I have this UR complaining that you can’t get to water lane.
For this to work correctly I am guessing I have to allow a U Turn here. This is why I would like advice please. 
I myself would just ignore Waze and drive there but that is not the way to solve this.
I wouldn’t allow what Waze calls a U-turn; that is the ability to reverse direction and go back along the same segment.
But I think you could allow a right turn from the unnamed segment heading SE onto the W-bound Lower Thames St segment. Waze doesn’t allow turns which are too tight, so I’d tweak the shape of the unnamed segment to reduce the angle a bit. But not too much as you don’t want to generate an instruction if carrying straight on. If you enable the Junction Angle Info script, it’s colour-coding will help find the optimum angle.
Ian
I was going to go for a 90 degree turns but then you said “don’t want to generate an instruction if carrying straight on.” So I have now gone for less than 41° going straight and 137° for the Turn Right on to Lower Thames Street.
Hopefully this was what you think should be done. I also noticed that Petty Wales is No Motor Vehicles at certain times so changed it to a private road.
Sorry for sticking nose in - it’s not a good week already, with me spending the afternoon in A&E checking whether I’d broken my wrist (not, fortunately), otherwise I’d have got involved sooner.
There’s an interesting comment by the reporter which suggests that the former right turn into Water St(/the un-classified length of Lower Thames St) from the eastbound A3211, which shows up in older Streetview images, has been re-enabled. This means we need a link from the eastbound carriageway added. I’ve not been along Lower Thames St for ages, and with all the CSH work going on (nearly completed, hopefully), I’ve not a clue about the current layout, so I’m loath to add it.
Streetview images also show that this segment should be two-way, and we should probably have a place marker for the Public Car Park, about which there’s no trace on Google Maps, so would need a visit to get information. I’m planning on visiting the Aldgate area on Saturday, as that’s the day it’s due to reopen, along with checking other changes in the Blackfriars area. I’ll add this to my list of things to check, unless someone’s going there sooner.
You are most probably right John. I read it for the getting to Water Lane from the main road. I forgot about the right turn.
All I can tell you about Lower Thames street when I went down it last week is we now have a 2 way cycle lane on the North Side and only one lane eastbound. I am not sure if there are 2 lanes westbound.
Watch the London Marathon from the weekend it might give you clues and also you can see loads of 20mph zones. Also you can see the Security Point at Westferry Circus. They did mention in the commentary for the Marathon that TfL was rushing to get things done before the Marathon took place. So to save going there have a look on BBC iplayer 