of the middle class. Booth Tarkington's novel Seventeen gives us a good picture of the way of life in middle-class towns and streetcar suburbs.3 At the beginning of the book, a teenage boy is walking home from the soda shop on Central Avenue. When he gets home, he finds that his mother has bought some wash tubs at an auction. Because the store that sold them is going out of business, it will not deliver and the tubs must be picked up by the end of the day, so there is no time to hire a delivery man; the boy has to walk a mile and a half across town and carry the tubs home. It is only in this sort of extraordinary situation that the family is inconvenienced by not having a vehicle. The book was written in 1915: it was not so very long ago that American teenagers walked to the local shopping street rather than driving to the mall.

Many people like cities, but for those who prefer a suburban way of life, technology and growth brought real benefits during the nineteenth and early twentieth century. From the walking city, to the rowhouse neighborhood, to the streetcar suburb, middle-class neighborhoods became greener, quieter, more spacious, healthier, safer for children.

As the twentieth century progressed, Americans moved to even lower density suburbs. After World War I, middle-class neighborhoods were built around the automobile, and they were made up of bungalows on one-sixth-acre lots: often, the neighborhood stores were not quite close enough to walk to, so people drove a few blocks to buy their groceries. After World War II, middle-class neighborhoods were rebuilt around freeways, and they were made up of suburban homes on quarter-acre lots: to get to a shopping center to buy groceries, people drove on high speed arterial streets, where the traffic was nerve racking.

Yet consuming all this extra land and transportation did not make the suburbs more livable. The automobiles made neighborhoods noisier, more congested, and less safe for children. The nearby farmlands and open space that attracted people to suburbia were replaced by freeways, strip malls and tract housing. The old sense of community disappeared, as local shopping streets were replaced by anonymous regional shopping centers. Today, suburban neighborhood groups invariably organize to stop new suburban development near their homes; everyone knows that this style of urban growth makes cities less livable.

The most important trend in urban design in American today is a reaction against modern suburbia, which is called the New Urbanism or Traditional Neighborhood Design.4 Architects such as Andres Duany and Peter Calthorpe are building neighborhoods modeled on the streetcar suburbs that were built in America before World War I. When Duany first built this sort of neighborhood at Seaside, Florida, real estate experts predicted that the houses would not sell -- they did not see why anyone would buy a house at Seaside, when they could pay the same amount and get a house on a third of an acre lot in a conventional suburb -- but Seaside was a tremendous success, because home buyers wanted the sense of community that you have when you can walk to the town center or sit on your front porch and see neighbors walk by. Several cities and counties have adopted Traditional Neighborhood Design zoning ordinances as alternatives to their conventional suburban zoning, so developers are not required by law to build low-density, automobile centered suburbs, as they still are in most of the country, and a couple now require Traditional Neighborhood Design rather than conventional suburban development.

Post-war suburbia, with housing on one-quarter or one-third-acre lots, is less livable than the streetcar suburbs built before World War I, with housing on one-tenth acre lots. All the extra land that we consumed to build suburbia did not give us more livable neighborhoods.

Likewise, all the transportation that we consume to travel through suburbia -- the freeways and the two or more family cars -- did not make it more convenient for us to get around. As speeds increased, suburbs sprawled further and malls got bigger, so people commuted further to their jobs and drove further to go shopping.

Research has shown that the amount of time that Americans travel to work has remained constant since the 1840s, when suburbanization began, despite the vast changes in technology since then.5 The total amount of time that people budget to transportation also tends to remain constant: Americans travel about 1.1 hours per day.6

In Great Britain, where there is a very active anti-freeway movement, a recent report led the Dept. of Transport to adopt a guidance document saying that cost-benefit studies on new freeways must assume that elasticity of demand with respect to trip speed is as high as 1.0 -- that is, that travel increases proportionally to increased speed, so that time savings can no longer be claimed as a benefit of freeway construction.7

