Roundabout hysteria

In My Humble Opinion
221

I prefer roundabouts to traffic lights, but unfortunately idiots abound…

People of my country. First, thank you for remembering that those little orange lights on all four corners of your car exist.

In a two lane roundabout, there are simple rules.

If you intend to leave the roundabout on the first exit, stay in the outer lane, using the appropriate indicator (seeing as this board is largely US based, that would be the right indicator, it is the reverse in left-side countries)

If you intend to leave at any other exit, use your left indicator in order to inform other drivers you are entering the inner lane, then use the right indicator to alert other motorists that you intend to enter the outer lane, and eventually exit at your chosen off-shoot.

DO NOT USE THE INDICATOR IN ANY OTHER WAY!

Having been a small bike (bicyle, 200cc Vespa, 125cc Yamaha) rider for most of my life, those indicator signals are a matter of life or death to me. I need to know your intentions.

222

I was always grateful when a driver used their indicators after changing lanes. Not as good as indicating before changing lanes, but at least told me that they intended to stay in the new lane, not veer back across to the original lane.

223

In an American two-lane “modern roundabout,” you’re not supposed to change lanes. If you’re using the inner lane, you enter and exit it without ever using the outer lane (except to cross it).

This is not really intuitive based on the other traffic rules, and it has resulted in some roundabouts in my area being re-striped for only a single lane of traffic because two lanes just didn’t work. On new ones, they make sure to put up multiple signs warning people to yield to traffic in both lanes, because people were entering the outer lane not realizing that they were going to get broadsided by the oncoming car in the inner lane.

224

I have absolutely no idea how to operate the roundabout @Lord_Feldon just described.

I liked @scudsucker’s clear explanation. Still, those are procedures utterly unfamiliar to me; I’d not expect anyone here to operate through it the way he describes. I sure wouldn’t know what to do.

225

You just follow these directions. If you’re in the left lane, you either go straight or turn left. If you’re in the right lane, you go straight or turn right.

226

That still doesn’t help me much.

Assume a 4-direction two-lane roundabout with two inbound and two outbound lanes on each of the 4 roads meeting the circle. Also assume the roads meet the circle 90 degrees apart. Trying for the most vanilla possible case here.

I believe there will 4 identical signs like that; one at each of the 4 entrances. So every driver has been given the same instructions. All that differs is whether any given driver is going 90, 180, or 270 degrees around the circle. We can temporarily ignore the folks needing to go 360 around the circle because they need to reverse course back out onto the road they came in on. But that case will occur too.

If everyone intended to exit at the 90 or 180 point it’d be very simple. Nobody would ever use the inner lane. But that’s not realistic. And defeats the purpose of having an inner lane.

So now consider me approaching the circle, intending to exit at the 270 point.

I properly get into the left inbound lane then merge into the stream of passing cars in the inner circulating lane. Thereby having to also cross between cars passing through on the outer circulating lane. I may have to stop on the inbound road to await an aligned opening in both outer and inner lane traffic before I can safely enter.

But eventually my opportunity comes and I survive entering across the outer lane into the inner lane with no transferred paint. Now I’m circulating in the inner lane passing first the 90 degree point then approaching the 180 point.

When I pass the 180 point and am now approaching my intended exit at the 270 point now what?

I can’t simply turn right from the left lane to exit because some traffic in the outer lane may be continuing past there to the next + 1 exit. They entered the circle from the approach road that was at the 90 or 180 degree point from my entry’s POV but are only going 90 or 180 degrees around the circle from their entry’s POV. And it’s not obvious I’m permitted to or should change lanes from the inner circulating lane to the outer circulating lane in that last 90 degrees of circulation so as to be able to make my unobstructed right turn onto the outbound 2-lane road. And if I am expected to lane change while in the circle, then the left lane of the exit is never used.

So I need to find an opening in the outer lane traffic that I can pass through on my way from the inner circulating lane to the left outbound lane. And if that’s not forthcoming I need to stop in the circle short of my 270 point to await an outer lane opening coming around to me? Or should I just keep circulating forever as the traffic load builds until the entire circle is now nose to tail cars and nobody can enter or leave?


Overall this smells a lot like the problem a cloverleaf has: two streams of traffic are merging into a very short stretch of road that then diverges again with everyone who entered from the left side wanting to end up on the right and vice versa. A recipe for crunches for sure, and doubly so if one stream has need to be accelerating while the other stream has need to be slowing. Which they definitely do in the cloverleaf case and probably mostly do in the two-lane roundabout case.

227

The traffic in the outer lane shouldn’t be that close. One of the rules on entering multi-lane roundabouts is that one yields to all traffic to one’s left, even that in the inner lane when the entering vehicle just wants the outer lane. There’s also a rule that one doesn’t pass cars in roundabouts. Everyone should be going about the recommended speed for that circle, which is usually 15 to 25 mph. So there should be adequate cushion to take the exit from the inner lane.

228

My new subdivision has a few. And yes it’s about slowing down cars.

We have some signs. “Only you can prevent speed bumps” and “Watch out for children dogs and toads”

229

You do not “merge” in a roundabout, you wait for traffic to clear. “Merging” suggests entering traffic and matching speeds. If someone at the 180° point “merges” next to you before you hit your exit at 270° and they continue straight (through you), they are in the wrong.

230

This advice from the UK Highway Code might help: (Transposed for those who drive on the right and go anti-clockwise round roundabouts)

On approaching a roundabout take notice and act on all the information available to you, including traffic signs, traffic lights and lane markings which direct you into the correct lane. You should

  • use Mirrors – Signal – Manoeuvre at all stages
  • decide as early as possible which exit you need to take
  • give an appropriate signal. Time your signals so as not to confuse other road users
  • get into the correct lane
  • adjust your speed and position to fit in with traffic conditions
  • be aware of the speed and position of all the road users around you.

When reaching the roundabout you should

  • give priority to traffic approaching from your left, unless directed otherwise by signs, road markings or traffic lights
  • check whether road markings allow you to enter the roundabout without giving way. If so, proceed, but still look to the left before joining
  • watch out for all other road users already on the roundabout; be aware they may not be signalling correctly or at all
  • look forward before moving off to make sure traffic in front has moved off.

Signals and position. When taking the first exit to the right, unless signs or markings indicate otherwise

  • signal right and approach in the right-hand lane
  • keep to the right on the roundabout and continue signalling left to leave.

When taking an exit to the left or going full circle, unless signs or markings indicate otherwise

  • signal left and approach in the right-hand lane
  • keep to the left on the roundabout until you need to change lanes to exit the roundabout
  • signal right after you have passed the exit before the one you want.

When taking any intermediate exit, unless signs or markings indicate otherwise

  • select the appropriate lane on approach to the roundabout
  • you should not normally need to signal on approach
  • stay in this lane until you need to alter course to exit the roundabout
  • signal right after you have passed the exit before the one you want.

When there are more than three lanes at the entrance to a roundabout, use the most appropriate lane on approach and through it.