I believe that the hatchery failed because the sockeye themselves are failing in the system. Smolt numbers down, predation in the Cedar on fry can be really high some years, more in-lake competition (smelt) and the water is too clean. Add to that the increased temperatures in the Ship Canal and your pre-spawn mortality jumps.

The massive pink and chum hatchery production from Alaska, Jaan, and Russia are creating massive problems in the N Pacific. Note that Fraser sockeye, without the aid of hatcheries, are crashing too.

Lake WA, with all the species present and other habitat issues, simply can't support sockeye any more.