So obvious out of towner making the trip to the Oak for the first time. It looks like PFD's are required in the vicinity of the Dam? Is this hardcore inforced? In the videos i see of people fishing there I dont believe I have ever seen a PFD on any of them. Any insight is greatly appreciated. 
 

http://orleansoutdoor.com/steam-conditions/
 
Read the whole thing he's got some info on where they are required (mainly by the dam and in the overflow channel).

The PFD "request" is not enforceable. This info came directly to me by the NY DEC officers in the area. The majority of the yellow area in the pic below, everything North of the old trestle, is NOT Brookfield property, DEC will do nothing if you are fishing there without a PFD. The small yellow area just below the falls is Brookfield property. Again, DEC will not enforce wearing a PFD, because "Not our job to police their private property".  

Brookfield placed several of these signs on NY State land / waterways illegally.

Now, is it a good idea to wear a PFD in the rapidly changing water conditions below the dam? Probably. But you are not breaking the law if you don't wear one.