The dam is so big that it is hard to get an overview picture from the ground. This is the control structure and hydroelectric plant. You can see a couple of the cranes on the left that are working on the new lock.
the centers are open except during high security alerts. (Is this link now, 20161220, broke because the center is open?) But I have not found out how to get a "further notice" and thus whether or not it would be worth trying to visit the center during later trips.
The control room is empty because the dam is run from Chattanooga. "It had been raining for days and the head technician, Jeff Ring, was upset with 'Chattanooga' because they had the spillway gates open even though the reservoir had not reached its capacity. The technician said 'We’re spilling without making power. We’re losing money by doing that'" [DailyYonder]
http://industrialscenery.blogspot.com/2016/12/tva-kentucky-lock-and-tows.htmle parking lot as close to the water's edge as I could get. I'm used to seeing just one or two Extra High Voltage lines leaving a power plant. Four smaller lines reminds me that 1) this plant does not generate much power (199 Mw, brochure) and 2) the consumers are smaller towns spread across a large geographical area.
They have another parking lot down by the spillway because the Visitor Center is on the left of this photo. Note the two gantry cranes near the middle. They can roll across the top of the spillway and raise and lower the gates. The gantry crane on the left is a lot bigger than this view shows.
the railroad bridge, I didn't get a good picture of the switchyard next to the parking lot. Fortunately, it was in the background of this picture of the Kaplan turbine.
Zooming in allows me to count 11 discs in an insulator. My notes near the end of power lines indicates 12 discs handle 230kv. So the four lines leaving this switchyard are around 210kv.
Tainter gates I'm used to seeing in river navigation dams. They look like sluice gates. The river flow was low when I visited because only three of the five hydro units were running. So none of the spillway gates were open. But in this picture below taken during the 2011 record flood, they are open. Since the gates are not visible, they must be lowered down inside the concrete spillway instead of the normal technique of raising the gate.
Update: This PDF file describes the construction of the new lock.