This is a really excellent book, probably the best overview of the issues that I've read so far. The authors put automobile dependence in context within larger environmental debates about sustainability, and they bring to the discussion a deep understanding of the links between transportation and land use. They cite a lot of literature, and come to the same conclusions that I've reached after a year of reading on this issue. Unlike their earlier seminal work [37,25], this is not an exercise in data collection and analysis, but instead more of a discussion of the "big picture" issues.
I've typed up quite a few of my notes in this book, but they can't come close to capturing the thread of the arguments. Just go and read it yourself!
The data on city size were clear in our original global cities study . This thirty-two-city survey showed the same pattern: transport energy use per capita generally declines as city size increases. Peter Naess from the Norwegian Building Research Institute wanted to investigate this phenomenon by eliminating the major variable of cultural difference that so clearly influences a survey of global cities. He chose twenty-two Scandinavian cities and found a very clear relationship between the size (as well as the density) of the city and its per capita transport energy use. The cities of Copenhagen, Oslo and Stockholm were significantly lower in transport energy use per capita than were smaller provincial towns [31,32].
For decades, urban economists have been pointing to the efficiency advantages of scale as well as of density (the two are generally linked). There have been many studies of cities that have found significant economic benefits arising from increased scale and density [17,18,45,42]. The benefits in terms of sustainability come from the same kind of economic efficiencies that are applied to environmental technologies—e.g., public transport systems become more efficient as cities grow; waste treatment and recycling systems become more efficient as cities grow (all other factors being equal).
There are economists such as Neutze [35,34] who point to the diseconomies associated with size due to the growth in externalities. Others stress social problems that are said to increase with city size and density . The data on this question are usually very sparse, however, and the issue seems to be dominated by ideological stances . Fischer  summarizes the elusive search for optimal city size in the following way:
Most urban scholars seem convinced, to quote a British economist, that "... the search for an optimal city size is almost as idle as the quest for the philosophers' stone" [42, p. 131]. The entire area of speculation is misconceived on several grounds. First, there are no substantial empirical findings pointing to city size at which any "good"—income or innovation or governmental efficiency—is maximized, or any "bad"—crime or pollution—is minimized. In fact, some data suggest that for economic purposes an optimal city size would be larger than any we now have. We have certainly not identified an optimum size for any social-psychological variable in this book. Even if such ideals could be found, they would probably not be the same for a wide variety of social products. The size that maximizes personal incomes would differ from that which maximizes artistic creativity, or that which minimizes pollution, and so on. And it would surely be a vain task to try to sum up all these various "goods" and "bads" into a single measure.
They repeat their history of urban form from ; still good to read, of course. They extend some of those ideas by discussing the new urban frontier:
Frost , an Australian economic historian, shows there were two distinct types of Western city in the nineteenth century and into the twentieth century: (1) the "traditional" high-density cities of Europe, east coast North America, and east coast Australia (London, Paris, Berlin, St. Petersburg, New York, Philadelphia, Chicago, Sydney) and the low-density "new frontier" towns of western and southern North America and Australia (Los Angeles, San Francisco, Seattle, Denver, Melbourne, Perth, and Adelaide).
The reason for this difference is not just time of development, since new cities in these regions followed both patterns. Frost suggests that the major difference was the way the two types of cities used their capital. The "traditional" city directed a high proportion of its capital accumulation into industrial plant and had little left for urban infrastructure; hence housing was dense. The "new frontier" city directed a far higher proportion of its wealth into suburban infrastructure, thus enabling low density to be the major form of housing.
The differences in capital availability came from the different wealth base: the "traditional" city developed wealth from an industrial base for import substitution and innovation; the "new frontier" city developed wealth by servicing a large rural hinterland.
Newman and Kenworthy divide transportation professionals in a manner I haven't seen before:
Each of the issues listed [...] has a large following of technically oriented people who believe that through incremental, largely technological change, these constraints can be managed. However, they often produce solutions that worsen other problems. Equity problems, for example, can be eased by increasing car ownership and reducing fuel costs, but this increases economic, environmental, and livability problems. Minimizing traffic impacts with buffers and noise walls rather than modal shifts just increases the other automobile-based problems. Easing air pollution by designing highly efficient, low-emission vehicles can extend automobile dependence.
