Block size, not just density, key to cutting auto travel

A study by the universities of Washington and Maryland researchers adds further weight to the notion — now confirmed in many studies — that smart growth (higher density, mixed-use, walkable urban form) significantly reduces vehicle miles traveled (VMT). The study, published in Transport and Land Use, emphasizes that reducing block sizes is a more important factor than density and mixed-use in some cases. The study looked at subareas of the Washington DC, Seattle, Baltimore, Richmond VA, and Norfolk VA metro areas. The Virginia metro areas are smaller than the others, and the subareas studied there are lower-density and more sprawling (as measured by block size). In Washington, Seattle, and Baltimore, where the urban pattern is well established, an increase in density and mixed-use had a greater effect on VMT. "Reducing the average block size turns out to be the most effective in the Virginia case with the largest existing average block size," note the authors of the study "How built environment affects travel behavior: A comparative analysis of the connections between land use and vehicle miles traveled in US cities."

For more in-depth coverage: 

• Subscribe to Better! Cities & Towns to read all of the articles (print+online) on implementation of greener, stronger, cities and towns.

• Get the December 2012 issue. Topics: Sprawl versus walkable: Housing study, Nashville code creates value, Wake up call from Sandy, Downtown Columbia, Smart growth at the polls, Buffalo code reform, Housing and driving costs, Comparing new urban and conventional development, NorthWest Crossing, Alexander's The Battle for the Life and Beauty of the Earth

• Get New Urbanism: Best Practices Guide, packed with more than 800 informative photos, plans, tables, and other illustrations, this book is the best single guide to implementing better cities and towns.