Someone's just raised this on twitter:
"Manse Rd/St Johns Rd EH12 < 3 sec w/b cyclists to clear junction as lights change. Saw one very nearly t-boned!"
Anyone here know the area better than I do?
CityCyclingEdinburgh Forum » Infrastructure
Manse rd/ st Johns rd timings?
(26 posts)-
Posted 10 years ago #
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I live nearby. It's quite a bad junction for traffic on St John's Road sitting in the yellow boxes and preventing exit from Manse Road. There are often amber gamblers and red light jumpers, but there is a camera there.
Not sure I understand what this tweet is about: what does "w/b" mean?
Posted 10 years ago # -
Presume w/b is westbound?
That's why I was asking here. Sounds like cyclist was going e-w on St. John's, but lights changed such that car coming out of manse road nearly hit them?
Satellite image shows ASLs well back with, I presume, crossing in front.
Posted 10 years ago # -
West Bound is my guess.
Manse st is a one way North bound road ending with Tjunction with st johns road. It has 1 lane turning East and one for turning West.
The camera is on the main road so wouldn't have helped in this instance.
Its uphill from Manse st onto the main road which doesn't help with visibility but any WestBound cyclist should have been visible. The only thing I can think of is if there were pedestrians standing at the traffic island between the 2 Northbound lanes.
St John's Road isn't a great cycling experience and this just puts me off further.
.
Posted 10 years ago # -
Came back via Manse Road last night to check out the lights.
I took a video and looked at the timings tonight...
Time StJRd MRd
0sec Green Red
1sec Amber Red
2sec Amber Red
3sec Red Red/Amber
4sec Red Red/Amber
5sec Red GreenSo 5 seconds from green to green, which has to take into account reaction time as well as travel time to cross c.15-20m at 5m/s (12mph). Pretty tight...
Posted 10 years ago # -
I grew up in Corstorphine and that junction was 20 years ago notorious for giving priority first to E-W traffic along St Johns Road, then to traffic exiting Manse Road and lastly, as an afterthought, to pedestrians.
Nearly every shop that used to be in Corstorphine has gone out of business. I wonder if any of the owners considered why local people do such a good job of avoiding their own high street.
Posted 10 years ago # -
Timings increased from 5 to 7 seconds.
Win?
Posted 10 years ago # -
"Timings increased from 5 to 7 seconds."
Is that 'true' or just a recent observation?
Hardly sounds like much if it's actually a permanent adjustment.
Posted 10 years ago # -
west team says increased from 4 to 6 sec
Posted 10 years ago # -
Hankchief, the guy who originally raised the issue asked if you could time it and see if there's any difference?
Thanks!
Posted 10 years ago # -
No change to the timing that I could tell.
I even recorded it twice to make sure...
Posted 10 years ago # -
SRD - I've worked out what they have done...
They have added a pause to the end of the Manse Rd green before SJR gets to go.
But they have left the timing as it was from the end of the SJR green to the start of Manse rd.
Given the original incident was somebody nearly being hit from a vehicle leaving Manse Rd before the west bound SJR cyclist had cleared the junction, they have put the pause in the wrong place in the cycle.
.Posted 10 years ago # -
Slightly OT but does anyone know why there is a 6-7 seconds delay on St Johns Road after the lights on Clermiston Road turn red? It doesn't seem to serve any useful purpose at all.
Posted 10 years ago # -
Now, I don't want you to think that I make a habit of studying traffic light sequences, but I think the prolonged red at Clermiston Road is linked to the pedestrian crossing to the East on SJR.
I think the pedestrian crossing goes red (for cars) when Clermiston Road is green (I.e. Exiting onto SJR), but the main flow of traffic on SJR is held back until the pedestrian cycle is complete (whether or not the crossing lights have been activated)
I assume the god of traffic flow wouldn't allow a pedestrian phase as well as a Clermiston Rd phase and this was how they could squeeze one in.
Note that this also means that there isn't a signalled crossing of Clermiston Road, which means you can't walk along the North side of SJR with 2 toddlers in tow.
Posted 10 years ago # -
^ Yes, I know it is linked to the pedestrian crossing, but the prolonged red/red phase doesn't seem to achieve anything. The pedestrian bit is red for traffic when Clermiston is green and there is normally a sufficient amount of time to let people on foot cross during this period. I also notice that the pedestrian crossing goes red even when there is nobody in the vicinity of it.
Not that I am a student of this type of thing, but theses lights have always been a bit odd. They used to change together and then the pedestrian bit got more and more out of phase with the Clermiston lights. This was then rectified about a year ago when the 7 second delay appeared..... Yes it is on my (non rush hour) commute since you ask
Posted 10 years ago # -
SRD - did you get chnace to go back to the council about them putting the extra pause in the wrong place in the traffic light signal? . See my post 4 above this..
I was passing tonight and saw that the extra pause was still after Manse road's turn rather than SJR.
Posted 10 years ago # -
No, afraid I lost the plot on this. Not knowing the intersection, I wasn't sure I could intelligibly about it. Anyone else want to have a go?
Posted 10 years ago # -
Sure. Just let me know who you contacted before (either on here or by PM) and I'll pick up with them.
Posted 10 years ago # -
Hankchief - it was west team via twitter. Don't gave a name.
Posted 10 years ago # -
Thanks SRD.
I'm not on twitter so an old school 'e-mail' sent.
Let's see what happens...
Posted 10 years ago # -
Sucess...
I got a prompt response from the council and a pause has been added to sequence after SJR stops and Manse Rd starts.
Spotted it in action yesterday but wasn't able to stop and time it.
Impressed that they are able to react so quickly to changing traffic light timings..
Posted 10 years ago # -
well done you guys!
Posted 10 years ago # -
........however. I now notice that the pedestrian phase crossing Manse Road has changed. The green man remains lit and then goes to red just as the light for the road goes green. Previously there was a short pause with neither sign illuminated. Not only does this mean that people will have started to cross a nanosecond before the light changes, it also means that as a cyclist you don't get any warning that the StJ light are about to change as you get there.
Posted 10 years ago # -
Hmmm....
I think the problem is that anywhere you don't have a pause between one signal going red and another going green you are putting greater risk on those that are going through at the tail end of the green / amber gamblers / ealry RLJers won't have cleared the junction before the others start. However the longer pauses you have the lower the traffic flow.
I guess they have just moved the pause from after Manse Road to after SJR rather that increase the whole sequence length.
I've not yet been able to see the whole sequence for myself. What do you suggest would jmprove it? .
Posted 10 years ago # -
Stiltskin - I just had a look at the entire sequence and there is a gap between the pedestrian crossing on Manse Road going red and the manse road traffic going green.
Can you check whether you think this is now fixed next time you are passing?
There is now a pause after both traffic phases before the next one starts.
A good success I feel.
Posted 10 years ago # -
hey guys, I'm told that not only do (some of)the guys who work on light timings cycle, but they also read this forum (or at leastb this thread!).
cool eh?
Posted 10 years ago #
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