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Interchanges   Access Management   Single Point Urban Interchange   Roundabout


While not an interchange design, roundabouts can be used at intersections located near an interchange to help increase safety and keep traffic moving.

A roundabout is a way to get large volumes of traffic through an intersection quicker, safer and more economically. Used in many foreign countries, the one-way circular intersection channels traffic around a central island without the use of traffic signals. Drivers slow down as they approach the roundabout and yield to the traffic already circulating. Drivers then enter to the right when a gap opens, keeping the free-flowing movement going. By yielding instead of stopping at a signal, motorists can be on their way quicker.

Roundabouts add to driving safety by reducing a signalized intersection’s 22 conflict points (spots where vehicles could collide) to eight. The fewer conflict points, combined with slower speeds and calmer traffic, can translate into fewer – and less severe – crashes. Roundabouts help lower costs by reducing driver delay, which saves time and fuel, and reduces pollution. The state also benefits by eliminating about $5,000 per year in maintenance of signals and electricity costs.



Roundabout 3D animation photo match
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(4.7MB / 4.2MB)
You will need QuickTime (QT) or Windows Media Player (WM) to view the video.




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