Automobile dependence is defined as a series of convergent land use and transportation conditions in a city that leave people with few non-car options for urban travel. This dependence is compromising the environmental, social and economic health of cities in Canada. Furthermore, it appears as though automobile dependence is increasing in Canada, as are its attendant impacts. A fuller understanding of the primary relationships affecting this trend is needed if its impacts are to be adequately mitigated. However, there is little quantitative knowledge of the relative importance of factors contributing to automobile dependence in Canadian cities. A review of the literature identifies a multitude of mutually reinforcing factors that contribute to the creation of automobile dependent cities. The factors are both cause and effect and exhibit 'feedback,' which results in a cycle of intensification of the original condition. While there are many feedback relationships that contribute to automobile dependence, some may be stronger than others. Mitigating the many adverse impacts of automobile dependence requires reducing the need for both automobile ownership and automobile use by reversing these feedback relationships. This thesis identifies the relative importance of factors influencing automobile dependence in Canada's major cities through a comparative analysis of transportation, land use and population and employment distribution trends and patterns. This involves the collection and analysis of an extensive set of data from Canada's seven largest cities (Vancouver, Calgary, Edmonton, Winnipeg, Toronto, Ottawa-Hull and Montreal). To provide context and supplementary information, selected data from thirty-four additional global cities are also used. A correlation analysis of the data collected identifies the strength of correlation between factors involved in automobile dependence feedback. The data reveal commonalities between cities: those cities with higher urban densities, higher transit service provision and lower automobile infrastructure provision exhibit lower levels of car ownership and use as well as higher levels of transit use. These cities also have better utilized transit systems, have higher walking and cycling mode shares and consume less fuel. The quantitative findings are used in tandem with the qualitative findings of the literature review to identify and rank eight possible points for policy intervention in changing auto dependence feedback. Of the factors examined, metropolitan and outer area density, transit supply and CBD parking supply appear to exert the strongest relative influence on auto dependence. These are followed in importance by inner area density and car ownership, which are followed by road supply and non-motorized transport share. While the auto dependence factors ranked require further study, clarification and confirmation, they provide a preliminary basis for directing policy analysis. A policy evaluation framework is developed that enables policies prescribed in each intervention area to be assessed against a series of travel, environmental, social and economic impact criteria as well as their implementation potential. This framework can be used by policymakers to identify high leverage policies for reducing auto dependence.

Automobile dependence is defined as a series of convergent land use and transportation conditions in a city that leave people with few non-car options for urban travel. This dependence is compromising the environmental, social and economic health of cities in Canada. Furthermore, it appears as though automobile dependence is increasing in Canada, as are its attendant impacts. A fuller understanding of the primary relationships affecting this trend is needed if its impacts are to be adequately mitigated. However, there is little quantitative knowledge of the relative importance of factors contributing to automobile dependence in Canadian cities. A review of the literature identifies a multitude of mutually reinforcing factors that contribute to the creation of automobile dependent cities. The factors are both cause and effect and exhibit 'feedback,' which results in a cycle of intensification of the original condition. While there are many feedback relationships that contribute to automobile dependence, some may be stronger than others. Mitigating the many adverse impacts of automobile dependence requires reducing the need for both automobile ownership and automobile use by reversing these feedback relationships. This thesis identifies the relative importance of factors influencing automobile dependence in Canada's major cities through a comparative analysis of transportation, land use and population and employment distribution trends and patterns. This involves the collection and analysis of an extensive set of data from Canada's seven largest cities (Vancouver, Calgary, Edmonton, Winnipeg, Toronto, Ottawa-Hull and Montreal). To provide context and supplementary information, selected data from thirty-four additional global cities are also used. A correlation analysis of the data collected identifies the strength of correlation between factors involved in automobile dependence feedback. The data reveal commonalities between cities: those cities with higher urban densities, higher transit service provision and lower automobile infrastructure provision exhibit lower levels of car ownership and use as well as higher levels of transit use. These cities also have better utilized transit systems, have higher walking and cycling mode shares and consume less fuel. The quantitative findings are used in tandem with the qualitative findings of the literature review to identify and rank eight possible points for policy intervention in changing auto dependence feedback. Of the factors examined, metropolitan and outer area density, transit supply and CBD parking supply appear to exert the strongest relative influence on auto dependence. These are followed in importance by inner area density and car ownership, which are followed by road supply and non-motorized transport share. While the auto dependence factors ranked require further study, clarification and confirmation, they provide a preliminary basis for directing policy analysis. A policy evaluation framework is developed that enables policies prescribed in each intervention area to be assessed against a series of travel, environmental, social and economic impact criteria as well as their implementation potential. This framework can be used by policymakers to identify high leverage policies for reducing auto dependence. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning

published_or_final_version / Transport Policy and Planning / Master / Master of Arts

