I wonder if its worth also getting info on the
http://www.mundabiddi.org.au/ which parallels the Bibulman for some of that area? Their FB page reports closures, I guess whether its open in May will depend on how much damage is done to the track.
https://www.facebook.com/MundaBiddiTrai ... am&fref=nf The other thing .... the Bibulman was substantially realigned I think over a decade ago. Parts of it still exist but have been renamed - there is a lovely section in the Wellington national park parallel to the river road -Honeymoon pool and other camping spots, then going North it was nearer to Harvey than Collie.
http://www.collierivervalley.com.au/col ... or-centre/ I wonder how much of this could still be walked if the Bib itself is damaged? South of Wellington forest, the Ferguson Valley has some dirt roads and somewhere the MundaBiddi goes through it, Crooked Brook is nice, then from Donnybrook it goes to Boyanup where I think you are back on the Bib? I get some of the ***up names muddled. Just a suggestion but it might be nicer than road walking, walking through soot or lots of detours, although I think there are a lot of forest roads in that area that would be alternatives. Enjoy! Oh, and there is a better range of wineries near the old track....