Galloping Powerlines: What They Are and Why They Can Cause Outages

Areas in south London experienced extended outages during a snowstorm in February 2025. The cause was galloping powerlines, which is not a common reason for outages in London. This blog describes what galloping powerlines are, how they can lead to outages, and why they can take longer to fix.

With their strong winds and icy conditions, winter storms can bring treacherous driving conditions, cancelled school days, and unexpected power outages. One of the more unusual culprits of a winter storm outage - Galloping powerlines. While it might sound like a term from a Western movie, galloping lines are a serious issue that can cause outages and take time to resolve. Let’s break down what galloping lines are, why they happen, and why they can take longer to fix than other power disruptions.

What Are Galloping Powerlines?

Galloping powerlines occur when strong winds combine with ice or snow buildup on electrical wires, causing them to sway or “gallop” in a wavelike motion. This can happen because the uneven ice creates an aerodynamic shape that reacts to the wind, much like an airplane wing. The force of this motion can lead to:

• Wires slapping together, leading to short circuits and outages.
• Strain on equipment, such as poles, insulators, and other infrastructure, potentially leading to long-term wear and damage.

Why Do Galloping Lines Take Longer to Fix?

Restoring power when an outage is caused by galloping lines can take longer than usual for several reasons:

1. Frequency of the Event: The wires only hit each other for brief intermittent moments when the winds are just right, making it hard to locate the problem area as it comes and goes.
2. Safety Concerns: Once located, the unpredictable movement of galloping lines makes it dangerous for crews to work on them until the wind calms down.
3. Widespread Outages: Galloping lines can affect multiple areas simultaneously, leading to extensive outages that require more time and resources to fix.
4. Access Challenges: Snowstorms can make it difficult for crews to reach affected areas, further delaying restoration efforts.

What Has Been Done to Prevent Galloping Lines?

Weather conditions are changing quickly. While it’s impossible to eliminate the risk completely, we have taken proactive steps to minimize the impact of galloping lines, such as:

• Regular monitoring to identify vulnerable areas where galloping is most likely to occur.
• Installing line spacers in areas that are prone to galloping.

• Ongoing maintenance to ensure preventative measures are working as they should and any potentially strained equipment or damaged equipment is replaced.

  Image

  

What You Can Do During a Galloping Line Outage

• Be prepared. Have an emergency kit with essentials like flashlights, blankets, and backup power sources to stay safe and warm during an outage.
• Stay away from powerlines. Galloping powerlines are unpredictable. If you see a downed line, never approach or attempt to touch it—always assume it is live.
• Report damage. Contact us at 519-661-5555 if you see extensive damage, such as a downed line or equipment that is sparking and dangerous, so we can prioritize repairs.

While outages caused by galloping lines are rare, we understand that any power outage, especially extended ones, can be frustrating. We appreciate your patience while our crews work safely and quickly to restore service.

During winter storms, please stay safe and warm!