Portland pursues the ‘20-minute neighborhood’

The Office of Sustainable Development in Portland, Oregon, has decided that one of the best ways to cut down on greenhouse-gas emissions is by fostering what it calls the “20-minute neighborhood.”
Since 1993, when Portland became the first large city in the US to adopt a plan aimed at preventing global warming, the city has made substantial progress on reducing damage to the environment, at least on a per capita basis. Carbon dioxide emissions in Portland and Multnomah County in 2007 were estimated to be slightly under those in 1990, even though the population grew by approximately 18 percent during that 17-year span. Per capita, emissions have dropped by 16.2 percent since 1990.
The improvement reflects a growing use of light-rail transit, an increase in commuting by bicycle, and the addition of housing and retail in walkable neighborhoods. It also reflects a local energy conservation ethic, the urban growth boundary, a healthy central city, and local political leadership, says Eliot Allen of Criterion Planners in Portland.
“SmartTrips,” a transportation options education and outreach program administered by the Transportation Department, has reduced single-person auto trips by 9 to 12 percent in each of five target areas since 2004, says

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