By David Kligman
GEORGETOWN—High above a home in this onetime Gold Rush community in El Dorado County, Damon “Wojo” Wojciechowski was harnessed near the top of a dead, 100-foot-tall ponderosa pine.
His job was to use a chainsaw to cut down the tree one large chunk at a time. There was no room for error as the Davey Tree Surgery contractor, working for PG&E, buzzed away at the tree, which was secured by two ropes to help guide the falling pieces.
And in the blink of an eye the giant treetop came crashing down exactly where the three-man crew had planned—avoiding the home, a shed and a 21,000-volt distribution electric line.
“Nice shot!” yelled Nathan Browne, his colleague stationed on the ground. “Right between everything, buddy.”
The ponderosa pine is among the 50 million-plus trees that must be managed every year in PG&E’s service area to avoid high-voltage overhead power lines. In this case, to avoid the likelihood of the tree falling on the electric line, the dead tree needed to be cut down rather than be pruned.
Keeping trees away from 135,000 miles of lines
The utility oversees the country’s largest vegetation management program, a year-round operation that includes 350 foresters and more than 600 contracted tree crews patrolling 135,000 miles of overhead lines from the Oregon border to south of Bakersfield.
On any given day vegetation-management crews and inspectors visit 15,000 properties.
Over the past 15 years, since the utility was fined after inadequate tree-trimming contributed to a wildfire, PG&E’s vegetation-management program has steadily improved.
Today vegetation management is a $182 million program that has led to major reductions in the numbers of vegetation-caused outages—from 30 percent in the late 1990s to 8 percent last year. In 2011, PG&E reduced the number of outages its customers experienced to an all-time low, and improved restoration times to their best level in 10 years. The company is on track to do just as well, if not better, in 2012.
“When I first joined this role I thought contractors trimmed trees and that this is going to be a cakewalk,” said Steve Tankersley, a 35-year veteran who has overseen the program since 1999. “It’s quite different. Our team deals with just about every public agency, city and county across the service territory and millions of customers.”
(Click here to read about a recent award won by Tankersley and PG&E’s vegetation-management department.)
Necessary for safety, reliability
Tankersley said one of the most important parts of his job is educating customers about the need for this work. It’s a constant message to homeowners and agencies that vegetation management is necessary to provide safe, uninterrupted power for everyone.
He points to the Northeast blackout of 2003—the second most widespread blackout in history—traced in part to a tree in Ohio that grew into a transmission line. The blackout on that hot August day impacted millions in seven states, New York City and other large metropolitan areas plus most of Ontario, Canada.
The utility is required to maintain safe clearance of its distribution and transmission lines but actually exceeds federal and state minimum limits—from 18 inches for lower voltage lines in urban areas to 20 feet for the highest voltage transmission lines.
Communication is important. In late September, homeowners in El Dorado and Nevada counties will receive letters encouraging them to use PG&E contractors (who are certified to work near high voltage power lines) rather than third parties for pruning trees close to electric lines.
Every spring, PG&E is out in the community participating in hundreds of Arbor Day festivals and at elementary schools. Their message is the “right tree in the right place.” What that means is encouraging the planting of low-growing trees that won’t interfere with power lines.
PG&E has been recognized by the National Arbor Day Foundation and as a Tree Line USA award-winning utility for the past 18 years in a row.
“Their partnership and support of the Arbor Day celebrations and promoting proper tree placement in their service area are some of the things that make them a good Tree Line USA utility,” said Randy Gordon, a program manager with the National Arbor Day Foundation.
Winter storms, summer wildfires
The work is demanding and there’s no letup. During storm season, from November to April, much of the work involves clearing brush and fallen trees that topple onto power lines or wind-blown limbs that short-out lines. From April to November, lines need to be monitored or cleared to reduce the risk of wildfires. And during wildfires, vegetation-management crews are often near the front lines helping protect power poles with fire retardant and removing vegetation near electric lines to create an additional fire break.
Tankersley and Jeff Mussell, a PG&E forester based in Auburn, recently provided Currents with an up close look at two tree crews in action. One was working on U.S. Forest Service land where four dead ponderosa pines were precariously close to a 21,000-volt line.
The other location was the home where the 100-foot-tall tree had recently died and needed to be cut down. Foreman Larry Thompson began the job by using a long checklist to assess the hazards, including pedestrians, motorists and weather conditions. A hard hat, safety glasses and gloves are always required.
“Our No. 1 priority is safety,” Thompson said.
Tim Hoy, the homeowner, said he was more than happy to let PG&E arrange to have the tree removed, especially since power lines border two sides of his home.
“I think it’s good preventative maintenance that they do it,” he said.
Hoy said he met the tree trimmers when they arrived at his house early in the morning. He would have watched, he said, but he had to get to his job at an auto body shop. When he returned, the tree was removed and no longer a safety threat.
“I left to go to work at 7,” he said. “It was all done and cleaned up by the time I got home at 6.”
Email David Kligman at David.Kligman@pge.com.