Bottom line - worth fishing just about year round. If you have a boat, then you don't have to worry too much about the flows - just make sure you have some visibiltiy and adjust your tactics to match the conditions. Faster and higher water usually means fishing tighter to the bank and vise versa...

I was just there last week and it was SLOW. Very wade-able and pretty, but cold. If you find a warming trend and the flows are reasonable, that would be your best bet. Anyway, I was also wondering when they usually open up the dams more for irragation? That's when I back off because my favorite spots to fish tend be under too much water then...