Such incremental changes are based on the assumption that the kind of city we now have is essentially adequate to meet future challenges. We don't believe it is.
They go on to describe the two camps, those who believe in an "incremental" approach to correcting problems in the transportation system, and those who prefer an "urban systems" approach. The first camp is filled with the traditionalists: they admit that the status quo doesn't work, but foresee only minor changes to fix the problems. The urban systems group, on the other hand, sees a need for a much larger rethinking, and a move away from a reductionist philosophy to a more integrated "systems" mindset, considering many issues simultaneously.
From what I've read, I think many professionals and intellectuals currently straddle these two camps. In particular, the economists (e.g. Moore and Thorsnes  or Downs ), are starting to think in a systems view when it comes to transportation/land use interactions, but have yet to accept the need to adopt the social or environmental ideas suggested by Newman and Kenworthy. Overall, they're much closer to the incremental group than the urban systems group. Todd Litman is perhaps the one exception; I think he's given a lot of thought to equity and active transportation, and I would put him in the urban systems camp.
Overall, I don't think this division is a very realistic representation of the overall divisions in the transportation community right now. However, I think this is where the debate is headed: a showdown between these two visions of the future. On the one side, those who believe in minor changes to the system, and a continuing large role for the car; on the other, those who envision large-scale modal shift. Count me in the urban systems group.
Below is their definition of the philosophies of the two groups. I found the "loss of community" section particularly interesting, especially their emphasis on unplanned interactions during travel.
|INCREMENTAL APPROACH||URBAN SYSTEMS APPROACH|
|Infrastructure costs will be reduced by proper pricing and new technology, but will continue to be car-based.||Capital will still be wasted (even if it is private money) if development is low-density and scattered (car-dependent) rather than focused and transit-oriented.|
|By pricing operations adequately there will be an efficient allocation of resources, and the more flexible the technology the better.||Pricing and flexibility are only one part of the equation since the urban system could become totally car-based with minimal transit; regulations and planning need to be redirected to ensure that the total system works as well as the separate parts, and this means fixed-rail systems that facilitate more concentrated land use.|
|Time loss is overcome by costing this into any proposed transportation projects.||Time loss cannot be addressed by transportation alone but needs land use changes that reduce the need to travel.|
|Land loss is not an issue since higher-value urban uses legitimately replace lower-value ones. Parking and road space can be more efficiently used, but the only question is to get the pricing correct.||Land loss is important in the longer term since good arable land and bush land are important resources. In a city with excessive parking and road space it is necessary to intervene and regulate such loss of urban space for social as well as economic reasons.|
|The more efficient provision of housing requires more small-lot subdivisions and simple urban consolidation such as dual occupancy.||The housing mismatch requires fundamental change as well as the incremental changes suggested. It requires a revision of building bylaws and planning schemes based more on performance and design standards than density as well as facilitating larger-scale change, such as in urban villages.|
|The oil problem will be handled by a transition to using marginal oil and then alternative fuels and by a combination of the fuel price rising and new technology being developed for both fuels and vehicles. Behavior will adapt due to these changes, rather than any other social or urban systems change.||The oil problem requires a solution that is bigger than all the incremental approaches, although it will include elements of each. The most important part of an urban systems approach to this problem is to start providing more housing and employment location choices with less in-built transportation energy requirements and with inherently less-energy-intensive modes as their base.|
|Greenhouse gas reductions will occur when prices are more appropriate, and hence technologies will begin to adjust to less fossil fuel use. Regulations could hasten this.||Greenhouse gas reductions in transportation will be assisted by pricing changes, technological approaches, and changes in behavior. However, they will be more effective in concert with urban systems changes that begin to take the growth momentum out of greenhouse gas emissions by providing housing, employment, and transport options with inherently lower greenhouse gas generation rates.|
|Air pollution from transportation will be reduced by a combination of regulations, vehicle and fuel technology, and traffic management.||Reductions in smog pollution must come from a combination of incremental approaches, such as technological improvements to cars and engines and selected improvements in the traffic system; but unless action is taken to reduce annual growth in car travel, then these approaches will be running hard just to stand still.|
|Environmental Impacts from Suburban Sprawl|
