The following is a press release from Pacific Gas & Electric Company:
Pacific Gas and Electric Company will fly a helicopter saw along four electric transmission lines that span from Humboldt to Trinity Counties to improve electric reliability, starting Friday, December 8. A helicopter saw, or heli-saw, is a series of circular saws suspended from a high-performance helicopter used to trim the tops and sides of trees. PG&E uses the heli-saw in remote areas to maintain safe and reliable service to its customers in Humboldt County.
Unlike trees growing in dense forests, trees growing along transmission line corridors tend to grow more and longer branches because there is more sunlight. In addition to the risk from the growth, these limbs collect snow and can pull the tree over in the direction of the line during storm events. PG&E will prune the limbs to prevent future power outages and to increase public safety. A helicopter saw is a safe, efficient way to prune trees in remote areas where snow and muddy roads make accessing power lines challenging.
The four transmission lines run through remote areas East of Eureka. Work will occur between Kneeland Road in Humboldt County and Big Bar in Trinity County. Property owners along the 42 miles where the pruning will take place have been notified in advance.
This targeted reliability project is one part of PG&E’s robust vegetation management program in which the energy company prunes or removes approximately 1.4 million trees annually. PG&E’s 70,000 square-mile service area includes approximately 123 million trees with potential to grow or fall into overhead power lines.
PG&E inspects and monitors every overhead electric transmission and distribution line each year, with some locations patrolled multiple times (18,000 transmission miles plus 81,000 distribution miles is about 100,000 miles of transmission and distribution lines).
Before the heli-saw, a small helicopter (four-passenger A Star) will conduct an initial fly-over of the transmission lines to review terrain, pruning areas, roads, creeks, and other general avoidance areas. The heli-saw will fly 7 days a week, from 8:00 a.m. to 4:00 p.m. Work is expected to be complete within the next three weeks.