Banish the Cul-de-Sac

This is the 22nd post in a series of posts this December that will chronicle the 25 things we would most like to see in Roswell. None of these are actually happening... at least in the way we'd like them to. Please enjoy and have a happy holidays!

 

This one really, badly needs to happen.  If you want to start dealing with congestion on our major roads such as Holcomb Bridge and Hwy 9, creating a more connected road network will work wonders and eliminate the perceived need for more lanes on those large roads.  So, my suggestion is that all new subdivisions should be forbidden to have cul-de-sacs and existing subdivisions should be given incentives to add themselves to the effective network.  The only acceptable reason for a cul-de-sac is due to geographic or topographic limitations.  In 2009, the state of Virginia led the way by banning cul-de-sacs in new developments.  

The modern day cul-de-sac is a necessity that, in it's modern form, was principally borne from the large lot single-use zoning methods of the 20th century.  Essentially, the zoning created superblocks and the only way to get to the center of those superblocks was to create cul-de-sacs to access the land in the middle.  So, that's exactly what developers did.  They glorified the privacy that the cul-de-sac provided and completely forgot about the connectivity that it killed.  

There are many studies out there that conclude that overall connectivity fosters: 

  • Decreases in vehicle miles traveled
  • Decreases in body mass index
  • Increases in walkability
  • Increases in bikability
  • Decreases in serious/fatal car accidents
  • Increases in emergency response times 

The City of Roswell has a limited effective network due to the fact that so many superblocks with limited connectivity were created in the suburban subdivisions and large commercial parcels permeating throughout our city.  The image below illustrates the comparison between all roads in Roswell and the effective network in Roswell. 

The effective network on the right consists of olly 44% of the total roads in the city.  The other 56% are essentially cul-de-sacs.  They stem off of an arterial or collector road and don't allow alternative entrances/exits.  

I'd like to see the cul-de-sac banned on future development and remediated where possible on existing development.  You can check out this Ga Tech study from 2006 to see some examples of how Roswell can start to repair the mess.

images: City of Roswell