In the United States, cost benefit studies assume that freeway construction has no effect on trip length: they begin by projecting development patterns and travel demand on the basis of current trends, and then calculate how freeways will effect the amount of time it takes to travel the projected distances, so that they count time savings as a major benefit of new freeway construction. But this is beginning to change: at the annual meeting of the Transportation Research Board in Washington, D.C. in January of 1997, Kevin Heanue, the Federal Highway Administration's director of environment and planning, said that an FHWA study of Milwaukee found that traffic created by new highway capacity between 1960 and 1990 wiped out 8-22% of the time savings the new capacity had afforded. But at the same meeting, professor Mark Hansen of the University of California said his studies of highway expansion in California showed a 10% increase in highway lane-miles induced an immediate 2% increase in traffic at the county level, and a 6% increase within two years. When he also counted induced traffic in neighboring counties, Hansen found that a 10% increase in highway capacity induced a 9% increase in distance traveled.

Planners are beginning to realize that higher speeds do not save people time. They just encourage people to travel longer distances to lower density suburban homes and to bigger regional shopping malls. Speed creates distance.

Limiting Growth

Modern suburbia places a tremendous economic burden on the average American. Americans spend about 50 percent of their disposable income on housing and transportation, and most have no choice but to live in low-density suburbs, where families absolutely need two or more cars. During the post-war period, the federal government actively promoted this sort of development in order to stimulate the economy and create jobs: the FHA only insured the mortgages of new suburban homes, and the Highway Trust Fund provided a constant flow of funding for new freeways. Today, most zoning laws still require automobile-dependent suburban design -- low-density housing separated from other uses, so residents cannot walk to shopping and other basic services.

Yet the extra costs of suburban housing and transportation no longer increase our well-being. During the nineteenth and early twentieth century, neighborhoods became more livable, as the middle class moved from the walking city, to row houses, to streetcar suburbs, but by World War I, middle-class Americans were already living in neighborhoods that were adequate. The streetcar suburbs gave families enough space, enough privacy, enough quiet, a big enough yard. Modern suburbia does not bring any significant added benefit, despite all the extra land and transportation it requires, but it does bring significant new environmental and social problems -- such as air pollution, the depletion of fossil fuels, automobile accidents, congestion, the ugliness of shopping strips and parking lots, the loss of farmland and open space, the breakdown of community as local shopping is replaced by regional malls. We have reached a point where the costs of urban growth outweigh its benefits.

By now, it is widely recognized that we must limit growth to make our cities more livable.

One useful tactic is the Urban Growth Boundary, which has been required in Oregon since the 1970s and is being imitated elsewhere. Oregon required towns to forbid urban growth beyond this boundary line in order to preserve agricultural land and open space, but the Urban Growth Boundary has also made Portland, Oregon, the most livable city in America. It let the city concentrate new development in downtown and in pedestrian-oriented neighborhoods built around light-rail lines. Portland now has the most interesting street-life on the west coast: refugees from Los Angeles say that their neighborhood shopping streets are so lively that they go walking in the evening. Even The Wall Street Journal, not usually known for being anti-growth, has said that Portland's Urban Growth Boundary has made it an "Urban Mecca,"8 so livable that planners from all over the country are coming to study it.

It is also widely agreed that we also need to limit automobile use to make our cities more livable. Most of our cities' environmental problems -- such as noise, congestion, and air pollution -- are costs of automobile use.

Pricing is Not Enough

Environmentalists often say that we should tax driving to make drivers pay the full cost of automobile use. Currently, for example, America's hidden subsidies to parking alone are worth about $250 billion per year.9 Several recent studies by environmental groups concluded that to eliminate this sort of direct subsidy and also to require drivers to pay for the environmental damage they cause, we would need a gasoline tax of about $5.00 per gallon.

Economists call this sort of hidden subsidy an "external cost," because it is not paid by the person who makes the decision about whether to drive. It is clear that people drive more than the economic optimum, because the automobile is more convenient for the person who uses it but creates more external costs for society than other forms of transportation. For example, it is more convenient for most people to drive to the grocery store than to walk, take the bus, or bicycle; but driving to the grocery store creates more noise in your neighborhood, more danger to children playing on your neighborhood streets, more congestion on the arterial street leading to the grocery store, and more congestion in the grocery store's parking lot, than any of these other forms of transportation. When people make the decision about whether or not to drive to the store, they think about their own convenience, and not about these social costs.

