Rotaries are terrifying

[Chris]

How about this one?


Pijnacker, the Netherlands.

[vtk]

Looks like it was fun to draw in CAD.  I'd probably have fun driving it, too, what with the thorough lane markings.  And, you know, the traffic lights.

[wytout]

Connecticut is starting to implement rotaries more.  Living on the MA border, and spending as many of my breathing hours as possible out on the Cape, rotaries are like second nature.

They just replaced the Five corners intersection w/ a rotary in Ellington CT (JCT CT 286, 74, Skinner Rd and Windsorville Rd).  It's working too.  The traffic used to back up a quarter mile in all directions for 5 way stop signs, now there's only about 10-12 cars at rush hour waiting to enter the rotary.  This intersection was bad the way the roads were offset.  The rotary here seems much safer because it's all 1 direction traffic movement, versus criss-crossing 5 points + people turning both directions, and no one being able to figure out who's turn it was to proceed from a stop sign.

This link shows how the intersection looked before the rotary. ZOOM OUT ONE level and the map overlay is updated to a rotary, but the satellite photo is still not updated.  The Rotary was finished about 3 months ago.
http://maps.google.com/maps?q=windsorville+and+286+ellington+ct&hl=en&ll=41.867388,-72.492503&spn=0.00306,0.006968&sll=37.0625,-95.677068&sspn=52.77044,114.169922&vpsrc=6&hnear=Connecticut+286+%26+Windsorville+Rd,+Ellington,+Tolland,+Connecticut&t=h&z=18

[empirestate]

So those of you from New England: are people still using the term "rotary" to refer to that new style of circle that everyone is building these days (the "modern roundabout")? Or is the word typically reserved for those large old circles that are so terrifying around Concord?

[hbelkins]

Here in Hartford County, Connecticut, the only one I'm aware of is at the west end of the Whitehead-Conlon Highway in Hartford. The Brattleboro, VT rotary was mentioned. That's at the junction of US Route 5/VT Route 9 and I-91's Exit 3 on/off ramp. The west side takes you to I-91, while the east side take you a whole 1/3 mile onto VT Route 9 east and the New Hampshire state line (Seabees Memorial Bridge over the Connecticut River). There's also a rotary under I-91 at Exit 26 in Greenfield, MA for MA Route 2A East and MA Route 2 West (MA Route 2 East is concurrent from this rotary north along I-91 to Exit 27).

I am pretty sure that I encountered a roundabout under construction somewhere on VT 15 back in the fall. I think it was at the VT 100 intersection near Hyde Park.

[on_wisconsin]

How about this one?
[image]

I might be an odd one but Turbo roundabouts make a lot of sense to me. Bring 'em stateside!

[Duke87]

Roundabouts are great if used in the correct circumstance. They only become deathtraps if traffic volumes are too high, causing an excessive amount of conflicts and need to yield. If traffic through the intersection is reasonably low, they're great because they allow traffic to freely flow.

The real sniff test is, with what frequency will a driver approaching the circle need to come to a near or complete stop before entering? If the intersection is good for a roundabout that should be the less common case, i.e. there should typically be more spaces to slip into than cars to dodge.

Also, if it has to be signalized, the entire purpose is defeated.

[relaxok]

I like roundabouts, as long as they're properly marked following MUTCD Chapter 3C.  I was driving in Massachusetts in '10 and came upon a roundabout somewhere on Route 2 that I found rather hair-raising.  I'm pretty sure it's a multilane roundabout, but there were no pavement markings in the circle at all, and traffic breezed through rather quickly.

Might have been the same one!  The worst one I saw was also on route 2, and was exactly as described... I would dread it every rush hour if I lived there, or maybe even find a way to avoid it.

[architect77]

There's no difference.

Sorry, I guess I was remembering this difference pointed out on Wikipedia related to 'roundabout':

In the U.S., traffic engineers use the term roundabout for intersections in which entering traffic must yield to traffic already in the circle, reserving the term traffic circle for those in which entering traffic is controlled by stop signs, traffic signals, or is not formally controlled.

Anyway, scary.

I loved the rotaries in Massachusetts. You could just barrel into them without slowing down and then exit where you needed to. People in the circle are already going slow so they can easily yield to newcomers into the circle.

[roadman65]

You have the many New Jersey Traffic Circles that are being eliminated one by one.

In Florida you have places like Windermere, FL who used them to get rid of four way stop intersections.

[kphoger]

How about this one?
[image]

I might be an odd one but Turbo roundabouts make a lot of sense to me. Bring 'em stateside!

It's almost like a collapsed turbine interchange.  Almost. 

[Duke87]

What exactly is the benefit of a turbo roundabout over a conventional roundabout? It separates traffic by destination more but it creates more conflict points.
(also removes the ability to make a U-turn)