CMP begins annual spring line inspection by air

AUGUSTA, Maine - Central Maine Power has begun its spring inspections of its transmission lines by helicopter. The flights are an important part of the utility's annual inspection program to ensure safe, reliable delivery of power to homes and businesses throughout its service area.

Each spring and fall, CMP does a visual inspection of all of its transmission right-of-ways from the air. These flights help to spot potential problems with equipment, as well as signs of unauthorized use.

"Unauthorized uses in our corridors can pose a risk to our energy grid or the environment," said CMP spokesperson Gail Rice. "We want to be a good neighbor by preventing abuses such as off-road vehicle use or disposal of trash or brush."

In addition to the spring and fall visual inspections, CMP also flies over its entire transmission system in the summer using a helicopter equipped with infrared thermal imaging equipment to detect "hot spots" that might need attention.

"Our lines are exposed to the weather all the time, and extreme temperatures and precipitation can take their toll on switches, clamps, insulators, and other equipment," says Rice. "These devices often heat up if there's been minor damage or wear, so inspecting the lines with infrared equipment lets us find and fix problems before they cause a power outage."

CMP owns nearly 2,500 miles of transmission line. Along with completing the semi-annual visual patrols and the yearly infrared inspections, the utility does aerial checks following major storms or when it detects an abnormality such as a momentary outage or a change in voltage.