Imagine a freeway where congestion has slowed traffic to 30 miles per hour, but where people could travel at 60 miles per hour if there were 20 percent less traffic. Let's say that the average trip would take a half an hour by car at 60 miles per hour, one hour by car at 30 miles per hour, or two hours by bus. If 20 percent of the drivers decided to take the bus, it would take them an hour longer to get where they were going, but they would save the other 80 percent of the drivers a half hour each. As a result, it would take less time for all of the travelers combined to get where they are going.10 Even ignoring the environmental costs of automobile use, we can see that transportation would be more convenient overall, in this example, if 20 percent of the people took transit -- but people will not take transit and double their own travel time, in order to save time for other drivers.

This is why economists say we should have "congestion pricing." If we charge extra to drivers who use bridges or freeways during peak hours, we make them pay for the congestion they create for other drivers, and we give them an incentive to use alternative transportation and make the entire transportation system function more efficiently. This extra fee internalizes the external cost that they create for other drivers, makes them pay this cost out of their own pocket.

Likewise, if we make drivers pay for the noise, air pollution, and other environmental costs they create -- and for parking, road maintenance, and other costs that are subsidized directly by the public -- then people will choose to use other forms of transportation when the benefit of driving to themselves is less than the full cost of driving -- both the cost to themselves and the cost to the public. For example, they might bicycle to the grocery store if they only have one or two things to buy, and drive only if they have heavy packages to bring home. According to economic theory, this will optimize overall well-being: people use their cars only when the benefit of driving is greater than the full cost of driving, rather than ignoring some costs because they are borne by other people.

It does make sense to end subsidies to the automobile, but it is wrong to think that pricing policy is the solution to excessive automobile use. Economists think of pricing as a way of optimizing the use of resources at any level of income; as growth continues and income increases, they expect that people will be better off economically, because they will be able to spend more on all goods and services. But this way of thinking no longer makes sense when we realize that we have reached the limits of growth.

The economist Fred Hirsch uses cars and suburbs as prime examples of what he calls "positional goods,"11 goods that are most useful when you have them and other people do not. There was a tremendous advantage to having a car early in this century, when they were still rare -- you could get to work, shopping, and unspoiled parts of the countryside much more easily than anyone else -- but, as more and more people got cars, the traffic became slower, it became hard to find parking where you worked and shopped, and the unspoiled countryside was paved over. Likewise, the first auto-oriented suburbs made it easy to live near the country and drive to the city, but as more and more suburbs were built and the city stretched on endlessly, it became more difficult than ever to live near the country.

Now, imagine that we made drivers pay all the externalized costs of the automobile, and the higher price cut driving in half. If you were wealthy enough to drive whenever you wanted, your automobile would be a pleasure again. There would be no congestion or parking problems. It would be much easier for you to go to work or go shopping than for people who cannot afford to drive. Everyone would want to earn more money, so they could afford to drive more -- and growth would continue until driving became such a misery that we had to raise its cost again.

Because driving and suburban housing are positional goods, people will keep spending more money on them indefinitely in order to get ahead of everyone else. Charging people more to drive would actually increase the pressure for economic growth: people would want to step us the growth rate and earn more money, so they could drive more.

Limiting Speed

To end growth, we need to put direct limits on automobile use, and the simplest way to do this is by limiting speed. As we have seen, increasing speed in the past simply increased the distances people traveled: because the time people spend traveling remains constant, higher speeds generated suburban sprawl far from where people worked and regional shopping centers far from where shoppers lived. Contrariwise, gradually reducing the speed limit for automobiles would not only shift longer trips to public transportation; even more important, it would encourage people to shop locally rather than regionally shopping, and to live nearer to where they work. Increasing speeds generated suburban sprawl by letting people travel further, and reducing speeds would stop and ultimately reverse sprawl.

