The rockslide is a few years old (2006 I think). I have no idea if they intend to ever clear it (it was BIG and the canyon wall is unstable, picture
here).
It is pretty much a semi-permanent pair of bridges they have set up (way back in the day the road used to be on the other side of the river anyway) to cross over. It isn't a big deal except for being one lane and therefore you can end up waiting 20 minutes for your turn.
I didn't mean to say the rockslide was an obstruction, just that I find it something cool to see.
Here's more information on the slide, its impacts, and some possible long term plans for a fix. There's even a video of driving over the bypass bridges.