UBC Theses and Dissertations
UBC Theses and Dissertations
A minimal community impact urban freeway Marshall, David Stanley
From several points of view, freeways are a desirable urban technology. Not only do they provide high levels of mobility and traffic capacity, but their safety, fuel consumption and pollution-generation characteristics are the best available. Even in terms of noise generation and its impact on the urban environment, it is desirable to have maximum traffic diversion from surface streets to appropriately designed freeway facilities. Yet freeway development is not without its costs. Opposition has grown, and now assumes a dominant position, politically, throughout much of North America, because the construction of freeways has often entailed severe disruptions of settled communities. These disruptions are referred to collectively as "community impact". The problem of this paper is the design and performance evaluation of a limited form of freeway, a form which attempts to minimize community impact. To the extent that such a form is possible, the environmental and other advantages of continuous-flow operation of motor vehicles will be available at lower social cost. The study begins by identifying the impacts to be avoided. "Residential displacement", "visual intrusion", JL'noise impact" and "traffic focal points and 'dumping' of traffic" are potential impacts of freeway construction and operation. Because of the nature of the designs being considered, "difficulties of local access and parking" is included for examination, as is the satisfactoriness of the highway driving environment. The general conclusions of the study are as follows. (1) Residential displacement would be limited to the removal of one house on the 3»2 mile test route. (2) The highway would not be visually intrusive since it would be completely hidden from view. (3) At maximum noise generation, one of the test designs would produce no impact at nearby buildings and from "marginal" to "definite" impact at sidewalks adjacent to the facility; the other design would produce a "marginal" impact at the building facade and a "definite" impact at the sidewalk, (k) There would be no dumping of traffic in the study area. (The facility performs only the line-haul function with no collector/distributor element.) (5) Local access and parking could be assured, but would require the upgrading of rear lanes the parking of vehicles on private property. (6) The visual quality of the highway driving environment, though less than ideal, is judged to be satisfactory. Unfortunately the less effective of the designs from a noise containment point of view is probably the most desirable aesthetically. (7) Total development cost of each of the "minimal impact" designs approximates the total dollar costs of conventional inner-city freeways. It is concluded that minimal impact freeways appear to be feasible, both technically and economically, for the line-haul function across inner suburbs. Since it now appears possible to construct limited forms of freeway with little adverse community effect, freeways should no longer be considered a non-option for built-up-areas.
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