Filtering Permeability With Traffic Diverters

Traffic diverters can be designed as a hybrid of permeable greenways and woonerfs to make walking and biking easier, safer, and even more pleasant than driving.

2 minute read

May 11, 2014, 9:00 AM PDT

By Helen Brown


Blogger Shaun Jacobsen celebrates the unintended benefits of a one-way street that has been closed to traffic due to construction: "With so little car traffic, people feel fine crossing wherever they want, or diagonally at intersections. It’s positively pleasant to ride a bicycle…because there’s so little cut-through car traffic."

Though the resulting pedestrian- and bicycle-friendliness, or what Jacobsen refers to as "filtered permeability," is an unintentional result of road construction on his one-way street, Jacobsen recognizes that other streets could benefit by intentionally placing "car traffic diverters": "The best part about making it harder for thru car traffic is that it still permits local traffic to get where it needs to go; longer trips are diverted to arterial roads, keeping drivers off of residential streets, opening them up to people (including families with children) who want to bike safely to the store, the park, and so on...it’s a way to make it easier to make those one- or two-mile trips by a way other than driving there."

To formalize this pedestrian- and bicycle-prioritized flow, Jacobsen recommends, "it should be policy to bring the entire street to the level of the curb and introduce permeable pavement/bioswales for stormwater management, making the street a sort of greenway-woonerf hybrid." He provides a diagram to illustrate his point and notes, "This solution isn’t one designed to get people riding bikes or walking long distances, like to work downtown, but it’s a way to make it easier to make those one- or two-mile trips by a way other than driving there."

Tuesday, May 6, 2014 in Transitized

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