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

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Cover CM Credits, Earn Certificates, Push Your Career Forward

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

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

June 11, 2025 - Diana Ionescu

Large crowd on street in San Francisco, California during Oktoberfest festival.

The Simple Legislative Tool Transforming Vacant Downtowns

In California, Michigan and Georgia, an easy win is bringing dollars — and delight — back to city centers.

June 2, 2025 - Robbie Silver

Rendering of Shirley Chisholm Village four-story housing development with person biking in front.

San Francisco's School District Spent $105M To Build Affordable Housing for Teachers — And That's Just the Beginning

SFUSD joins a growing list of school districts using their land holdings to address housing affordability challenges faced by their own employees.

June 8, 2025 - Fast Company

Bird's eye view of half-circle suburban street with large homes.

In More Metros Than You’d Think, Suburbs are Now More Expensive Than the City

If you're moving to the burbs to save on square footage, data shows you should think again.

1 hour ago - Investopedia

Color-coded map of labor & delivery departments and losses in United States.

The States Losing Rural Delivery Rooms at an Alarming Pace

In some states, as few as 9% of rural hospitals still deliver babies. As a result, rising pre-term births, no adequate pre-term care and "harrowing" close calls are a growing reality.

June 15 - Maine Morning Star

Street scene in Kathmandu, Nepal with yellow minibuses and other traffic.

The Small South Asian Republic Going all in on EVs

Thanks to one simple policy change less than five years ago, 65% of new cars in this Himalayan country are now electric.

June 15 - Fast Company