Proximity Trumps Mobility: Smart Growth Maximizes Accessibility

The increased proximity provided by more compact and centralized development is about ten times more influential than vehicle traffic speed on the number of destinations that people can reach within a given travel time.

1 minute read

December 26, 2012, 11:00 AM PST

By Todd Litman


Researchers analyzed the number of destinations that can be accessed within a given amount of travel time by mode (automobile and transit) and purpose (work and non-work trips) for about 30 US metropolitan areas. They found that although denser urban development tends to reduce vehicle travel speeds, the increased proximity is about ten times more influential than travel speed in determining a metropolitan area’s overall accessibility. This indicates that smart growth policies which increase development density and mix, transport network connectivity, and transport system diversity can do more to improve overall transport system performance than efforts to increase traffic speeds and reduce congestion. 

The authors conclude, "Having destinations nearby, as when densities are high, offers benefits even when the associated congestion slows traffic. Where land use policy frequently seeks to support low-development densities in part in an attempt to maintain travel speeds and forestall traffic congestion, our findings suggest that compact development can often improve transportation outcomes."

Thursday, May 3, 2012 in Journal Of The American Planning Association

"Planetizen federal action tracker" logo superimposed over black and white image of US Capitol dome.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

October 28, 2026 - Zachary Whalen

A car drives through a puddle, making a large splash. Rain pours down.

California plans to bury El Niño’s downpour

If the state plays its cards right, it may be able to store a billion acre-feet of El Niño’s water in aquifers.

October 28, 2026 - Grist

Lake Powell with much of the water evaporated.

Desperate measures: Advocates weigh draining Lake Powell to fill Colorado River

Draining the reservoir could reduce evaporation losses by a couple hundred thousand acre-feet.

October 30, 2026 - Yale Environment 360

Mamdani behind a microphone, in front of a snowbank

Mamdani’s pied-à-terre tax survives legal challenge

A panel of judges found that the plaintiffs failed to demonstrate injury as a result of New York City's implementation of the tax.

November 6 - CNN

A road in north eastern Nebraska with power lines on either side, and grassy fields.

Eastern Nebraska is running out of electricity

Data centers and electrification are straining eastern Nebraska’s grid, throttling economic development.

November 6 - Grist

People board a bus in Seattle.

Seattle passes record-breaking transit services expansion

Proposition 1 will double the city’s transit tax to add 95,000 more bus trips and preserve 180,000 bus trips annually.

November 6 - KOMO News

FREE Course: Walkable City 1: Why Walkability?

After describing his path towards focusing on walkability as the essence of good planning, Jeff Speck marches through his five principal reasons for making more walkable places.

Reinventing Malls: Planning Alchemy—Turning Gray Fields Into Gold

The course focuses on the opportunities and imperatives that shape reinvention of mall sites.