Roundabouts are one-way, circular intersections designed to improve safety and efficiency for motorists, bicyclists and pedestrians. In a roundabout, traffic flows through a center island counterclockwise. A roundabout redirects some of the conflicting traffic, such as left turns, which cause crashes at traditional intersections. This is because drivers enter and exit the roundabout through a series of right-hand turns.

A well-designed roundabout can improve safety, operations and aesthetics of an intersection. Greater safety is achieved primarily by slower speeds and the elimination of more severe crashes and operation is improved by smooth-flowing traffic with less stop-and-go than a signalized intersection. Aesthetics are enhanced by the opportunity for more landscaping and less pavement.

Over the past few years, DOTD has constructed roundabouts across Louisiana in an effort to increase safety and traffic flow at select locations.

For general information on roundabouts including photos and videos, visit the DOTD Roundabouts Project Page.

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Brochures and Engineering Documents

Signing and Pavement Marking Standards.aspxSigning and Pavement Marking Standards6/24/2015 8:38 AM2 KB
Roundabout NCHRP Report .aspxRoundabout NCHRP Report 12/14/2013 5:34 PM2 KB
Buses and Fire Trucks Traveling Through a Roundabout.wmvBuses and Fire Trucks Traveling Through a Roundabout9/3/2014 8:20 AM21921 KB
Roundabout Info and Instructions.pdfRoundabout Info and Instructions10/9/2014 11:33 AM1479 KB
Roundabout Design in Road Design Manual, Ch 6.aspxRoundabout Design in Road Design Manual, Ch 66/24/2015 11:26 AM2 KB
US 51 roundabout video.mp4US 51 roundabout video8/31/2015 1:49 PM17365 KB
Roundabout List.pdfRoundabout List3/1/2019 3:28 PM106 KB
Roundabout Map.pdfRoundabout Map3/1/2019 3:28 PM3572 KB
EDSM VI.1.1.2 Intersection Control Evaluation (ICE) Requirements.aspxEDSM VI.1.1.2 Intersection Control Evaluation (ICE) Requirements6/30/2021 9:00 AM2 KB
DOTD Sidra Parameters.pdfDOTD Sidra Parameters4/29/2022 1:42 PM427 KB