In his Play safe Op-ed, Steve Lindbeck cited a study done by the Insurance Institute for Highway Safety. The study compiled data from eight states that have built roundabouts.

The Institute examined 24 intersections in eight states that were converted from stop signs or traffic signals between 1992 and 1997. The results:

• Vehicular accidents overall declined 39 percent.
• Accidents resulting in injuries fell 76 percent.
• Accidents resulting in death or incapacitating injury plunged 90 percent.

The eight states? California, Colorado, Florida, Kansas, Maine, Maryland, South Carolina, and Vermont.



Here is a picture of one in Gainesville, Florida.

Lindbeck states that Everything you need to know to navigate a traffic roundabout you learned in kindergarten. Take turns. Be careful. Follow the rules. Do your part. Play well with others.

What Lindbeck does not tell you is a modern roundabout, according to the Institute, is a circle “designed for very low traffic speeds, about 15 mph.”

The Institute said roundabouts are not appropriate for high-volume urban intersections. And those that are in a high volume traffic intersections, they have not been built in states that have the weather and ice problems Alaska or for that matter, Anchorage has.

An example of the statistics of a high volume traffic intersection can be found in Maryland.

Maryland has also constructed three 2-lane roundabouts. One of these, the Towson roundabout, merits specific discussion. The Towson roundabout is located in a highly urbanized setting and replaced two adjacent signalized intersections. It is oval in design, having an outer diameter that varies from 140 feet to 260 feet. It involves five major approaches. At the time of conversion, the total entering volume at the existing intersection averaged nearly 50,000 vehicles per day. Since its opening, the Towson roundabout has experienced a nearly fourfold increase in annual property damage accident (2.6/yr vs 10.0/yr). However, offsetting this increase, injury accidents have decreased by two-thirds (4.2/yr vs 1.5/yr). No fatal crash occurred in either the before or after period. Incidentally, construction of the roundabout substantially improved the Level of Service (LOS) and decreased the traffic delay at the location. The morning LOS went from B to A and evening LOS improved from E to B. total vehicle delay was lowered by 70% and 58% in the morning and evening peak hours, respectively.

Property damage has increased fourfold. In other words, car accidents have increased fourfold.

Lindbeck asks, Anybody have a problem with that?

Ahhh, yeah Steve I do.

Study demonstrates roundabouts’ safety

Maryland Roundabout Safety Experience