Speeds should be reduced outside of cities as well as in the city: it should be clear by now that it was a mistake to build freeways through all our rural areas. The freeways turned much of our countryside into exurbs filled with commuters: for example, much of southern New Hampshire is now essentially a suburb of Boston. Because they were designed to speed transportation, the freeways by-passed small towns: all over the country, new developments near the interchanges drained business from nearby Main Streets. By fragmenting the open countryside, the freeways reduced wildlife populations.

We should reduce the speed on these freeways and ultimately replace them with ordinary rural roads, with a speed of thirty-five or forty miles per hour -- with curves to keep traffic down to the speed limit and with traffic lights or stop signs rather than overpasses where roads cross. When these roads go through the Main Streets of towns, they should be slowed to the speed of local traffic: they would bring Main Streets more business, rather than bypassing small towns to keep traffic moving quickly, as freeways do. Slowing down automobile travel would shift long-distance travel and freight to high-speed rail: there are abandoned and semi-abandoned tracks all over the country that could be upgraded relatively inexpensively, without the cost of purchasing new rights of way. Roads would be used primarily by local people and for pleasure driving: you would actually get a feel for the countryside and the towns as you drove through them-rather than just feeling the monotony of driving on a freeway. Small towns that have been neglected during the last fifty years would revive, once they had a railway station in the center of town and cars driving through on Main Street.

Limiting automobile speeds would help restore our small towns and countryside, but it can do even more in the city. The next two sections will look at a number of different limits on the automobile in the city, to see what effects they would have on the city's form. First, we will look at the most extreme, a ban on automobiles in the city, to show clearly how wasteful the automobile is, and then we will look at some less stringent limits on the automobile. After looking at these ideal types, which show what cities would be like if automobile use were limited in different ways, we will look at how to begin changing our existing cities.

A Traditional City

Our cities would be most livable if we reduced speeds enough to ultimately phase out automobiles completely as a form of in-city transportation. City dwellers would still use cars for recreational trips to the country, and motor vehicles would also be used for deliveries and other services. But walking, bicycling, mini-buses, light rail, and commuter rail would be used for in-city personal transportation.

Banning cars and limiting the scale of development could give us cities that look like the better neighborhoods of American cities early in the century. Because the country is wealthier now, almost everyone who wanted to could live in neighborhoods like the streetcar suburbs where the minority of Americans who were middle class lived before World War I, when middle-class Americans did not own vehicles. The streetcar suburbs are widely considered a high-point of American urban design, with their tree-lined streets of private houses, with shopping and trolley lines within easy walking distance, and with stores that offer delivery of groceries and heavy goods. Yet many people would also want to live in neighborhoods of row houses or of apartments, once these higher density neighborhoods were no longer overrun with cars.

It would be possible to provide very frequent transit service in these compact cities, where private automobiles do not compete with public transportation. We would also expect many improvements on the bicycle to appear, once people no longer could drive, such as bicycle trailers to carry small children or cargo and pedi-cars, with light-weight convertible roofs made of aluminum and nylon, that you could use on rainy days. Even more important, people would not have to use as much transportation: it would be quicker to walk to the local store or doctor's office than it is for modern suburbanites to drive to the shopping mall or medical center.

Compare this city with the cities we have today. It obviously would be more livable -- quieter, safer for children, cleaner, and more neighborly. And it would be about as convenient as our cities today: people would spend the same amount of time getting to work, to shopping, and to other destinations.

Yet it would cost far less than our cities do today. Americans now spend about 20 percent of their disposable income on their cars, and virtually all of this cost would be eliminated, because trip lengths would be so much shorter. In addition, Americans now spend about a third of their income on housing, and housing would be much less expensive because of reduced land and parking costs: land cost now represents up to 40 percent of total housing cost in the country's most expensive housing markets, and over three-quarters of this cost would be eliminated. There would also be savings because of shorter utility lines, because businesses would not need to provide "free" parking and public agencies would not need to acquire land to stop sprawl, and so on. There would be some increased costs-for example, because stores would be smaller-but there would be tremendous savings.

Americans spend about one-half of their disposable income on housing and transportation.12 We could save about half of this by walking and living in streetcar suburbs that are more livable on the balance than modern suburbia. The trillions and trillions of dollars that Americans have spent on suburban homes, cars, freeways, and parking lots do not make the average person any better off.

