17 minimized within the complex of 17 variables used by in certain occasions by the old multiple apartment the model. Interestingly enough, the most important buildings variable. variable in many cases is the age of the household. Unfortunately, the age of the housing units is not a COMMENTS AND REFLECTIONS policy variable. In fact, it is only a substitute variable denoting, most probably, the manner in which apart­ This paper has particular significance for both trans­ ment buildings and other housing units were designed portation and land use planners. It presents an in­ before 1940. A final point in this connection is that the novative, intensive effort to develop new, predictive, model, as it is presented in the paper, does not always and explanatory models for automobile ownership and present results consistent with a priori presumptions. modal choice. At the same time it explores in more For instance, the households in apartment buildings depth the link between the transportation planner and built before 1940 whose workers are employed in cen­ the city planner. Although the title and some of the tral business districts (CBDs) have a lower probability claims of the paper might be considered as somewhat for not owning an automobile than does a similar house­ unwarranted overstatements, the link between cha1- hold in the rest of the region-the opposite of what acteristics of the urban structure and the consumer· would normally be expected for Phoenix and Boston in patterns of urban residents is placed under central 1970. focus in the automobile ownership model. A similar Turning to the modal split model for home to work link between urban structure and travel behavior cen­ trips, the main strong points of this model are two. tered on the most important component of urban travel, First is the separation into two steps and the emphasis the home-to-work trip, is also attempted. What strikes placed on the three sociodemographic variables (in­ me also as very important in these models is the two­ come, age, size of household) plus the automobile step structure of the models and that the influence of the ownership variable. In emphasizing the intrinsic intrinsic characteristics of the household on automobile significance of these variables for modal split, the model ownership and modal choice is emphasized first on a again offers, as in the case of automobile ownership, national scale, followed by the influence that some a distinct contribution. The second strong point of the specific characteristics of each urban structure exert modal choice model is the additional stratification of on automobile ownership and modal choice. Although the workplace. The circumstances in both the origin in my view the models are not yet ready for widespread and the destination of the trip play the major role in use, their contribution is clearly evident, especially the choice of travel mode. The level of stratification with regard to the automobile ownership model. I hope the model includes and the manner in which it incor­ that these and other researchers will continue the work porates urban pattern variables need improvement if in this field so that we may increase the hopes of the model is to add to the present array of modal split establishing the frequently claimed but almost always models. In addition, the model would need to reach elusive relationship between land use patterns and much higher levels of simulation accuracy to compete transportation. effectively with other models in the field. Finally, the policy variables (except, possibly, the rail dummy variable) appear to carry only marginal importance in the correlations produced. Again the expected prob­ Publication of this paper sponsored by Committee on Transportation ability of step one is the dominant variable, followed and Land Development. A Transit-Oriented City Edward W. Walbridge, Department of Systems Engineering, University of Illinois, Chicago Cities are designed to accommodate the automobile. A transl ·oriented moving sidewalks, bicycles, and walking. A transit­ city is one that from inception is designed for public trMsportation oriented city would be an altogether new city (or town or modes rather than the automobile. In such a city, automobile use would new town-in-town) to be built from the ground up. Travel be possible but unnecessary. The goal of a transit-oriented city is to make by automobile would be possible and, in fact, would not public transportation travel more attractive than driving so that automo· biles will be little needed or used. One possible transit-oriented city is be deliberately discouraged. However, the design goal described. From this example we see that many of the advantages of would be to make public transport.l;.tion faster, safer, current urban and suburban life-styles are attainable without automo­ cheaper, more pleasant, and more convenient than auto­ biles. The building of a transit-oriented city as an experiment is sug­ mobile transportation, so that residents would choose to gested. make most in-city trips by public modes. Public trans­ portation of such attractiveness can be achieved through the integration of land use and nonautomobile movement A transit-oriented city is designed to make automobiles technologies. little needed and little used; the movement of people is When a conflict occurs in the design of a transit­ accomplished primarily by modes other than the automo­ oriented city between the needs of automobiles (such as bile. Nonautomobile modes would include new and old close-in parking or direct nonstop routes) and the needs types of mass transit, constant speed and accelerated of nonautomobile modes, the latter are given priority, 18 Similarly, the need for a pleasant urban environment is city. Each of the square-shaped figures is a cell or predominant over that for swift and convenient automobile community, which has a transit station at its center. The travel. Except for these two priorities, automobile two round areas a1·e the central business district (CBD) transportation is not hampered or restricted by artifi­ (above) and ru1 industrial park (below). Transit guide­ cially low speed limits or by the prohibition of automo­ ways (shown as lines) link the transit stations (shown as bile use at certain times, for example. dots). Circwnferential highways and an access l1ighway Transit-oriented cities offer, in the long term, a ai·e also shown. possible solution to the problems created by urban auto­ Not shown are the local roads that thread through the mobiles. These problems include air and noise pollution; CBD and the industrial park and connect these to the accide11ts; congestion; excessive consumption of petro- · communities. The local roads are intended primarily leum energy; excessive use of urban land; and unavail­ for service and delive1·y t1·ucks. The local road system ability to the poor, aged, handicapped, and young. The requires indirect routes and is not designed for high conventional approach to these problems is to improve speeds. There is limited room for automobile parking automobiles. This approach is appropriate for the near in the industrial park and none in the CBD. Automobile term in existing automobile-dominated cities and towns. drivers destined for the CBD must park at lots on its It is the approach that is being taken in the United States, perimeter and enter by foot. Once in the CBD they can Where an effort is under way to make automobiles less move about by foot, by moving sidewalk, or by the tran­ polluting and more energy efficient. sit system. In the CBD, the second-story level is the The transit-oriented city approach is appropriate for pedestrian level, one story above ground; trucks are re­ new cities, rebuilt parts of older cities, and new towns­ stricted to ground level. People enter buildings and tran­ and it is appropriate for the long term, by which I mean sit vehicles at the pedestrian level, The moving side­ 20 years or more into the future. Transit-oriented cities walk system is on the pedestrian level and pedestrian offe.1· alternative life-styles, wl1icll are not dominated by bridges arc over the CBD's truck streets. The move­ the automobile. These nonautomobile-dominated llie­ ment of people to and from the CBD and the industrial styles may be more attractive and cheaper than the auto­ park is primarily by transit and only to a limited extent mobile-dominated life-style available in contemporary by automobile. The movement of goods to and from the cities and suburbs. Whether new life-styles can, in fact, industrial park, the CBD, and the communities is by be more attractive is especially important because of truck. diminishing petroleum supplies. Figure 2 shows a typical community. It is a picture A transit-oriented city must be designed so that of a model built by Victor Wong. The community con­ automobile-related problems will not simply be replaced sists of a central doughnut-shaped structure surrounded by other transit-related problems. A poorly designed by four groups of buildings. In the cente1· of the doughnut transit-oriented city might suffer from -people congestion is a park, and under the park is the tran_ait station. The in its transit vehicles and stations. A congested transit exterior of the doughnut structure contains townhouses system can be avoided by carefully matching transporta­ and apartments. The roof of each townhouse supports tion capacity to transportation demand. The public trans­ the yard of the townhouse just above. In Figure 2, one portation system in a transit-oriented city could be un­ can see the trees in the townhouse yards. Inside the duly costly and unduly consumptive of energy unless the doughnut is a circular mall, which has a circular moving city is designed to minimize the need for the movement sidewalk rwuung U1rough it.