I agree with Salmo that fish always die in hatcheries. Sometime a lot, sometiimes a few. We need to know the difference between losses that are more or less acts of God, where the system gets overwhelmed and losses that are more or less intentional. There have been losses, rather large ones in fact, that were the result of simply not cleaning the incubation trays for weeks, not testing the emergency generator, and the like. These are reasonably preventable losses while stuff plugging in a downpour, breaking, and the like are not predictable.

As Darth noted, hatchery production in WA is massive with lots of sites and a massive amount of coordination necessary to bring it off.