Proposals to ban cars used to be ridiculed as unrealistic, but there are now auto-free zones in the centers of most European cities, and the majority of voters in Amsterdam recently decided to ban cars from the entire central part of that city, with about 10 percent of its land area and 15 percent of its population. This plan is more sweeping than anything that has been proposed in the past, and environmentalists believe that other cities will imitate it if it is successful.

Speed Limits and Urban Form

It is also plausible to aim at less stringent limits on automobiles than a total ban.

As a second ideal type, to illustrate the effect of different limits on the automobile, consider a speed limit of 15 mph for private vehicles within a city, which would let people use cars for local errands but shift them to higher speed public transportation for longer trips. Because of the low speeds, automobiles would no longer dominate transportation and exclude other users: bicycles and small electric vehicles similar to golf carts could travel along with the automobile traffic. Shopping streets with slow traffic would be friendlier to pedestrians; and traffic would be slowed down even more on neighborhood streets, to make them safe enough that children could play in them.

With this sort of speed limit, there would be a massive shift to public transportation for commuting and for regional shopping. Development would naturally tend to cluster around transit nodes and corridors, in order to appeal to customers and clients who use public transit. Because it would take longer to get to regional shopping, most every-day shopping that is now is done in regional malls would shift to local shopping streets instead; but you would have some auto-oriented stores on these shopping streets, instead of old-fashioned, pedestrian-oriented stores: shopping streets would be fragmented by occasional supermarkets with big parking lots. Though densities would not be as high as they were in the Victorian streetcar suburbs, they would be higher than in modern American suburbia.

This city would have some of the advantages of streetcar suburbs, such as nearby shopping streets and good transit service, though it would be less neighborly, less compact, and noisier. It would also have some of the advantages of suburbia: automobiles would let people live in neighborhoods with larger lots, haul loads of groceries to the basement deep-freeze, chauffeur children around, and generally live a more suburban way of life.

As a third ideal type, consider a city with an even looser limit on automobile use, an in-city speed limit of 30 miles per hour. Even this mild speed limit would do much more to solve our cities' problems than the elaborate regional land-use and transportation planning that environmentalists are calling for.

Long-distance commuting that is now done by freeway, would shift to public transportation on high-speed rail systems. Commercial development would tend to cluster around the rail stations, to take advantage of the regional workforce and customer base that comes by rail: freeway oriented regional shopping malls would be replaced by mixed-use shopping and office complexes (with plenty of parking) at rail stations. Some of the suburban sprawl at the edges of the metropolitan area would also recede, because it is totally dependent on high-speed freeway access and would be isolated without it.

None of the environmentalists who call for regional governments and massive planning bureaucracies expect as much from them as you could get from a simple law limiting automobile speed to 30 miles per hour.

Yet this speed limit would allow everyone to live a suburban life: if the city had a high speed rail system, people could live in residential neighborhoods that look like post-war suburbia. The main differences in everyday life would be that people would shop and work in mixed use complexes near transit stops, which are more interesting than shopping malls and office parks, and that most people would commute by high-speed rail, which would make most commutes less grueling. These changes would cut automobile use in half, dramatically reducing the city's environmental problems.

In the past, American cities have been suburbanized by default. People fled from the city to the most remote, lowest density suburbs they could afford, without thinking about the effect they were having on the region as a whole; planners accommodated this trend by building as much suburban housing and as much transportation as possible; and there was no political control on urban development. By contrast, a speed limit of 30 miles per hour represents a deliberate, responsible political choice of a suburban way of life: it would let everyone live in suburbia without totally blighting the region with freeways, parking lots, and traffic congestion.

It has also become common in to limit speeds in European cities, using what is called "traffic calming." In the Netherlands and Germany, many residential streets have been converted to Woonerfs, redesigned to slow traffic to five or ten miles per hour. Traffic calming on residential streets has also begun in the United States, generally using simple and inexpensive methods such as speed humps, gradual undulations in the road, which make it uncomfortable to drive more than 15 miles per hour: the city of Oakland, CA, recently began a study to determine the best way to protect residential streets from traffic, but there was such strong neighborhood pressure for immediate action that the city decided to install speed humps in five hundred locations all over the city before even beginning the study.

