TVA starts the fall lowering for 2 reasons at least I was told this by one of the workers at gville dam. One is for weed control as the lower it is when the real cold stuff comes in it kills the milfoil back .The other is in anticipation of winter cold fronts bringing in lots more rain both at Guntersville and up stream this time of year into the early Spring.Its called flood control you flood the land with a dam and try not to let it flood anymore HAHA .The lake is low now but it stayed the highest I can ever remember all summer. I had to use my waders almost every time I fished a bridge. But I think its at least 2 ft down now. Also the amount of water released by Guntersville is controlled by a computer system located in Nickajack in Chattanooga. When they say they are spilling at Guntersville it just means they have anywhere from 1 gate to 15 open. the amount spilling usually tells how many gates.If you see over 100000cft or more then there will be 10 or more gates open usually unless they got them raised real high. anything under 100000 is usually 2 to 8 . also factored in is the total discharge when they generate the turbines. If there are no gates open and the discharge is at 48000 cfs then they are running all 4 wide open that's all they can send with no gates open. 30000 usually means idled down some and under 20000 they have some shut off or just idled I don't fish if its under 25000 down the as the water is dropping real fast.