Transit Oriented Developments (TOD) are advocated as an integrated mass transit and housing solution that lessens the dependency on private vehicles, thus they may also reduce congestion, fuel consumption and pollution.
TODs are a major reason why Oahu's large developers and bankers are behind the heavy rail proposal. It presents a massive opportunity to build and finance real estate.
Unfortunately TOD's practical goals for car dependency reduction fail to materialize. Here is a prime example from Portland, the "poster child" of Light Rail advocacy and TODs.
I quote the abstract of research reported by Bruce Podobnik of the Department of Sociology at the Lewis and Clark College in Portland, Oregon dated July 15, 2009. No further comment is necessary in regard to the traffic congestion potential of TODs:
"This study examines the extent to which specific social and environmental objectives have been achieved in the new urbanist community of Orenco Station (Portland, Oregon). House-level surveys were conducted in Orenco Station, as well as a traditional suburb and two long established urban neighborhoods. Survey data reveal high levels of social interaction in the new urbanist community, as compared to the comparison neighborhoods.
"The analysis also reveals a higher level of walking, and an increase in the occasional use of mass transit, in the new urbanist community. However, the majority of residents in all four neighborhoods (including the new urbanist neighborhood) rely on single occupancy vehicles for their regular commute.
"In sum, this study shows that Orenco Station is very effective in achieving its social objectives, modestly effective in encouraging walking and the occasional use of mass transit–but not very effective in increasing primary reliance on mass transit for commuting."