Unwanted excess commuting: Proximate commuting, transportation demand management and the transportation -land use connection.

This dissertation examines the theoretical and planning implications of a proximate commuting program, which reduces commuting through voluntary employee relocations to different job sites. Data from dissagregate surveys of individuals belonging to a spatially distributed homogenous job class, bank tellers, were used to derive excess commuting estimates for two case studies: Bogata, Colombia and Southeastern Michigan. Additional data on tellers' willingness to participate in a proximate commuting program were gathered. Proximate commuting information allows for apportioning excess commuting into wanted and unwanted components. Wanted excess commuting is commuting that people have accepted as a tradeoff for having access to other desired destinations or activities. Unwanted excess commuting is wasteful travel; since it is not desired given current land use patterns, it is amenable to disappearing by enabling individuals to be relocated. Results based on optimization and Monte-Carlo techniques suggest that 18 percent and 5 percent of Bogata and Southeastern Michigan tellers' commuting is unwanted. Estimates of proximate commuting benefits for one firm in Southeastern Michigan include yearly savings of 32,400 km. The program would avoid 330 kg (2 kg per employee) of emissions stemming from consumption reduction of 950 gasoline gallons (5.6 gallons per employee) per year. These benefits, however, are a function of the number of employees, and the number of potential destinations available, among others. If 0.1 percent of the U.S. working population were eligible for proximate commuting, yearly emissions savings would reach 360 tons. These savings indicate that proximate commuting is a highly cost-effective transportation demand management program. Results suggest that the transportation and land-use relationship is not always strong enough to motivate individuals to reduce unwanted commuting independently, but that policy intervention can overcome obstacles to peoples' desires for commute reduction. Behavioral choice models of a teller's decision to participate in proximate commuting, however, suggest that accessibility improvements are the main motivation for program participation. Thus, the behavioral models' results show that individuals value improvements in accessibility, thereby underscoring the transportation land-use connection's continuing strength. That a considerable percentage of commuting for this sample can be reduced through a planning intervention highlights the potential of achieving desired accessibility enhancements.Ph.D.Social SciencesTransportationUrban planningUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/132671/2/9977248.pd