John Rowland wrote:
"Earl Purple" wrote in message
oups.com...

Only Northbound traffic from the Wood Green end of
the A105 would have to take any real diversion - they
could go ahead then right into Oakthorpe Road. Larger
vehicles should use Lordship Lane then join the
A1080 and A10, or go ahead then turn right
into the A111 Hedge Lane.

This would go against planning principles. A better solution would be to
create w/b to e/b u-turning loop west of the junction - I am pretty sure
there is enough room there for it. Any traffic from the south to the east
would turn left at the junction and then u-turn.

Traffic from the A406 coming West should turn off at the Great
Cambridge roundabout then head along A111 Hedge Lane.

Or use the u-turning loop and then do a left.

There is some space in Bowes Road but I don't really think there'd be
enough for a U-turning loop there, plus it has the disadvantage that
some of the right-turning traffic must negotiate the junction twice,
thus increasing the volume on the junction. Plus the U-turning loop
would have to be signal-controlled, and would be too close to the
junction and two signal-controls close together spell bad news (the
main problem of the Great Cambridge junction - I know I was planning to
push more traffic onto it. However it's on the North Circular I'm
trying to increase the flow). Remember it's the lorries that would be
using it - the small cars are more likely to use Oakthorpe Road. Your
solution might work though if built well, i.e. the A406 gets a longer
green. (Without right-turns, the A105 would not require such a long
green).