A way to fight app directed through traffic: cul-de-sacs

The suburbs are full of of cul-de-sacs. Homeowners might prefer them because of the quiet and the space that they allow for kids and vehicles. They can help developers and builders fit more houses into spaces.

At the same time, cul-de-sacs may be the bane of New Urbanism as neighborhoods with many of them do not have a consistent street grid and they are primarily lined by private single-family homes. One video promoting New Urbanism put it this way: The greatest threat to our planet is…

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Yet, cul-de-sacs do provide one additional advantage in today’s world. They can limit the effectiveness of Waze and other traffic or mapping apps: cars and traffic cannot cut through cul-de-sacs. I saw this argument recently in a 2001 newspaper article where a suburban leader said they had restricted commercial development to main roads and highways and the high percentage cul-de-sacs and loops among the residential roads kept neighborhoods quiet. With more cul-de-sacs, more traffic is routed to arterial roads, streets that can usually accommodate more volume. Cul-de-sacs help make residential neighborhoods harder to navigate; I can think of several residential neighborhoods in my area that make it very difficult to find your way through if you are not familiar with it because of the winding roads and dead ends.

New Urbanists would argue that this is not ideal: more cars on arterial roads is going to lead to more congestion (as opposed to a grid system that provides drivers lots of options), arterial roads may be less friendly to pedestrians and bicyclists, and we should be working to reduce driving anyhow rather than planning communities around cul-de-sacs that depend on cars.

Speed bumps, roadside speed monitors, and other devices might not be enough to stop through traffic in residential neighborhoods. Permanent cul-de-sacs could do the trick – but at a cost to the overall fabric of the neighborhood and community.

The grid is better for us than winding streets and cul-de-sacs

New Urbanists, advocates for more traditional grid street designs, would be happy to read this article that “Dubunk[s] the Cul-De-Sac.” This is a good summary of research that has been gaining attention for some years now and suggests that the now common suburban street is more harmful than the traditional grid.

While these knowledge is well-known amongst planners, I wonder how typical Americans would respond to this. How can one calculate the trade-offs in safety and alternative routes granted by the grid versus having a home on a quiet cul-de-sac where kids can play basketball, street hockey, ride bikes, and more right in front of the house?