|Impacts from suburban sprawl can be minimized by zoning to preserve sensitive areas and by some urban consolidation.||Incremental approaches are part of reducing the environmental impacts of sprawl but are not enough to fundamentally slow down the momentum of environmental degradation at the fringe; only bigger changes in the density and style of urban development in new and existing areas will be able to achieve this.|
|Local Traffic Impacts|
|Local traffic impacts can be ameliorated through schemes that redirect traffic away from sensitive areas using bypasses, techniques that mask traffic emissions and the presence of cars, pricing formulas that penalize car use, and/or market responses by individuals in shifting to a better environment. Ultimately, improved vehicle technology will significantly reduce traffic impacts.||The urban systems approach contends that there is a limit to how much the local effects of increasing car numbers and car use can be ameliorated through traffic management. Such management can be enduringly effective only in the context of decreasing, not increasing, car dependence. Reducing car dependence will be possible only through urban systems changes such as area-wide traffic calming, providing inherently less-car-dependent housing and employment arrangements, building new public transportation systems, and giving priority to nonauto modes.|
|Transportation and Locational Disadvantage|
|Incremental solutions to problems of transportation and locational disadvantage possess two key features: (1) they emphasize transportation rather than land use policy approaches; and (2) they favor private cars over public transportation.||The urban systems approach to transportation and locational disadvantage favors integrated land use and transport policy solutions that reduce the need for car travel and make transit more viable.|
|Loss of Community|
|Unplanned access is not an issue in transportation planning. The only kind of access that can be planned for, or is of any practical relevance in auto-dependent cities, is deliberate access, and this is, and will continue to be, more than 90 percent by car, with the remainder by public transportation. Walking and cycling do not figure at all in traditional computer-based land use transportation planning.||The basic philosophies and practices of transportation planning need to change to recognize the crucial role played by walking and cycling (and particularly their future potential), as well as to consider the qualitative, more human aspects of access and transportation, such as opportunities for unplanned interactions, not just quantities of motorized traffic and the roads needed to cope with them.|
|Public transportation should be viewed purely in terms of its economic effectiveness and ability to cater to a diminishing market of deliberate access trips. Intangible benefits such as helping to enhance a sense of community through accidental interactions are of no real consequence.||An effective public transportation system well utilized by all sections of the community, not just the transportation disadvantaged, is not only important for planned access but also for its unplanned access and community-enhancing possibilities (e.g., through interactions among passengers and by drawing people through major activity centers along its route).|
|Loss of Urban Vitality|
|Overcoming social isolation is best left to the individual decisions and actions of families or formal urban institutions specializing in the problems of youth, the elderly, the disabled, and others. Modern communications technology is making the need for face-to-face contact less and less relevant.||Many problems, such as the isolation of elderly people and youth, as well as issues such as juvenile car-related crimes, are at least partly rooted in the way we structure our cities around compulsory car use and an emphasis on private rather than public space. Modern technologies will never replace the need for most face-to-face meetings and contacts, particularly for creative economic functions and recreation purposes.|
|Loss of Public Safety|
|The safety of the public realm is maintained by greater use of police.||Safety requires policing to be a partnership with communities, thus protecting and enhancing the public realm of our cities through healthy and humanly attractive spaces that encourage interactions, enabling crime to be reduced through "defensible space" and the strength of community values.|
[F]uel use patterns are important for discussions about greenhouse gases: transportation-based carbon dioxide is an important issue in the post-Kyoto world. One of the immediate responses for cities is to try to reduce their use of coal. Although this is a generally positive policy to pursue, there is a twist to the greenhouse issue when cities are the focus, rather than just nations, as shown in the data here. Despite coal-based electricity being less fuel-efficient than gasoline (and being four times worse than gasoline in terms of carbon dioxide produced per MJ of transportation energy), it does not mean that cities with electric transportation are worse in energy use or greenhouse gases; in fact, the reverse is the case. This is primarily because of the nature of the technology and the effect of either the car or the train/tram on the city. [...] The mechanism for this appears to be land use changes, greater walking and cycling in transit-oriented environments, and the linking of a number of trip purposes when using transit. [...] A future based upon electric power will favor electric transit, perhaps supplemented by electric automobiles; but this must not be a one-for-one substitution of electric cars for gasoline cars because the need for energy conservation will require a substantial move toward electric transit-based cities.
