Bernard Guichet, the French federal highway planner who presented at Vail and KC was asked the French roundabout mix--his answer was 5% three or more lanes,  20% two lanes, and 75% one lane.  Do you have some source of data on this?  More important, is a roundabout with RYG really a roundabout?

Tony Redington

Montreal 

France Vs USA

Good to see a reference link and a reminder that the TRB conference material, both 2005 and 2009, offer a lot of good material.  One of my favorite slides (Tuesday, 2009, on global safety)  States that:

France averages 1 crash per 15 RBTs per year, and 1 fatal per 500 roundabouts per year. Even our 'best' traffic signals, collectively, can't get to these low numbers.

Since the French are at 30,000 roundabouts, this really helps their national effort towards reducing total traffic crashes and fatalities. Ideally, the new US surface transportation act would fund 2,000 new roundabouts per year for the next five years. That would be a good start towards reducing the intersection related carnage on the US system. This would be a stimulus package for both short-term employment and long term public safety.

France

funded about 1,200 per year.

Safety is now all about conflict management.  We have done so much to improve road design and vehicle occupant protection - now we need to reduce conflict rate and speed differential.

Philip Demosthenes, Consultant

Principal Planner

Denver, Colorado

303-349-9497

pdemos@ecentral.com

www.pdemosthenes.com