Urban density complicates above-ground utility infrastructure. Undergrounding increases reliability and reduces overhead hazards, but only around 20% of electric distribution lines in the U.S. are undergrounded, largely in the densest urban areas. Above-ground utility and telecom infrastructure is still common in older, smaller or shrinking cities and in city outskirts. These poles are often aging and can be more difficult to maintain or replace because of limited access and congested work areas.

Composite poles are one option utilities may consider for addressing some of these urban infrastructure challenges.

Installation and Maintenance Challenges

Installing and maintaining utility and telecom poles in city environments can increase the access, cost, and resiliency challenges experienced on any line.

Perhaps the chief challenge in any location is access. Where rural environments often lack the access roads needed to bring truckloads of utility poles to a site, urban areas have a congestion problem. Significantly increased traffic from both vehicles and pedestrians means that temporarily shutting down even a single lane can worsen traffic, interrupt businesses and present increased collision risks for line workers. Workers must complete projects efficiently while maintaining safe work practices.

Whether municipally/publicly owned, private-owned or a co-op, utilities seek to keep costs down. Urban installations may require increased costs for permits on lane closures and zoning, in addition to the cost of the poles and the line workers. Frequent pole replacement or maintenance means repeated costs.

Installed conditions represent enormous, recurring challenges to urban utility and telecom poles. Snowy cities have to keep roads clear and safe, which commonly means road salt. Sometimes called “salt kill” or “salt defibration,” the damage caused by deicer and road salt can degrade wood poles the same as if they were installed as marine pilings. This causes a “fuzzy” appearance, and repeated cycles of saltwater wicking and drying can reduce structural integrity. Salt buildup can also lead to tracking and fires. Concrete poles have similar issues with cracking and spalling. Chemical treatment can reduce the impact of salt damage, but careful attention must be paid to meet local groundwater protection standards, as these chemicals can leach.

Winter conditions slowly deteriorate wood poles, but vehicle impacts take them out quickly. Most utilities know of at least one pole location that experiences repeated vehicle strikes. Each impact requires a professional inspection to determine whether the pole has retained its structural integrity or must be reinforced or replaced.

Copper wire theft is a large concern in urban installations, in addition to natural pest damage (woodpeckers, termites) and damage from public use (stapled fliers, graffiti). Grounding wires run along the exterior of a wood pole, making the copper easy to access—and to steal. This is costly for utilities and potentially dangerous if a pole is left ungrounded.

City poles are repeatedly punctured as residents and businesses staple fliers, and many end up covered in graffiti. While these don’t threaten pole performance, staples and graffiti affect appearance and can require greater maintenance.

FRP Poles for Urban Applications

When cities must replace aging or damaged poles, Fiber Reinforced Polymer (FRP) composite poles offer characteristics that may help address some urban challenges over a longer service life.

FRP poles are lighter than many traditional pole materials of the same diameter and length with a high strength-to-weight ratio. A lighter pole requires less  specialized lifting equipment and less time to place, helping crews complete work more efficiently and safely. Composites also have good dielectric strength, reducing line worker electrocution risks.

Although composite poles are typically much more expensive than wood, their lifecycle cost is lower because of reduced maintenance and longer service life. FRP is inherently corrosion-resistant and can withstand harsh environmental conditions like heavy storms, snow and wind. It is used for subtransmission and distribution lines in conditions prone to corrosion or where installation access is difficult. FRP is also less conductive than steel and can flex more than concrete during vehicle impacts.          

When it comes to impacts from vehicles and weather, composite poles behave differently than traditional pole materials, able to flex more than concrete and able to return to their original shape more than wood. Composite poles will break much sooner than other materials due to their low shear strength and hollow FRP construction, which can increase safety for drivers who collide with the pole. Even if sheared off, the lighter weight of a composite pole may be temporarily supported by the conductors, rather than dropping the entire line to the ground. A staggered installation in Missouri and Illinois, for example, has helped Ameren with their grid resiliency efforts. Highly resilient composite poles incorporated into mostly wood pole lines is helping the utility reduce cascading outages.

Composite poles are light and flexible while maintaining structural strength, some even strong enough to be installed unguyed. Some pultruded composite poles can also be extremely low-profile at groundline, allowing easier installation in a very tightly packed urban setting. Additionally, grounding wires run through the hollow inside of composite pole, at least 10 feet above ground, deterring copper wire theft. The smooth, nonporous surface isn’t inviting to pests (without chemical treatment that can leach into groundwater), can’t easily be staple-gunned and makes it easier to remove graffiti. The poles can carry multiple services, including power, telecom and streetlights. Some manufacturers can also offer custom-tint poles to meet a city’s aesthetic vision.

Case Study: Hoboken

Hoboken, New Jersey, turned to composites when updating the city’s telecommunication poles. City officials asked their telecom provider to seek a solution that would be both functional and attractive. They chose 10-inch FRP poles that:

• Resist corrosion, rot and rust, even after repeated harsh winters.
• Match the community’s chosen aesthetic with a custom color tint.
• Eliminate chemical leaching.
• Are designed to withstand hurricane-force winds.

The telecom poles have been standing like-new in the Mile Square City since their  2019 installation.

Cities demand solutions that install efficiently, provide long service life and minimize maintenance. Pultruded FRP poles offer material properties to consider for utilities evaluating above-ground infrastructure needs.