A few statements for you to consider:
Lets be realistic here. Not advocating for mistreatment of fish, but the fish in the Stave are there for a fishery, the stocking program there was never intended to create, rebuild, or augment a wild run of fish. It was intended to create another place for anglers to fish for Steelhead.
British Columbia hatchery steelhead are about as responsible as it comes if you want to talk about supposed "Impacts" that hatchery fish could have on a wild stock genetically. With the exception of very few transplant programs (the Stave is one of them as pointed out), all hatchery steelhead in BC are taken from wild, native (to the watershed they are stocked in) broodstock. This means that genetic impacts are minimal and the wild offspring of hatchery fish from wild native broodstock are about as fit as offspring from wild fish, in the wild. Consider that hatchery fish tend to home in on both their release and rearing site, and as their rearing and release sites get closer they tend to home in on their rearing site (aka the hatchery water source/area/channel). This helps isolate them to some degree from the wild fish in the river as well, or limit their upstream travel to some degree in many cases.
The problem with hatchery opponents up here is they quite readily cite data from American hatcheries on American rivers and try to use it here as if it's applicable. Hatcheries down there are starting to change their tune slowly but surely but generally hatchery steelhead programs down there would typically recycle hatchery steelhead constantly along with transplants were quite common. They began hatchery programs before the homing of fish to their native watershed was really fully understood and so convenience of collecting broodstock was the primary concern. It's much cheaper to just collect one or two broodstock sources for the initial broodstock (i.e. Skamania Summer runs) and then transplant those everywhere. And then when they return instead of having to get anglers to try and target and catch wild fish, why not keep costs down and simplify thing by taking hatchery fish for broodstock which seem to readily return to the hatchery channel. They are then continually recycled for many generations to the extent that they are partially domesticated and their ability to produce fit offspring, in the wild, is reduced, and if they interact on the reds with the wild fish, will compromise their offsprings fitness for one or two generations.
The thing that seems to be ignored is Rainbow/Steelhead interactions and offspring fitness. There ARE rainbow trout populations in the varying watersheds and they will spawn with Steelhead. We need to stop thinking of Steelhead and Rainbow as different and start looking at them as one big population of fish - some go to sea, some remain in the river. What cues or factors cause them to remain or out migrate are dependant on the individual watershed. I would imagine nutrient abundance in their watershed and possibly intensity of freshet might have something to do with it. Other factors as well. Obviously a cold, coastal watershed probably has less rainbow trout than a warmer fertile interior stream. But they are there and part of the Oncorhynchus Mykiss population.
No hatchery program is ever truly going to rebuild a wild Oncorhynchus mykiss stock - hatcheries should be utilized for fisheries and that is it. Utilization of fish for hatcheries should be done with the best interests of wild fish BUT a balance needs to be struck. The Stave is a great candidate for a hatchery fishery.
There are some rivers that might be good candidates for Summer run Steelhead transplants fisheries.