PG&E launches new electric infrastructure undergrounding effort to protect against wildfires

A new initiative launched by Pacific Gas and Electric Company (PG&E) in California this week aims to counteract the ever-growing threat of wildfires by undergrounding some 10,000 miles of power lines.

“We want what all of our customers want: a safe and resilient energy system. We have taken a stand that catastrophic wildfires shall stop,” Patti Poppe, PG&E’s CEO, said. “We will partner with the best and the brightest to bring that stand to life. We will demand excellence of ourselves. We will gladly partner with policymakers and state and local leaders to map a path we can all believe in.”

Traditionally, undergrounding efforts have been few and far between — done case by case and largely for reasons other than wildfire risk. With evolving technology and knowledge, however, PG&E feels comfortable enough to expand such efforts throughout High Fire Threat Districts (HFTDs) to help prevent fire risk. What will result is the largest U.S.-based effort to underground power lines for risk reduction purposes to date.

More than 30 percent of the company’s total distribution overhead system currently passes through the highest fire-threat areas — more than 25,000 miles of lines in all. While it is too early to adequately tell how much will be able to be undergrounded each year, PG&E intends to be able to make predictions following inspections, estimations, and engineering reviews. A system will need to be designed capable of moving around existing water, natural gas, and drainage systems or the future widening of roads.

While reducing the risk of fire, PG&E sees the payoffs for undergrounding as including a reduction in the need for vegetation management or Public Safety Power Shutoffs. The latter are major events that have become more frequent in recent years, generally called when dry, windy conditions could lead to vegetation sparking wildfires through contact with live power lines.

Some advances and lessons learned in recent years that make such undergrounding efforts more viable include, among other things, cost-effective implementation of new planning systems and strategies in concert with new materials and equipment. PG&E has also built up relationships with material suppliers and contractors to help hasten things and is working with other providers — such as natural gas, phone, or internet — to joint trench and share costs where applicable, even as new technology and construction methods increase trench production.