TVA's Nickajack Dam

Nickajack is TVA's newest dam on the Tennessee River. It replaced the Hales Bar Dam, about six miles upstream. TVA acquired Hales Bar in 1939, at the same time and from the same company (Tennessee Electric Power Company) as Great Falls Dam. Hales Bar was constructed on an unsuitable substrate... it was said that there was more water going under the dam than through it or over it! TVA decided it would be too costly to try to fix the dam, which had an inadequate lock anyway, so they built Nickajack (properly!), closing it in 1967. They then dynamited most of Hales Bar, although some of the remains are still visible. Here are three shots of whats left.

Now, downriver to Nickajack Dam.

Nickajack is one of the few main stream TVA dams that does not have bridge over the river associated with it.

It is listed as 81 feet high by 3767 feet long.

The Powerhouse is good for 100 megawatts.

The Lock at Nickajack is one of the new 600 by 110 foot locks that can accomodate up to 9 barges at a time, so that locking through a 15 barge tow is not such a painful experience.

The "Mule" at Nickajack. Obviously a cable/winch arrangement. We never did figure out why it was out in the open like this.

We thought that since Nickajack was relatively new, that the large lock was original. Maybe it was not. This shot shows whats left of another lock, where the lake side gate would have been. The lock looks to be about 60 feet wide, like the other older locks. Another puzzle: why didn't they keep the original lock as an auxilliary? Or did they change their minds during construction? The Corps of Engineers' literature says that the large lock began operation in 1967, the same year the dam was completed. More research to do...

Here is a view of the floodgate cranes. Because of the terrain upriver, Nickajack Lake has no flood storage capacity.

On the way back from Edgar Evins State Park, we picked a route that would allow us to see the south side of the dam. This is the preferred vantage point for now, since access to the lock visitor's center is no longer allowed. Easy to find from TN 156, this side allows a much better view of the dam, since the lock blocks most of the view from the other side. We couldn't even see the floodgates from the north side. And you drive right by the switchyard to get to this parking lot.

The back side of the powerhouse, from the south side.

A couple of times now we had seen this blue arc from I-24 in the vicinity of Nickajack Dam, and wondered what it was. Now we know... it is the bridge where TN 156 crosses the Tennessee River, just downstream from the dam.