I spotted this south of Dupo, IL on Interstate 255, about a mile east of the bridge over the Mississippi River. This simply can't be the way the transmission engineer back in the office designed it! And if it's such a good idea, why only one?

Also, when I was looking more closely at this, I noticed the jumper between the top two wires (not counting the static wire). What's up with that? And, the top strings of insulators have 16 discs, whereas the suspensions have 11. What is going on here?

Well, ask and you shall receive. Dustin Logan replied:

The line post, the jumper, and the dead end strings on the top phase of this tower, all look like part of some emergency repair---possibly due to damage caused in an ice or wind storm. But that is just a guess.

On the second question, dead-end strings always have more disks than the suspensions, on a given line. Horizontally-mounted disks have a greater amount of surface leakage, than those mounted vertically. On vertical suspensions, the bottom face tends to always stay dry. Whereas, the rain can wet ALL of a horizontally mounted dead-end. So, on just about any line, the suspensions will only have 2/3 to 3/4 of the number of disks, found on the equivalent dead-ends.

Then Pat Scott, who lives in the area, added these details:

Steve, here are a few pics that will help explain your two questions.

First, that is an arrester. I have never seen a station post arrester hung like this, but the whole line is this way.

As for the jumper only on the top, that is because this is a three phase 138 kV circuit, and all of the lines are jumpered a couple miles north of where you took this shot. The phases only need to be jumpered in that one spot, but at each arrester they are jumpered again in case the conductor on the left side takes a hit, it can go to the arrester right at that tower.

Big Arrester: [id=286826117]

Lots o'Bells: [id=286826060]

This just seems like a photogenic line.

Tower line and lightning: [id=284084710]

Tower just before sunrise: [id=274707423]

Tower line disappearing into the distance: [id=140611524]