This study examined the consequences of the opening and operation of a new highway north of Richmond, Virginia with respect to contamination of the aquatic environment with heavy metals (Zn, Cd, and Pb), and the effects of these metals on the biota of roadside streams. Sixteen sites located on six small, soft-water streams that were crossed by the highway, encompassing six reference sites located upstream of the highway, six sites located directly at the highway, and four sites located downstream of the highway, were sampled over a two and a half year period, allowing both spatial and temporal analyses. Traffic densities on the highway averaged about 12,000 vehicles per day (vpd). Significant increases in the metals concentrations of sediment, benthic invertebrates, fish whole-bodies, and fish tissues (liver, kidney, and bone) were noted over the course of the study, although the increase varied in magnitude, and were not always consistent. Sediment metals concentrations followed a dynamic plateau. Fish whole-body concentrations of Cd and Pb increased steadily over the course of the study. Spot-sampling for the same parameters along another nearby, more heavily traveled highway (50,000 vpd) indicated that increases in metals concentrations in the different ecosystem components at the study streams would have been greater had there been more traffic. A number of biotic parameters were investigated to determine whether metals contamination was affecting the biological integrity of the study sites. These were: benthic macroinvertebrate diversity and density; the percentage of the aquatic insect community that was composed of chironomids; and fish community diversity, density, and biomass. Only benthos density, the percent chironomids, and fish species diversity showed changes that could be related to metals contamination. Indications from spot sampling along the more heavily traveled highway were that if more contamination had been experienced, more biotic parameters would have been disturbed, and to a larger extent. Fish community structure analyses using the Pinkham-Pearson coefficient of similarity indicated that fish community structure became increasingly altered at highway sites, and to a lesser degree downstream sites, over the study period. / Ph. D. / incomplete_metadata

[Truncated abstract] Air pollution is increasingly perceived to be a serious intangible threat to humanity, with air quality continuing to deteriorate in most urban areas. The main sources of inner city pollution are motor vehicles, which generate emissions from the tail pipe as well as by evaporation. These contain toxic gaseous components which have adverse health effects. The major components are carbon monoxide (CO), nitrogen dioxide (NO2), nitric oxide (NO), sulphur dioxide (SO2), particulates (PM10), and volatile organic compounds (VOC). CO and oxides of nitrogen (NOx) are major emissions from cars. This study focuses on pollutant concentration in Perth city and has sought to develop measures to improve air quality. To estimate concentrations, the study develops air pollution models for CO and NOx; on the basis of the model estimates, effective policy is devised to improve the air quality by managing travel to the city. Two peaks, due to traffic, are observed in hourly CO and NOx concentrations. Unlike traffic, however, the morning peak does not reach the level of the afternoon peak. The reasons for this divergence are assessed and quantified. Separate causal models of hourly concentrations of CO and NOx explain their fluctuations accurately. They take account of the complex effects of the urban street canyon and winds in the city. The angle of incidence of the wind has significant impact on pollution level; a wind flow from the south-west increases pollution and wind from the north-east decreases it. The models have been shown to be equivalent to engineering and scientific models in estimating emission rate in the context of street canyons. However the study models are much more precise in the Perth context. ... The models are used to calculate the marginal effects for all attributes and elasticity for fuel price. In almost all attributes the non-work group is more responsive than the work group. Finally, the SP model results are integrated into an econometric model for the purpose of prediction. The travel behaviour prediction is used to estimate the policy impact on air quality. The benefit from the air quality improvement is reported in terms of life saved. The estimated relationships between probability of death and air pollution determines the number of lives that could be saved under various policy scenarios. A ratio of benefits to the financial and perceived sacrifices by drivers is calculated to compare the effectiveness of the suggested policies. A car size charge policy was found to be the most cost effective measure to ameliorate the environmental impact of cars in Perth, with a morning peak entry time charge being almost as cost effective. The study demonstrates the need for appropriate modelling of air pollution and travel behaviour. It brings together analytical methods at three levels of causality, vehicle to air pollution, charge to travel response, and air pollution to health.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management