Grid Hardening Lowers Fire Risk, Increases Reliability
While most wildfires are started by lightning strikes or caused by human actions, utilities have a role to play in risk reduction -- and we are doing our part. And while we can't stop wildfires, we can make our electric infrastructure more resilient to better withstand fires by using new construction methods and materials and keeping our system maintenance up to date by replacing aging equipment.
EWEB employs a full menu of options for "grid hardening" strategies, including a robust vegetation management program, replacing older equipment on a regular basis, full system inspections, and in some cases, placing power lines underground.
One of the measures underway this summer and fall is the inspection and replacement of power pole crossarms. Our line technician crews have been working for the past several months to identify and replace older or deteriorating crossarms in the McKenzie River Valley service territory and on select circuits in south Eugene.
Replacing crossarms is a labor- and time-intensive process, where the crews are often working within a few feet of energized powerlines. However, this is one of the measures that could prevent EWEB facilities from becoming an ignition point for a wildfire.
During high wind events, such as the gusting, erratic winds seen during Red Flag Warnings, the failure of a crossarm could bring down energized power lines and potentially spark a fire. To help reduce that risk, crews are now finishing up the replacement of more than 100 crossarms in the McKenzie River and south Eugene areas.
"Our approach is to use multiple investment and replacement strategies to maintain reliability and increase resiliencies for all types of weather conditions the electric system must face," said Electric Operations Manager Tyler Nice.
"Most often mentioned as an improvement to mitigate fire risk is undergrounding lines, however, that option typically cannot be acted on right away, may not be feasible, or be cost prohibitive," Nice said. "Preforming inspections and turning around maintenance work quickly for high-risk areas and ailing equipment is not only a quicker option, but is financially responsible, and will provide reliable service for years to come."
Another risk reduction strategy is to replace wooden power poles with metal poles in areas that are at higher risk for wildfire.
This past spring, EWEB finished a project that used ductile iron poles to replace wooden poles in a section of its upper McKenzie River transmission line. The ductile iron poles are much more resistant to fire than wood. The project at Deer Creek is the first time EWEB has installed ductile iron power poles.
"Not only will the ductile iron poles prove more resilient in surviving a wildfire, but we actually improved habitat by placing the new poles away from Deer Creek, which is the largest tributary to the McKenzie River," Nice said.
Along with grid-hardening activities, we also conduct routine system maintenance to keep electric infrastructure functioning safely and properly throughout the year. The reliability work includes proactively pruning trees and removing brush to help keep our equipment clear of contact, and for access if an outage repair should be needed. In addition to the regular vegetation management, tree-trimming crews spend extra time pruning in areas at higher risk of wildfire.
Crews regularly inspect electric lines, poles, components and other equipment, replacing worn or older parts as needed. This work not only helps keep the system operating during snow, ice and windstorms, but reduces the likelihood of some types of equipment failure that may causing sparking that could ignite a wildfire.
