Seattle recently installed its first protected downtown bike lane on Second Avenue. Here’s a short video of it in action (pay attention to the signalling setup and the pedestrians that walk into the bike lanes). Click here if you can’t see the video below.
Shortly after it opened, they quickly discovered that the left green arrow and solid green circle (shown above) were confusing drivers. The intent was for the left green arrow to signal that you could turn and for the solid circle to signal that you could drive straight ahead.
But even with the accompanying sign, drivers kept getting confused and thought a green circle meant you could go wherever you want.
So the Seattle Department of Transportation quickly adjusted and changed the green circle to a north arrow. And it seems to have fixed the problem. I think it goes to show how important the details can be with these things.