These efforts typically begin implementation with major new "mass" transit investments, often light-rail systems, that are designed to link central city cores, suburban downtowns, and other major activity centers. TOD is possible without new transit, but most metro areas choose to make the transit investment. Bernick and Cervero (1996) suggest that what is needed for TOD to succeed is a "transit metropolis," meaning a sufficient number of TODs having balanced or special uses that are connected and allow for efficient rail travel with bi-directional travel flows.
Construction of the new transit system usually precedes the land use restructuring required to effectively support the investment, i.e., the concentrations of population, employment, public amenities, and commercial activities that will attract transit riders in sufficient numbers to satisfy the transit system’s fare box recovery requirements. Commercial activities, in particular, often become a consideration after the transit system alignment is finalized and station areas are identified.
A useful review of previous studies in the urban planning and transportation literature of the transportation impacts of neo-traditional development and TOD is provided by Berman (1996). This paper summarizes several more recent empirical and modeling studies of TOD, and it indicates how TOD success should be measured. Specifically, it outlines the key factors that need to be understood and weighed before significant new transit investments are made. Our aim is to enhance the regional plan
