(Ed Note: Most of the information on Bicycle Friendly Street treatments in this post comes from the new Bike Plan’s Technical Design Handbook. Though we are happy to present it in bite-sized pieces, we highly recommend you download it yourself and have a good read. You can download the Technical Design Handbook here. For a refresher on what a Bicycle Friendly Street is – you can read our introductory post here.)
In our ongoing series explaining the elements of a Bicycle Friendly Street, today we will laud the virtues of the Mini Roundabout. The mini-roundabout is related to the traffic circle, which was conceived in 1902 by William Phelps Eno (the “Father of Traffic Safety” and designer of Columbia Circle). The terms tend to get lumped together often and can lead to some confusion. However, in a roundabout:
- Yield Control is used at all entries (no stop signs).
- Circulating vehicles have the right-of-way.
- Pedestrian access is allowed only at the legs of the roundabout, behind the yield line.
- All vehicles circulate counter-clockwise and pass to the right of the central island.
- Deflection is built into the design in order to slow down motor vehicles upon entry into the roundabout.
The roundabouts being described in this post have a single lane surrounding a raised island in the center of an intersection (they can also be multi-lane). They range in price from $100,000 to $750,000 for installation and are considered to be a Level 5 treatment, which is the highest level of treatment provided for in the 2010 LA Bike Plan‘s Technical Design Handbook (TDH). Read more