A mate of Emma's, who is a very careful driver, had a collision with a biker in a similar instance. She pulled up to a junction, looked both ways, and started to pull out. Biker appeared out of nowhere
Biker was found to be speeding, several signs had been badly placed and obscured her view of the road in the direction of the Biker's emergence but she still got prosecuted. Seems we are expected to be familiar with coping with 3rd world standards of road construction by now
I think if you don't have the right of way you're basically at fault regardless of the circumstances. Might be worth seeing if your legal protection will cover clobbering the council with a bit of grief, if nothing else. Matters will only improve if they get hassled.
Kevin