You could do a 'season' like the Gauley or every other weekend or other options.

Fish might rather constant flow over daylight flushes, so I'm surprised fisherman would ask for that - sounds fishy.

But the 'locals would prefer' isn't really an argument for or against what a hydro-power facility does or doesn't do.

Having a 'Green Season' or 'Green Weekends' would increase traffic on those days for sure, as more people would travel from further away places .. possibly even flying in from other countries for a trip scheduled a year in advance.  But as Cheoah, Tallulah, Gauley and Green Race have shown us - unless you are playboating one spot, the more the merrier.    Put on early or late and you still have the river to yourself for the most part.  

C