Story and photo by Larry Vogel

Think your power poles are growing? Here’s why.

A number of Edmonds residents have noticed taller power poles being installed along neighborhood streets, and have wondered why (See article here.)

According to Snohomish County PUD’s Neil Neroutsos, the taller poles are largely in response to an increase in non-electric utility pole attachments such as cable TV and telephone systems.

“We need to keep at least 40 inches of clear space between energized power lines and these other pole attachments,” he said. “Maintaining this means that new poles are typically five feet taller than the ones they replace.”

The PUD “rents” space on its poles to other entities (e.g., cable TV and phone companies) who want to attach their equipment. “We take in between $1.1-1.3 million per year in pole attachment fees,” said Neroutsos, “but that income is pretty much eaten up by the costs to administer the program.” These costs include general administration, inspections to ensure that adequate clearances are maintained, followup, etc.

While the increase in pole attachments is the most common reason for installing taller poles, there are other reasons as well such as upgrading local distribution from single to triple phase. This entails replacing a single power line with sets of three energized lines (phases in utility-speak)

“Triple phase gives us more capacity and allows us to meet increases in demand,” Neroutsos said

No permit is required to replace existing poles, and unless particular sensitivities exist in the community, public involvement, open houses, etc. prior to replacing a pole are rare. There are between 110,000 and 115,000 poles in the SnoPUD system. Barring early replacement driven by system upgrades, the average utility pole lasts between 30 and 40 years. The PUD replaces about 1300 poles annually.

In addition to the operational reasons, taller poles enhance safety by simply making it more difficult to accidentally contact energized power lines.

Typical neighborhood power poles consist of an upper cross arm holding the three wires that comprise the primary circuit feeder. These are bare, uninsulated wires usually operating at 12,500 volts. Beneath these are the secondary distribution lines carrying 220 volts which connect to individual homes’ service drops. The lowest lines on the poles are typically cable TV, internet and phone lines.

Note however that on some taller poles there are additional higher voltage lines at the very top. These are arranged in groups of three, and operate at 115,000 volts. These typically carry electricity between substations and other utility installations. The higher voltages allow more power to be moved over greater distances with minimal loss of efficiency.

Overhead lines have become an everyday feature of our neighborhoods, and it is easy to forget how hazardous contact with these lines can be. The Utility urges customers to take particular care with tree-trimming equipment, ladders, boat masts, etc. to ensure that they remain at least 10 feet from energized power lines.

“We try to keep our system as safe as possible,” said Neroutsos. “A big part of that is keeping our customers informed of the dangers of contacting overhead lines.” A good rule of thumb is the higher up on the pole, the higher the voltage and the greater the hazard of accidental contact.

But if you’re wondering about taller power poles, blame it on our increasing appetite for more cable TV channels, greater Internet speed and bandwidth, and increasing electricity demand. The wires that supply these amenities need to go somewhere, and for the present that means taller poles.