These data support the notion of "transit leverage," or "transit multiplier" , which has been hinted at in the previous discussions on mobility and on fuel types. Calculations show that when transit replaces car travel, it does better than substitute 1 kilometer of car travel for 1 kilometer of transit. Neff suggests it could be anywhere from 8.6 to 12.0 kilometers of car travel that are replaced by 1 kilometer of transit based on US data. In our global cities data, it appears to be more like between 5 and 7 to 1, based on the relative decline in vehicle kilometers traveled per capita for every extra passenger kilometer travelled per capita on transit. The reasons for this multiplier effect include the following:
Transit leverage is extremely important as a concept when examining the future potential for travel pattern change. Most projections from transportation planners try to show how difficult it is to reduce car use significantly. The standard approach is to double the present amount of public transport use and subtract that from car use, thus showing only a few percent reduction for an assumed massive amount of investment [...] However, the transit leverage concept means that by building new transit and attracting users, there is a flow-on of reduced mobility that is considerably more than the extra transit passenger kilometers.
Brindle  has suggested that it is wrong to graph two parameters that are both per capita because it will always guarantee a hyperbolic relationship. It is true that the shape will be a hyperbole, but there is no guarantee that there is a statistically significant link. However, there is clearly a strong statistical link in our data between transport energy use per capita and urban density. Evill  shows that it is not spurious to do per capita correlations.
Brindle's claims are interesting, and his paper is worth reading. He shows that there is a strong statistical link between fuel use and urban area (F=kA, r-squared of 0.95 using the 1989 book's data), but this means that there is equivalently a strong link between per-capita fuel use and urban area per person ( ). Newman and Kenworthy's comments are hence valid, if a bit dismissive.
[T]here are enormous resources and human energy poured into road safety when by far the biggest gains would be made by shifting to other modes and reducing the overall level of car use. This approach is rarely mentioned in road safety discussions.
There are some exceptional cities in terms of the patterns of traffic-related deaths:
They start by dispelling 10 myths about the inevitability of automobile dependence. Most of the arguments are familiar in the literature, so I won't belabour them here, but the myths they address are:
5. Health and Social problems. [...] In contrast to the anti-density tradition there is another that has emphasized the positive human benefits of increasing densities. Freedman  developed a crowding model that tries to make sense out of the conflicting evidence from empirical studies, while also recognizing the adaptability of humans. He suggests that "crowding is not generally negative and it does intensify human reactions to other people." It stimulates human interaction, which means the human effects of density are up to us. Higher density produces negative effects if we design it that way, but we can also make higher density into something beneficial.
6. Road lobby. [...] Similar lobbies exist in all countries , but not all are as successful as in the United States. The political power of the road lobby everywhere is strong but not overwhelming; governments are accountable to the wider public as well as to the lobbyists. The influence of strong private-industry lobbies for the automobile in many European and Asian countries has been minimized by equally powerful lobbies for transit.
They mention a very different, broader philosophy of traffic calming than what I've encountered in my readings so far. I suspect this is more the Dutch approach than the Canadian adaptation...
Traffic calming can be viewed as a broader transportation planning philosophy and not merely as a series of physical changes to roads . Traffic calming in this broader sense is aimed at reducing total dependence on the automobile and promoting a more self-sufficient community with a transportation system more oriented to pedestrian, cycle, and transit use.
The broader objectives can be summarized as follows:
I was glad to see the Dutch A,B,C system that I'd encountered earlier in my reading  revisited by these authors. I'd like to learn more about this—I think North American cities should look into a similar system. They also included a diagram (which I haven't reproduced) showing A on a passenger rail line, B at the intersection of a bus route and an arterial road, and C on a freeway.
It is important to try and match the different land use requirements with the transportation system requirements. Such a process is the Dutch A, B, C system sometimes called "the right business in the right place". . The system has been adopted by the United Kingdom as the basis of its Planning Policy Guidance 13 .
The system allocates A, B, or C locations to businesses:
The city is then given different accessibility profiles depending on whether it is more like an A, B, or C location. The plan is not only to try to match business to the most appropriate transportation system, but to help create development plans that (1) facilitate business relocation, and (2) build up the transit or road system to better service the businesses with transportation (e.g., goals for transit in A locations are to become more than 80 percent of all motorized trips in and to the area).