In the 1980's, Germany took a step beyond these schemes to control traffic on residential streets and began what is called "Area wide traffic restraint," slowing traffic on all the streets in an area-major streets and highways as well as local residential streets. The Federal government calmed traffic in six areas experimentally, ranging from an area in Berlin with 30,000 residents to a small town of 2,300 residents. They found that average speeds were cut almost in half but that the time for the average trip increased by just a bit over 10 percent: obviously, one major result of traffic calming was to shorten the length of the average trip. In addition, noise levels and injuries from automobile accidents dropped dramatically.

The German automobile association, which was skeptical about the government's data, did interviews and found that, after speeds were lowered, 67 percent of motorists and even higher proportions of residents approved of the change. The German experiment in area-wide traffic calming was so successful that it has been imitated in cities in Denmark, Sweden, the Netherlands, Italy, Switzerland, Austria and Japan. Some experiments in area wide traffic calming have reduced traffic by 30 to 50 percent.

The First Steps

Limiting speeds would have to be a gradual process in the United States. Area-wide traffic calming is easy in Germany, which already has compact cities where it is easy for people to make shorter trips, but we would have to rebuild American cities as we lowered speeds. American metropolitan areas are so freeway dependent that they might begin with a speed limit of 45 miles per hour and gradually reduce it further, at the same time as they built better transit systems and more infill development.

It is usually easy to reduce speeds on local streets, since there is already neighborhood pressure to make streets safer. The time is also ripe to slow traffic on arterial streets, because transit providers are beginning to restore light rail lines on the major streets of many cities. Transit providers have begun to suggest that we can improve transit service on arterial streets by allowing transit drivers to preempt traffic lights with electronic devices that turn the light green as the bus approaches: lights on these streets are currently timed to speed automobile traffic, so that these devices would slow down automobile traffic as well as speeding up transit. Transit providers have also suggested several other methods of speeding buses that would also slow traffic, such as reserving some lanes exclusively for transit.

It is much more difficult politically to slow traffic on freeways. Ideally, we would slow traffic on freeways gradually, perhaps by adding traffic lights to meter traffic on the freeways, which could be timed to keep traffic at the speed limit. By the time the speed is slowed to 30 miles per hour, traffic would be reduced enough that we could take the next step by replacing the freeway with an urban boulevard that enhances the neighborhoods around it.

In practice, it is more likely that we will reduce freeway capacity by fighting plans to rebuild freeways as they obsolesce. A waterfront freeway in San Francisco, for example, was demolished and replaced by a grand boulevard after it was damaged by an earthquake, largely because of environmentalist pressure.

This was a spur that did not carry much through traffic, but environmentalists have proposed more dramatic changes. When New York City announced that the Gowanus Expressway had to be built, local activists pointed out that this elevated freeway destroyed the shopping district on the street below it when it was built, and encouraged more people to move to the suburbs. Instead of rebuilding the freeway, they proposed removing it and restoring light rail to the street below, with connections to nearby bridges and tunnels. This would not only revive the shopping street: it would also be a step toward changing the city's entire transportation system.

Even more dramatically, Swiss voters passed initiatives in 1994, despite opposition from their own government and from European Community transportation experts, to ban all freeway expansion and to phase out all truck traffic through the Alps in ten years, in order to force all freight onto rail. This direct political action to limit freeway use is clearly better than the result the we would gotten if the Swiss had considered this issue a technical problem in transportation planning and placed in the hands of a regional planning authority.

Choice of Technology

Now that we have looked at three different limits on the automobile, and at the three different types of city that they would create, it should be clear that there are fundamental political questions underlying the technical questions that transportation planners deal with. A ban on automobiles would create pedestrian-scale neighborhoods; a 30 mile per hour speed limit would create suburbia. These different neighborhood designs involve different ways of life, and so this choice of technology is a political decision, rather than a technical decision that should be made by experts in urban planning.

