Could a senior editor please look at this UR
The reporter is asking for U-turns to be restricted at the lights - however if I am honest I’ve not come across this sort of layout before.
Once this is editted could you please notify me so that I can learn from it - I am sure its obvious.
Cheers
Mark
You seem to have posted the wrong link but I assume you mean this junction and the reporter is getting U turns on Witan Gate.
I messed around with this junction last year as we were getting U turns on Avebury Blvd and due to the distance between the carriageways the only way I could get it to work was by adding the extra segments that you can see at high zoom levels. I thought at the time that Witan Gate was OK and haven’t seen any other UR’s here for several months.
It might be worth playing around with the angles of the Witan Gate intersection to get it closer to 180 degrees although I thought it was within limits.
Sorry the correct link is this one
It looks like the problem is that the changes made to the junction are preventing the “proper” u-turn prevention mechanism from working.
To recap the mechanism - if the route goes through a segment shorter than 15m by making two right turns whose total is very close to 180°, this will be seen as a u-turn and avoided.
The problem involves this segment. Going from/to the SE, the first right turn is 89° and the second is 86°. The total angle of 175° isn’t close enough.
Now, since I’ve been with Waze, I have seen so many arguments over whether the critical segment length is 15m or 10m, or whether it’s different in different parts of the world, that I’ve long given up being sure and always try to aim to <10m. :roll: I’m guessing that the unusual segments AndyPot2 put in were intended to avoid reported u-turns coming from NE or SW. That suggests 10m is the correct figure for the UK. As such, they should work fine, although I’m unhappy about these four segments which are all shorter than 5m - something which Waze have advised us to avoid. Unfortunately, that’s where the 175° angle comes from.
Rather than trying to tweak a complicated junction and leaving such short segments, I would suggest removing the extra segments and bringing the 2 sides of Avebury Boulevard closer together so they are 10m apart at the junction. Then, a bit of careful tweaking with JAI should be able to prevent u-turns from all directions without strange constructions or short segments. :mrgreen:
Thank you for your input Iain.
Could someone please take up the challenge - I am sorry but I really am not confident enough to undertake this one
Done :mrgreen:
All 4 segments now below 10m/32.8ft; all u-turn combined angles within 2° of 180°; locked to L4 for protection. :ugeek:
You can close the UR now.
bump 
@The Madcabbie can the UR be closed now please? Thanks