This system can enable a city to become less automobile-dependent while ensuring that its goods production and distribution are more efficient. In the Netherlands and the United Kingdom, local authorities use the system as a guide rather than as a statutory plan.
Some of the groundwork for transit's success, as well as its ongoing achievements in Singapore, are due to Singapore's famous area licensing scheme (ALS), introduced in 1975 to reduce morning peak commuting into the CBD, and its long history of steep vehicle taxes, including the more recent certificate of entitlement (COE) system, which requires would-be car owners to bid for the right to buy a vehicle. The price of a COE varies continuously, but in early 1994 it was as high as US$47,000, on top of the car purchase price (Straits Times, December 17, 1993).
The following quote led me to look into the "blue strips" they describe, and I discovered  and the Adonis project —excellent resources for bicycle planning.
Although Copenhagen has only 300 kilometers of separated bikeways (much less than in Amsterdam and other Dutch cities), the city has created safety and priority for cyclists by much cheaper means: paint on the roads and a successful education program that generated a "culture of respect for cyclists." Thus at every intersection there are blue strips for cyclists to ride in, giving them priority over all turning vehicles.
A curious detail about the Spadina transit line and the Allen Expressway that I hadn't known about:
The location of the northern end of the Spadina subway line in the middle of the Allen Expressway has, however, inhibited the strong nodal development characteristic of other parts of the subway system—development that is clearly visible from the air as clusters of high-rise development above and around many subway stations.
When reviewing the form of cities required for achieving sustainability, Radberg  described the rationale for a more compact city that can conserve energy, very much along the lines of our work presented in Chapters 2 through 4. He then proposed the form of a city for achieving green objectives that are "related to the ecological perspective" for "recycling and cultivation"; this city is "greener, more ruralised, more spread out." He therefore raises the question as to whether there is not a conflict between the need to have more urban land for the green city in order to accommodate local ecological processing, and a low-energy city with its need to minimize travel distances and thus have a frugal use of land.
The Rural Commons View
This view says that cities are too big and need to be broken down into little pieces that should be substantially self-sufficient. Such areas are said to bring back into the city the rural values that have been lost. Thus, in these areas, the environmentally damaging and socially isolating city can become more in turn with nature through the development of local self-sufficiency. Most of the food, it is suggested, could be produced locally; most of the work could be available locally; most of the educational and recreational opportunities will be available locally; and most of the friendships and social meanings could be found locally.
The local environment orientation also is aimed at re-creating creeks from drains and creating more habitat for wildlife, as well as recycling solid waste and wastewater instead of sending them somewhere else.
In this context of a local self-sufficiency, it is suggested that a solution can be found to the heavy dependence on fossil fuels that characterizes our cities. The view is built on the assumption that a more cooperative social structure will emerge with the commons being managed for the good of all. For example, a permaculture kind of food production could occur, with backyard agriculture merging into shared management of local production. Cooperative ventures could be established to manage water and solar power, to establish and run urban forests, to develop artisan and light industry workshops, and so on.
The view is not necessarily antitechnology, and indeed it warmly embraces modern communications and home computers as ways of assisting such self-sufficiency in retaining contact with a wider world. However, little is ever said about transportation, apart from the importance of bicycles, because self-sufficiency is meant to do away with the need for larger transportation requirements. It is sometimes called the "low mobility" city, though it is only low because of radical lifestyle changes, not because of the form of the city. But its major thrust is to reduce densities and create more rural activities in the city.
The Urban Commons View
This view is concerned mostly with the city as a system. It suggests that the city should become more urban not less, contained from its sprawl, and rebuilt from within. It suggests that there is far too much wasted space in cities given over to automobiles for parking and roadway space, and that there is excessive and often greatly under-utilized private space. It suggests that the public areas, public concerns, transit, and so on should become the focus of an urban renewal based on a redesign and recommitment to the city and its public values. Central to the urban commons approach is the need to overcome automobile dependence. More than any other technology the car is seen to be the source of so many of the problems of modern cities [...].
