Hypoxia, IMHO, is the result of so many nutrients and the continued overharvest in the estuaries. Not talking about one area like the Canal only. But this is the problem child in my home waters.

Tacoma Public Utilities trucks it's sludge to be dumped in the greater canal drainage as fertlilizer for farms. Only thing is there are only a few farming families in the area.
This is a ruse to promote fiber growth on timberland. Sure they blame the older septic systems. But how many tons of treated sludge does this drainage really need?

I feel the anchovies have taken over the lesser desirable lower Canal.
Perhaps they can withstand the lower O-2 levels.