mdman I cannot tell you when peak activity is, sorry.
BUT if you google Conowingo Dam and go to the official site you will find a phone number that you can call
the day before and it will list/announce the next day's generating schedule.....that is when they release the water, the fish in the resevoir
above go through the turbines and get stunned, some even killed, and this makes it easier for the eagle to pluck the fish from the water.
See my next pic.