Roundabouts are statically safer intersections and have fewer accident points when vehicles use the intersection.
Consider the safety reviews of roundabouts from the independent review from the Insurance Institute for Highway Safety: https://www.iihs.org/iihs/topics/t/roundabouts/qanda#roundabouts As well as the Federal Highway Administration: https://safety.fhwa.dot.gov/intersection/innovative/roundabouts/ Video: https://youtu.be/C6LoK0hxj7k
In the State of Iowa three out of the five existing roundabouts on state highways that are designed similarly to the design in the Adel Highway 169 roundabout concept. Injury crashes have been nearly eliminated, and property damage crashes reduced in 2 of the 3 intersections. (Note: On a mobile device you may need to turn your device to landscape (sideways) to view this table in full.)
| Location (year constructed) | 5 Years Before Construction | 5 Years After Construction | ||||
| All Crashes | Injury Crashes | Property Damage Only Crashes | All Crashes | Injury Crashes | Property Damage Only Crashes | |
| IA 281 at Raymond Ave, Black Hawk County (2008) | 2 | 0 | 2 | 0 | 0 | 0 |
| IA 3 at IA 187, Fayette County (2009) | 6 | 2 | 4 | 2 | 0 | 2 |
| US 30 at 10th Ave, Mount Vernon (2013) | 10 | 6 | 4 | 10 | 2 | 8 |
Updated: 02/05/19