| Sustainable transportation attempts to address economic development, environmental stewardship, and social equity of current and future generations. While numerous qualitative studies have been performed on this topic there has been little quantitative research and/or implementation of sustainable transportation concepts. The main reasons for this are related to a lack of understanding of sustainable transportation and a lack of quantified performance measures. To address this problem, a comprehensive definition for sustainable transportation was developed as well as a framework on how to identify, quantify, and use performance measures for sustainable transportation in the transportation planning process. The proposed framework was applied to a test bed, comprising of two freeway corridors in Houston, Texas.; New innovations such as Automatic Vehicle Identification (AVI) data and the TRANSIMS model make it possible to obtain travel related information at highly disaggregate levels. This information can be used to quantify sustainable transportation performance measures at the individual level and levels of spatial and temporal disaggregation, that have previously not been possible. The AVI data was used to determine travel time and travel time variability for observed individual commuters. The TRANSIMS model was used to quantify mobility related performance measures at various levels of aggregation. In addition, both AVI and TRANSIMS data were used in conjunction with a number of transportation environmental impact models to quantify performance measures related to vehicular emission, noise pollution and fuel consumption at various levels of aggregation.; The performance measures that were quantified on disaggregate levels were compared to measures that were quantified with traditional aggregate data sets. It was found that the traditional approach is much less accurate due to a loss of detail and the effect of aggregation bias. Finally, it was illustrated that the performance measures based on disaggregate data can potentially provide different results as compared to aggregate approaches, when used with decision-making techniques. It was demonstrated that the disaggregate approach can be used to allocate responsibility for negative externalities, and to assess the sustainability as experienced by different user groups. It is, therefore, proposed that sustainable transportation performance measures should be quantified at a disaggregate level. |
