Date of Award

Spring 2013

Document Type


Degree Name

Doctor of Philosophy (PhD)


Civil/Environmental Engineering

Committee Director

Asad Khattak

Committee Member

Mecit Cetin

Committee Member

Man Wo Ng


The purpose of this dissertation is to discover the VMT impact of each level of proximity in order to help government identify key locations for housing development, and thereby lower VMT and reduce dependence on foreign oil. By discovering the VMT impact of each level of proximity, this dissertation provides a) the first known means of calculating the proximity-based VMT benefit of subject locations by individual proximity level, and b) the new finding that it is likely that high VMT benefit can be achieved at moderate proximity levels acceptable to many households, enabling representative governments to be politically successful while promoting housing in locations that will lower the average VMT of the population.

After discussing the impetus for the work, this dissertation presents a theory of the determinants of VMT, searches the literature for appropriate techniques for empirical analysis of the proximity-VMT relationship, and presents results of the empirical research to be expected based on the presented theory and literature.

Empirical efforts are used to discover VMT impact by proximity level using three differing measures of proximity: density, distance-threshold-based total opportunities, and centrality. In the first effort, national data is used to discover VMT impact by proximity level, for both population and employment density. In order to determine the role played by alternative modes in the VMT-density curves of the first effort, the second effort uses national data to discover the impact of each level of density on usage of alternative modes. In the third and final effort, data from Hampton Roads, Virginia, are used to discover the VMT impact of each level of opportunity and centrality.

Governments can apply the discovered VMT impact of each level of proximity--via a described "VMT Benefit Technique"--to accurately determine the VMT benefit of a given location, and use the VMT benefits of a set of candidate areas to select key locations for development.

In addition, the discovered VMT impact of each level of proximity informs the key hypothesis of this dissertation that there exists a sweet spot on the VMT-proximity curve that has high VMT benefit and a proximity level acceptable to many households. Although the hypothesis tests indicate that it is not certain that the sweet spot exists, the mean coefficients of the models indicate that it is likelythat the sweet spot exists, i.e. that there are high-VMT-benefit proximity levels acceptable to many households. The overall implication of this is that representative governments in the U.S. who promote housing development at these moderate levels of proximity will not only lower average VMT in the short term, but they will not be punished politically for doing so, and therefore may be successful in thereby lowering average VMT in the long term.

In summary, the dissertation provides encouragement to governments hoping to lower average VMT and an accurate method of calculating VMT for choosing SGAs with which to actually lower average VMT. It is hoped that this combination will help U.S. governments become independent of foreign oil.