Roundabout at Liffey valley, what lane?

DylanII wrote: »

Does anyone know what lane you should be in at the roundabout beside B&Q.

When your coming from Liffey valley and going towards ballyfermot/palmerstown which lane should you be in?

I always use the inside lane but about 70% of people use the outside lane when going to ballyfermot/palmerstown and the inside lane when going to clondalkin. They are both the same exit off the roundabout. But further up the road they are different turns?

Any link or pic would help.

If you are turning 90degree right then outside lane 1st or 2nd exit left lane unless arrows say otherwise

Matt Simis wrote: »

Surely this is the roundabout in question?
https://maps.google.com/maps?q=Liffey+Valley+Shopping+Centre,+Ireland&hl=en&ll=53.35371,-6.403667&spn=0.00129,0.004128&sll=37.0625,-95.677068&sspn=56.768363,114.433594&oq=liffey+valley&t=h&hq=Liffey+Valley+Shopping+Centre,+Ireland&z=19

Ive had many arguments with my brother about it. Im not sure who is correct, but I argue that going with the majority is safer than trying to make a point.

Leaving Liffey Valley, heading towards N4, Leixlip/West (away from Dublin) direction, I take the inside (closest to roundabout centre lane) lane around the roundabout then exit then immediately merge with the right side of double split lane which itself merges with the N4.

He argues its signposted "right" in the middle lane on the roundabout, leading to merging on that double laned joiner road on the left of the two lanes.


It seems to me the junction is setup to support both approaches, the only time you get a problem is if someone in the outside lane bypasses their first left and decides to slice 2 of the 3 exit lanes.

I'm fairly sure he's talking about the other roundabout and he is approaching it from the top left and exiting at the bottom. The important thing to note is that the bottom exit has three lanes exiting it. The left hand lane at the exit is a filter lane for a left turn ahead, the other two are for a right turn.

MYOB wrote: »

The markings are for a much larger roundabout. Its too small for the number of lanes on it.

+1 that the biggest problem with a lot of these roundabouts. Too many lanes. Too small roundabout.

I wasn't going to reply but,
The roundabout the OP is talking about at B&Q

Most times, very little traffic is going down the B&Q exit compared to the clondalkin and palmerstown/ballyfermot turn (P/B turn), as the turn to ballyfermot can get backed up, it makes sense for the nearside (left) lane entering the roundabout to be used for going down to the P/B turn off soley (instead of blocking up by queing in the righthand lane as this would only hold up traffic to clondalkin direction at no benefit to those wanting to turn to palmerstown/Ballyfermot) in particular when its busy and then use the right lane for clondalkin traffic.

Suprisingly enough that roundabout mostly seems to operate smoothly, as that is what most people do, except when people block it up as the P/B exit backs up and cars coming from the other direction also block the roundabout trying to get around.
If people didn't block it, it would work all the time.

In my opinion, both lanes should be right turning and have a painted sign on the road
The left lane should be left and right (obviously)

As for it having an exit missing, the main traffic flow would still be going right at that roundabout, coming from liffey valley, the priority (usage) isn't to B&Q and the other side of the car parks of liffey valley shopping centre.


Regarding the other roundabout, for the most part I think it's ok, except coming from Fonthill, the offside lane according to the road markings can only turn right towards liffey valley, it should have a straight arrow on there also as traffic from the near and offside has two lanes to the next roundabout beside the bridge.

At peak times, none of the road markings can be seen, so unless you are familiar, not that Im one for anymore signs, there are enough of those up, some blocking view of traffic at roundabouts.

The worst problem I can see at roundabouts is an upturn in the amount of people willing to not yield, not even look.

Iwannahurl wrote: »

There's a large sign to the left on approach to the roundabout (see StreetView link above) which clearly indicates the right turn, ie past 12 o'clock.

Re: "If people didn't block it, it would work all the time." Roundabouts inevitably give rise to circular arguments, it seems!

If roundabouts worked all the time, then people wouldn't be blocking them.

There are inherent problems with roundabouts at peak traffic times. That is why many roundabouts end up being signalised, or totally converted to signalised junctions as is happening on the N6 Bothar na dTreabh route in Galway.

I think they need to paint sectors of yellow boxes to encourage not blocking on roundabouts (where the lanes meet the roundabout, in between that leave spaces for people to move into), if every car moved up one space at a time it would leave the road unblocked, maybe. I know it wouldn't make a difference to a lot of people who will just ignore it, but some will follow it.

Lights on a roundabout that size will be an inconvenience most of the time and will inhibit the freeflow of traffic more of the time than the peak time traffic currently does, Im sure you're not suggesting lights there, just using an example of where it's necessary on larger roundabouts.