....and regarding the washouts; if there's a spot in the road where the stream is flowing through, the prudent thing to do is turn around and head back. Next best thing to do is walk the stream (yes, getting one's feet, knees, thighs wet as needed) and ascertain the speed, depth, bottom surface of the water stream and the surface beneath it. If one can't safely walk it, it's prolly not entirely safe to drive.
.....as noted, the Nabesna cut-off includes/leads too/goes through some spectacular country. Back in the day, one could occasionally get visited by the Ellis boys dropping in with their -18's.
CRL
My RV is a 1946 PA-12
Back in the GWN