It was back to normal within two years.
That's actually not my understanding of it, when it happened. It has gotten better as I did more research about it, but its never gonna be the same is what I am saying, the population of fish will eventually get back up there but I think it was reported that around 500,000 adult and young salmon, steelhead, trout, lamprey and other species died of suffocation from "severe burns" to their gills from a "concentrated pulse" of caustic soda.
The animals that live off those fish and river itself will be affected too which makes sense, the whole food chain and what not.
But to hear that people are able to fish it again is good sign, and its been awhile so there has been plenty of time for nature to heal itself.
Regardless glad to see fishing is good. I think I'll probably stay away from it myself, I may try to fish it as I haven't really been there yet myself but for the most part I am in no hurry.