Utility pole

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Pole carrying electricity, Cable TV, and telephone equipment (top to bottom). Two pairs of shoes can be seen hanging from wires.

A utility pole, telegraph pole, telephone pole, power pole, or telegraph post is a post or pole upon which telephone network equipment is situated. Similar poles are often used for electricity cables (with pylons being used for only the higher voltage applications) and frequently a pole will share both power and communications lines. Telegraph poles first became commonplace in the middle 19th century, carrying at first one steel wire, then in urban areas many. In Central Canada, the poles are commonly referred to as hydro poles, as the electric companies commonly have "Hydro" in their name.

Utility poles are usually wooden (cedar), but vary greatly from nation to nation. Other common utility pole materials are steel and concrete, with composites (fibreglass) also becoming more prevalent. In some countries, for example the UK, poles have sets of brackets arranged in a standard pattern up the pole to act as hand and foot holds for those working on the equipment or connections atop the pole. In the USA such steps are usually provided only for the upper part of the pole; the worker normally uses climbing spikes to reach them.

The appearance of poles has changed with technology through the 20th Century, with for example the loss of the stereotypical but now redundant crossbeam used to mount rows of insulators for open wire telephone circuits. These more traditional poles can sometimes be seen unaltered beside non-electrified railways, or where no effort has been made to remove crossbeams not in use.

However in the countries of Eastern Europe, in Russia and in countries of the third world, there are still many utility poles carrying bare wires mounted on insulators not only along railway lines, but also along roads and sometimes even in urban areas. Errant traffic being uncommon on railways, their poles are usually less tall. In the UK, many wooden poles carry elecricity from super pylons to the user at lower voltages (240 V to 11 kV depending on type, and often in three phases). The conductors on these are bare metal connected to the posts by insulators.

Poles in Ottawa.

Today utility poles may hold much more than the uninsulated thin copper wire that they originally supported. Thicker cables holding many twisted pair lines or coaxial cable or even fibre-optics may be carried. Simple analogue repeaters or other outside plant equipment have long been mounted against poles, and often new digital equipment for multiplexing/demultiplexing or digital repeaters may now be seen. In many places, as seen in the illustration, the providers of electricity, television, telephone, street lighting, traffic signals and other services share poles, either in joint ownership or by renting space to each other. Such poles provide a safe gap between power lines on top and signal wires below.

Wooden utility poles and railroad ties are almost always treated with creosote to slow decomposition. This is also the most common way of preserving wood in the United States.

Throwing poles similar to utility poles is a traditional Scottish sport known as the caber toss.