It seems like a logical conclusion that if your streets are clogged, you need more lanes for cars. But, in a curious phenomenon known to urban planners, cars seem to fill whatever space they're given.
What many cities have found is the opposite. Build bike lanes, sidewalks and better public transportation, throw in a few trees lining the streets for good measure, and traffic often slackens. The traffic that does flow through flows in a more orderly, safe fashion.
Strategies for reducing congestion -- like HOV lanes, bike and walking lanes and other traffic calming features like narrow lanes increase traffic congestion by some measures typically used by planners, but reduce per capita delay because "they reduce total vehicle mileage and allow traffic to flow more smoothly," according to the Victoria Transport Policy Institute.
Other studies have found similarly mixed results. It's a mantra of the new urbanist design paradigm, one that is increasingly being considered in "smart growth" strategies across the country designed to combat sprawl by investing in existing cities and villages. At its heart, it isn't about transportation -- it's about people, and creating great communities where people can live, work and play.
But isn't that the kicker? Transportation isn't really about cars in the first place.
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