A recent posting on the IEEE’s Spectrum Magazine website offers an interesting story of how power utilities have learned to deal with the potentially devastating effect of bird droppings on high voltage power lines.
According to the posting’s author, Charles Choi, the story goes back over 100 years, when high-voltage electric lines were being strung across the Sierra Nevada Mountains. However, the utility companies noted unexplained short circuits that resulted in power interruptions lasting seconds to minutes every two to three days.
Careful observations of the lines eventually revealed that the short circuits were initiated by contact with bird droppings from eagles who were perched on the lines and then emptied their bowels upon takeoff!
The solution? Utility operator Southern California Edison installed barriers and spikes to prevent eagle roosting, as well as excrement catching pans to prevent contact with the lines. Eventually, more sophisticated technologies were implemented to make the lines more impervious to bird droppings.