Here is a great video by La Grave Drones showing the new RD1091 relief road that opened this week. It is shot with a GoPro Hero 4 camera and a DJI Phantom Vision 2 Plus. Awesome gear and an awesome video.
The new relief road opened on November 23, 2015. The backup route, which is on the left bank of the Romanche is there to restore the traffic that has been cut off since the closure of the tunnel Chambon, April 10. The creation of this road represents an investment of about 5.5m€.
The road is slightly wider than planned. This involved carving into the cliff using some very dangerous mining techniques. They also opted for a slab of asphalt bitumen rather than a coating with gravel, in order to limit the drying time.
The Department of Isère have a 6 page pdf on their website which is a road safety guide for the RD1091 which is now called the RS1091. I have split this into 6 images: