U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
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A roundabout is a type of circular intersection, but is quite unlike a neighborhood traffic circle or large rotary. Roundabouts have been proven safer and more efficient than other types of circular intersections.
Figure 1. Modern Roundabout Schematic
Roundabouts have certain essential distinguishing features:
FHWA identified roundabouts as a Proven Safety Countermeasure because of their ability to substantially reduce the types of crashes that result in injury or loss of life. Roundabouts are designed to improve safety for all users, including pedestrians and bicycles. They also provide significant operational benefits compared to conventional intersections.
Roundabouts can provide lasting benefits and value to tribal communities in many ways.
Location: Bellingham, WA
Tribe: Lummi Nation
Location: Ganado, AZ
Tribe: Navajo Nation
Location: Oneida, WI
Tribe: Oneida of Wisconsin
In 2001, the Tulalip Tribes constructed a roundabout at the entrance of their newly developed Tulalip Resort Casino in Washington State. For the intersection of 34th Avenue NE and Quil Ceda Boulevard, the Tribes chose a roundabout over a traffic signal because of the immediate safety and mobility benefits, as well as lower future maintenance costs.
Though initially hesitant, as they learned more the Tribes realized roundabouts provided more advantages. The roundabout was landscaped with features that reflected tribal heritage using colors, materials and other elements. The roundabout now serves as the grand entrance to the development. For the Tulalip Tribes, the roundabout is a safer, cost–effective, more visually appealing alternative to a traffic signal.
For more information, please contact:
Economic Development Project Manager
Successfully delivering a roundabout project requires coordination with all stakeholders. This naturally includes the road authorities involved, but efforts should also be made to seek input from other public safety providers (i.e., police, fire, EMS) and members of the community. Open communication can help clarify goals and expectations, and provide feedback that shapes the roundabout design for the better, ultimately ensuring that the final project can appropriately serve its users — from large trucks moving freight to children walking to school.
Like any intersection, a roundabout can sometimes be jointly owned by multiple units of government, such as a tribe and county. This makes building partnerships between all stakeholders a necessity. However, it also presents opportunities to pool and leverage resources, share costs, and ultimately lead to a project becoming a reality sooner than would otherwise be possible. The cost to construct a roundabout varies based on many factors, but is often a cost beneficial alternative to traffic signals.
Jeffrey Shaw, P.E., PTOE, PTP
FHWA Office of Safety
708.283.3524 or firstname.lastname@example.org
Hillary Isebrands, P.E., PhD
FHWA Resource Center
720.963.3222 or email@example.com
FHWA Tribal Transportation Program
360.619.7751 or firstname.lastname@example.org
To learn more about roundabouts, please visit:
1 AASHTO, Highway Safety Manual (Washington, DC: AASTHO, 2010)