In practical terms, the urban commons view suggests that auto-dependent cities should start to address their problems by reurbanization and reorientation of transportation priorities, but this can have significant overlap with rural commons goals concerning natural features of the city. Indeed, part of the urban commons view is to include innovative approaches to greening the city. For example, traffic calming should involve landscaping that can provide a wildlife habitat and serve as a link between parks and water systems, as well as being aesthetically important to the city. Urban villages should have trees and gardens for a quality environment and have urban agricultural production and urban forestry conducted in the public commons area. Indeed, it is believed that most greening issues will be better managed by the urban commons approach.
Thus local ecological goals can be met but the context is more global and urban. The city in this view does not need to be a replacement for the country, but it does need to be more in harmony with the environment, to use resources carefully, and to be closely designed to fit in with the local water regime, the local terrain, and the local habitat. But it is a city with all its specializations, diversity, and commerce.
They mention an ecovillage near Vancouver that I've never heard of: Jericho Hill Village, apparently near Walnut Grove. It's about fifty km from the city centre, which is probably why I don't know it.
The modernist, mechanistic era appears to be ending in most areas of human endeavor as postmodern critiques destroy the assumptions that it is built on:
But the lineage of importance in this chapter is the one that has fought for the organic city in modern times—that is, those who opposed mechanical values, who saw the human and ecological city as being squeezed out and replaced by dehumanized and artificial city values. This lineage can be traced through a number of writers and activists—for example, through John Ruskin (1819-1900), William Morris (1834-1896), Ebenezer Howard (1850-1928), Patrick Geddes (1854-1932), Lewis Mumford (1895-1990). There are many contributors in each generation. Our own includes Jane Jacobs [20,21,22,23], Ian McHarg , Ken Schneider , Christopher Alexander [1,2], Michael Hough , and Roberta Gratz . The writings of these people contain a common thread of organic thinking stressing diversity, human scale, heritage, nature, community, and artistic expression.
The biggest force still driving the Auto City to build large freeways and accommodate the automobile rather than providing other options is the standard "black box" transportation/land use model for calculating benefit-cost ratios on road projects. These are based on how a new or widened road will save time, reduce fuel, and lower emissions and road accidents. As pointed out in Chapter 3 and elsewhere, these benefits are illusory due primarily to "induced traffic."
They describe Gilbert White, E.F. Schumacher and Jane Jacobs as examples of thinkers working within the Western cultural/spiritual traditions but thinking about sustainability in cities. Schumacher, an economist by training confronted environmental problems head on, and looked into Asian development problems. He retreated to a Buddhist monastery and rediscovered Catholic faith there, and then went on to work with women in developing countries. Apparently, some of his insight "led directly to the forming of the Brundtland Commission and the concept of sustainable development."
Modern civilization and modern cities are considered by most ethical commentators to be about new ways of individualistic consumption. Postmodernism begins to question many of the certainties of this era, but it does not question this fundamental value of individualistic consumption. And yet this value by itself can become most clearly akin to the city of death, the Babylon value of arrogance and self-orientation leading to frivolous consumption. Martin Pawley [...] describes this value as privatism, or isolationism, and says that it is central to understanding our society and our cities:
Western society is on the brink of collapse not into crime, violence, madness or redeeming revolution, as many would believe—but into withdrawal. Withdrawal from the whole system of values and obligations that has historically been the basis of public, community and family life. Western societies are collapsing not from an assault on their most cherished values, but from a voluntary, almost enthusiastic abandonment of them by people who are learning to live private lives of an unprecedented completeness with the aid of the momentum of a technology which is evolving more and more into a pattern of socially atomizing appliances [40, page 75]
The automobile is the key appliance or technology for creating a private future, but it requires the city to be built around privatism for it to be seen in its fullest form. Thus in many cities it becomes difficult to do other than lead highly isolated or private lives, moving from a private, isolated, suburban home, complete with electronic entertainment (and now even electronic shopping and electronic work), to a private metal box for transportation to whatever other element of urban life one chooses. There need be no obligation to community and the city (the streets, parks, squares, public transportation, public buildings), its urban commons, can become neglected and begin to fall apart. Fear of public spaces then begins to dominate a city, particularly if inequity feeds crime in the streets.
They go on to describe communitarianism as an alternative:
The major philosophical foundation is set out by MacIntyre , Bellah [4,3], Sennett , Lasch , and Jordan .