Traditional neighborhood developments reduce VMT

A series of similar studies in recent years have compared traditional neighborhood development (TND) to conventional suburban development (CSD) and found that higher density, a mixture of uses, and better connectivity reduce vehicle miles traveled (VMT) at least 20 percent — even on greenfield sites.

Residents of Southern Village, a TND in Chapel Hill, North Carolina, generate 22 percent fewer automobile trips and take three times as many walking trips as residents of nearby Northern Carrboro, a CSD area similar in size and demographics, according to a study by Khattak and Rodriguez (2005). Southern Village features a mixture of uses, a park-and-ride lot for bus transit, walkable streets, and lots 60 percent smaller, on average, compared to Northern Carrboro. In the TND, 17.2 percent of trips are by walking compared with 7.3 percent in the conventional community.

Residents of Fairview Village, a new urbanist neighborhood, own about 10 percent fewer cars per adult, drive 20 percent fewer miles per adult, and make about four times as many walking trips than residents of more conventional neighborhoods, according to Dill (2004). Residents of Fairview Village took fewer vehicle trips and more nonmotorized trips for local errands than residents of the control neighborhood. Comparing two suburban areas near Nashville, Tennessee, Allen and Benfield (2003) found that that the combination of better transportation accessibility (improved roadway connectivity and transit access) and a modest increase in land-use density reduces per capita VMT by 25 percent.