I may have mentioned this before but, especially with steelhead, it seems that large (in excess of 100K) plants are necessary to get good returns. Some of this may be that a plant of 10-20K may represent 5 or fewer females so inbreeding can be a problem.

Consequently, I would be more inclined to support single large plants versus scattering them around to a lot of streams. Pick a few rivers with, besides a hatchery that can raise them, great access to boat and foot anglers and good collection facilities. lastly, one must be willing to write off the wild stock in that river.