Underground or Overhead Service Feeders

The Differences Between Overhead and Underground Wiring

Overhead power lines
Douglas Sacha / Getty Images

When dealing with service entrance cables on new homes, the question often comes up about underground and overhead feeders. Are underground feeds better than overhead feeds? Well, to determine which is best for you, we’ll look at the differences and how each may benefit you. As far as the utility company is concerned, one is just as good as the other and they can install either one for you. But there are differences and here they are.

Underground Service

Underground services are, well, underground. The wires are connected to the utility company’s pole, fed down a pipe into the ground, and through a bored hole in the ground, run into a ground-based transformer. That’s called the line connection, or the primary connection to the transformer. The secondary side of the transformer has wires connected to it that are bored to the electric meter connected to a pole or side of your home. The advantage of the underground feed is that there are no visible wires present and that eliminates the possibility of trees falling on overhead wires. It is a much cleaner look and also eliminates the unsightly power poles strung across your yard.

Overhead Service

Overhead service feeds are just that, overhead. They implement power poles that string feeder wires from the utility company’s pole to the power pole by your home. From there, the feed will either be underground or an overhead feed to a service mast through your roof or mounted along the side of your home.

Overhead feeds use triplex aluminum wire that is much cheap and less time consuming than underground wiring. At $1.50 a foot or more for underground feeder wire, it can get quite costly to install underground rather than overhead lines. Also with overhead feeders, you can get a utility light added on top of the power pole, but without the poles for overhead, underground installations don’t have that to offer.

Due to a road-widening project by my home, I’m lucky enough to have just received underground feeders to my home, replacing the overhead feeders that have been here for over 20 years. It comes at no cost to me, so it is a welcomed change and that eliminates my worries of my wooded lot dropping a tree limb on the power lines and taking out my power. I’ve got to tell you, I love the underground, but you always have to keep in mind the safety factor of each.

Safety Factors of Underground vs. Overhead Feeders

Safety? Yes, safety factors for underground and overhead feeders. You see, with overhead lines, you have to watch that tall trucks, farm implements, augers, and such don’t get tangled in them. With underground feeders, you have to watch out when you are digging. That’s right, hidden underground is a disaster waiting to happen! Before you dig, call the underground marking hotline in your area. Let the appropriate utility agents come and mark the power, water, sewer, phone lines, and gas lines before you dig. This simple call can keep you safe!

The Process of Switching From One Feeder to Another

Due to that recent road project in front of my home, I got to experience the whole operation of changing my power over from an overhead feed to an underground installation.

The utility company dug a hole in the front yard where the transformer base was to eventually sit and another near the utility pole. Then, they dug another near my existing pole which houses my service drop.

In my case, I opted to leave the pole to save my pole light. In my case, they simply ran the feed to the top of the pole and connected to the overhead service weather head. In any case, the wire was run by using a boring machine that drills underground from one location to another, without disturbing any more of the above ground, other than the holes dug.

Trenching would have left a long trench and disturbed grass. The boring machine drills through the ground and is led by a remote device that another worker keeps moving in a predetermined path from hole to hole. It is quite a sight to watch them accomplish this procedure.

Once the drill gets to its destination, a pull-tip is added where the bit was and they pull the wiring right through the hole they just made. It is as slick as can be and the yard looks great! I personally like the natural appearance of my front yard now versus the power poles that were there previously. If you have a choice, maybe you'll agree that underground is better?