Mainly paddle open (canadian) canoes.
This road is not yet named in Google Maps but is named the Bunbury Outer Ring Road in some reference material. It's a nice location approximately 6km downstream of the access point at Dardanup Road West.
Not a recommended start or finish point but can be used as a bail out option if you find that you're fighting to make your way downstream due to low water levels. Due to fencing the only practical egress is by driving in from the Bunbury end of the road and parking on the left hand side immediately after the footbridge. Access to the river will require paddle craft to be lifted over the low section of hand railing (about waist high) on the footbridge section.
On the other hand- it is a nice spot with open grass to get out of the boat and enjoy a snack break. Given it's remote from town and well fenced there was no evidence of litter or graffiti when I stopped by.