I'm going to my sisters in Kamloops for thanksgiving on Sunday so I'll definitely give it a try while I'm up there. I've never fished the T before so I'll most likely be doing more sightseeing than threatening steelhead.
The problem with the low Thompson steelhead return maybe that the Thompson river is too healthy. Resident rainbow can produce anadromous trout and steelhead can produce offspring that do not go to the ocean.
" Anadromous steelhead and resident rainbow trout did not arise from two distinct evolutionary lines. There is a close genetic and taxonomic relationship between these two forms. Anadromous forms of the trout can convert to resident populations when drought events or damming of rivers blocks their access to the ocean. Conversely, resident trout populations can become anadromous if ocean access becomes available. It is typical to have both life history patterns occurring in the same stream. In fact, resident and anadromous parents can produce offspring of both varieties. It has been speculated that there is a food availability related trigger which determines whether a particular fish emigrates to the ocean or remains in the stream. It may be that if there is abundant food in the stream and a fish is growing at a rapid rate, it will remain in the stream. If food is limited and growth is slow, the fish will have a tendency to emigrate. "
http://www.naparcd.org/fish_trout_rainbow.html