When Ice storms coat power lines, high winds can lead to lines that bounce and buck around. While rare, this movement is known as "galloping lines".
Power lines are designed to sway, but if a wire is weighted down with ice and is pushed around from wind it could move close to a grounded component or an energized conductor and a short will occur.
Galloping lines are a dangerous situation as power lines can touch one another or break and fall to the ground while energized.
Another safety concern is the ice, itself. Ice can form around power lines in a teardrop shape. This shape acts like a wing, causing the line to gain lift and rise with winds. With high winds, the ice could break off, causing unsafe conditions on the ground.
The power lines that NIPCO (Northwest Iowa Power Cooperative) uses to transmit power on its 69KV (kilovolt) high-voltage power lines throughout western Iowa are designed to withstand up to 1.5 inches of ice and 50 MPH (miles per hour) winds.
Our cooperative, who receives power and transmission services from NIPCO, works to ensure that our system remains reliable and safe in the face of whatever Mother Nature throws our way.
If you see power lines moving around forcefully, stay away and call the police or your local electric cooperative.