It should also be clear that putting political limits on large-scale development and on speed would make it much easier for the planners to solve our cities' problems. Some planning would still be needed, even with a total ban on automobiles: we would still need regional or sub-regional planning to lay out transit lines, control air and water pollution, run large park systems, reserve areas for nuisance industries and the like. With less stringent limits on automobiles, we would need even more planning. Yet even with a 30 mile per hour speed limit, it would be much less difficult than it is today to build an effective transit system, control pollution, and protect the region's open space.

Technocratic planners have always called for comprehensive regional planning to solve our urban problems: a single regional planning authority should be responsible for land-use and transportation planning, so it could deal with all of the region's problems in a coordinated way. Regional government should replace the "irrational" patchwork of city, county and state governments, because political decisions should be subordinated to the technical tasks of planning.

In fact, to reclaim our cities, we need to do the opposite of what the technocrats say: we need to recover the political use of government and use the law to limit technology. We do need some special-purpose regional planning agencies that cut across local jurisdictions and are responsible for transportation, for air and water pollution control, and the like, but we do not need a comprehensive regional planning authority to manage all of the region's planning. Instead, we need to begin making responsible political decisions to limit technology, which would leave the planners with manageable problems, which they actually have some chance of solving. If any city makes the decision to lower speeds on its streets, it will help to reduce the entire region's transportation problems. And using the law to set lower speed limits has an important political advantage over technocratic planning: rather than making ordinary people more powerless and dependent on the experts, it gives them more power and more responsibility.

Footnotes

1 Kenneth T. Jackson, Crabgrass Frontier: The Suburbanization of the United States (New York, Oxford University Press, 1985) pp. 14-20.

2 See Sam B. Warner, Jr., Streetcar Suburbs: The Process of Growth in Boston, 1870-1900 (Cambridge, Mass., Harvard University Press and the MIT Press, 1962).

3 Booth Tarkington, Seventeen: A Tale of Youth and Summertime and the Baxter Family Especially William (New York, Harper Brothers, 1932).

4 For an overview of this movement, see Peter Katz, The New Urbanism (New York, McGraw-Hill, 1994).

5 McLynn, J.M. and Spielberg, "Procedures for demand forecasting subject to household budget constraints" in Directions to improve travel demand forecasting: conference summary and white papers: HHP-22 (Washington D.C., Federal Highway Administration, 1978) pp. 115-197.

6 Ryan, J.M. and Spear, B. D., "Directions toward the better understanding of transportation and urban structure," in ibid., pp. 199-247.

7 U.K. Dept. of Transport, Report of the Standing Committee on Trunk Road Assessment, December 1994 and Guidance document 24 L, based on this report. In the United States, Robert Johnston of the Institute for Transportation Studies at the University of California at Davis has developed a computer model that includes a feedback loop to account for the fact that people travel longer distances when they can travel at higher speeds and travel time tends to remains constant. Several cities have already used this model, and Johnston says that, if it is widely adopted, it will become virtually impossible to increase freeway capacity. For a more general discussion of the feedback loops that need to be added to current transportation models, see Peter Newman and Jeffrey Kenworthy, "The Use and Abuse of Driving Cycle Research: Clarifying the Relationship between Traffic Congestion, Energy, and Emissions, Transportation Quarterly, vol. 30, #4, October 1984, pp. 615-635.

8 Wall Street Journal, Dec. 26, 1995, p. 1.

9 Michael Replogle (Environmental Defense Fund), "A Transportation Pricing Overview," Surface Transportation Policy Project Progress, November, 1996, p. 3.

10 If everyone drives, X people require one hour each for a total of X hours of travel time. If 20 percent take the bus, then the .8X people who drive take one half hour each (requiring .4X hours of travel time), and .2X people who use the bus take two hours each (requiring .4X hours of travel time) for a total of .8X hours of travel time.

11 Fred Hirsch, Social Limits to Growth (Cambridge, Mass, Harvard University Press, 1976) pp. 27-31 and 36-40.

12 According to the U.S. Bureau of Labor Statistics, in 1988, the average American family earned $25,892 after taxes, and spent $5,093 on transportation and $8,079 on housing.

 
The Natural Environment: The Social Environment