Laying down some RF reflective paint/markers on the road wouldn't be nearly as expensive as other proposals (like embedding electronics or special wire underneath the road surface), it would be similar in expense to pavement markers[0] that are applied to some roads today, plus with a HUD it could even help human drivers in snow environments. Lots of places make special modifications to the road specifically for snow, and especially for snowplows.
[0]: http://www.highway-markers.com/pavement-reflectors/PM290.htm...
If you can get your car to self drive here, I assure you, your car will run anywhere on earth.
Let alone the seemingly indefinite construction zones that have become commonplace across America - often with the lane markers missing or going off in directions that do not exist anymore (old lanes now blocked, etc...).
I had not heard about that but that sounds interesting and I would love to learn more. Any sources you can point me at?
What sort of "source" do you expect would exist for this? It's just the day-to-day job of DOT.