A Fight to Root Out Pipeline Corrosion
A California utility is locked in a showdown with private and public property owners over its plan to remove hundreds of trees that are damaging and corroding area pipelines.
San Francisco-based Pacific Gas & Electric, one of the largest natural-gas and electric utlities in the United States, says that trees, sheds, garages and other structures on both public and private property need to be removed
The trees are causing significant problems throughout the company's 6,750-mile-long pipeline system, PG&E has been telling residents and county officials statewide
Tree roots can rip the protective wrap from a pipeline and destroy its first level of external corrosion protection, PG&E says.
Kirk Johnson, PG&E vice president of Gas Transmission Maintenance and Construction, outlined the tree removal plan at an April 22 meeting of the Contra Costa County Board of Supervisors.
Decades ago, Johnson said, PG&E assumed that pipelines buried at least three feet deep wouldn't be bothered by tree roots. But now, he said, those roots are potentially putting systems at risk.
Not only can tree roots destroy a pipeline's protective coatings, but they can wrap themselves around the pipe.
Natural plantings and manmade structures can interfere with pipeline maintenance, inspection and operation, PG&E has said.
If the tree falls, say in an earthquake or wind storm, it can pull a small pipe entirely out of the ground, or put unusual stresses on larger pipes that lead to failure, Johnson said.
In the past, PG&E didn't stop residents from planting trees or building structures over pipelines; and once one person did it, many others followed suit.
Now, the company says, these structures are preventing crews from performing checks and maintenance.
"We became a little too customer-focused," Johnson said.
The utlity plans to remedy the situation with Pipeline Pathways, a five-year, $5 million, shareholder-funded program.
"This would eliminate—not mitigate, eliminate—the risk of external corrosion and wrap damage to our pipeline system from tree roots," Johnson said.
PG&E says it became "too customer-focused" by allowing people to plant trees and build structures over pipelines for decades. Now, the utility wants them removed for pipeline safety.
"We're not going to get here in the next five years. It's going to take a long time to get through all of the specific issues that cities and counties have," Johnson said.
Cities Want Negotiations
However, the plan is currently on hold while PG&E negotiates with multiple cities.
The Contra Costa Board praised Johnson for his focus on pipeline safety, but determined it needed more details before letting the utility move forward with its plan.
The company has marked hundreds of trees for removal throughout the Bay Area, NBCBayArea.com reported.
The mayor of Walnut Creek, CA, Kristina Lawson, told the news channel that 700 trees have been tagged in her area, and the city will sue to stop it if necessary.
PG&E says it won't remove any county trees or any "protected" or "ordinance" trees on private property without a written agreement in place.
The company is also working to meet with private property owners to remove "encroachments" (i.e., sheds, barns, garages and trees) and hopes to have an inventory for the counties sometime this summer.