Cycling Safety in Roundabouts and Diverging Diamond Interchanges
March is Florida Bicycle Month, and more and more Floridians are pushing their bikes out into the sunshine. Nearly 25 million residents and tourists participate in bicycling in Florida annually, so the Florida Department of Transportation (FDOT) utilizes various roadway features to provide additional safety benefits for both motorists and cyclists. Among these features are roundabouts and diverging diamond interchanges.
Roundabouts
A roundabout is a one-way, circular intersection that uses signs to guide motorists in a counterclockwise motion around a center island. Entering traffic must yield to the circulating traffic already within the roundabout.
Here are some things to keep in mind when approaching a roundabout on a bicycle:
- If you’re uncomfortable with riding a bike alongside vehicle traffic, simply walk your bike at a marked crosswalk.
- If you’re walking your bike at the crosswalks, yield right-of-way to pedestrians. Wait at splitter islands (small, usually raised median islands), if needed while crossing.
- When cycling with traffic, follow the same rules as motor vehicles and use hand signals to indicate direction.
Roundabouts ensure vehicles pass through at slower speeds and face fewer conflict points than at traditional intersections. A conflict point is where road users cross paths as they travel through or turn from one route to another. Conflict points are always present at intersections. Limiting the number of conflict points at an intersection not only reduces the frequency and severity of crashes, but also improves the overall operation and mobility.
For more information on the benefits of roundabouts, please visit fdot.tips/roundabout.
Diverging Diamond Interchanges (DDIs)
A DDI is an innovative interchange that crosses traffic over to the opposite side of the roadway. This reduces the number of traffic signal phases and allows drivers to make a left turn without crossing in front of oncoming traffic. The lanes then change back to the right side of the road, once past the interchange.
Central Florida’s first DDI opened at Interstate 95 (I-95) and Viera Boulevard in July 2019. More DDIs are planned along the Interstate 4 (I-4) corridor at County Road (C.R.) 532 near ChampionsGate, Daryl Carter Parkway, and Sand Lake Road (State Road 482).
Here are some things to keep in mind when approaching a DDI on a bicycle:
- If you’re uncomfortable with riding alongside vehicle traffic in the designated bicycle lane, simply walk your bike through the interchange on the pedestrian walkways.
- When riding alongside traffic, remain in the bicycle lane by following the pavement markings.
- When automobile traffic shifts to the opposite side of the road, cyclists will be on the inside rather than the outside. The bike lane will shift back to the outside on the far side of the interchange when traffic returns to the right side of the roadway.
Like roundabouts, DDIs are designed to reduce the number of conflict points compared to a conventional diamond interchange. Fewer conflict points provide safety benefits for motorists as well as pedestrians and bicyclists.
For more information on the benefits of DDIs, please visit I4Beyond.com/DDI.
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