Wildfire is a fire originating from an unplanned ignition source, such as lightning, volcanos, or human causes, that burns in what’s known as the wildland, which is generally underdeveloped and uninhabited land. Wildlands can include forests, grasslands, brushlands, and other ecosystems—even croplands. Wildfires can be dangerous when they start to burn out of control and move from underdeveloped wildlands to more developed and inhabited areas. In many cases, that line can be blurry. It falls in an area known as the wildland/urban interface (WUI).
Wildfire risk has historically been relatively low in the Pacific Northwest as shown on the Wildfire Hazard Potential map provided by the Forest Service. But increased wildland-urban interface, climate change and low snowpack have been increasing the threat of wildfire risk within Clallam County PUD’s service territory.
Clallam County PUD’s Wildland Fire Mitigation Plan (WMP)
A WMP is a set of strategies and actions to reduce the risk of wildfires. Utility wildfire mitigation plans include all the tools the utilities could use to prevent and respond to wildfires, including vegetation management, implementation of grid hardening projects and Public Safety Power Shutoff (PSPS) protocols.
While the PUD already had strategies and plans in place to reduce the risk of wildfires, recently, we provided a comprehensive WMP to the State of Washington per Senate Bill 5158. Washington state WMP’s are posted on the Department of Natural Resources website.
You can also view Clallam PUD’s WMP.
Vegetation management
One of the simplest and most effective ways to mitigate wildfire risk is through vegetation management. Trees and/or branches coming into contact with energized overhead powerlines combined with low humidity, high temperatures, wind and a source of fuel is one of the leading sources of utility-caused wildfires. Trees, brush, and other flammable vegetation around utility poles and power lines can act as fuel for fires. By maintaining defensible space around these assets, companies can significantly reduce the risk of fire spreading to critical infrastructure.
Clallam PUD employs two (2) tree trimming crews and one (1) right-of-way management crew. Tree crews safely remove trees and branches encroaching into the overhead powerlines, typically on a 5-year cycle, depending on the growth rate of the trees in the area. The right-of-way maintenance crew utilizes multiple head mowers mounted on a steel track excavator and a forestry model rubber track loader to mow brush and small trees.
Grid hardening
Utility grid hardening refers to the process of making the electrical grid more resilient and resistant to various threats and disruptions including natural disasters such as storms, lightning, floods, wildfires etc.
Wood power poles have an average lifespan of approximately 40-50 years. The PUD has standardized replacement (at the end-of-life) of these poles with stronger poles meeting current codes, specifications and clearance requirements. Example: Clallam County PUD has standardized fiberglass crossarms and transmission poles since 2012. Fiberglass is considered a fire-resistant material in utility applications due to its inherent fire-retardant properties, ability to withstand high temperatures, and limit flame spread. In addition, the lifespan of fiberglass is twice or more when comparing to wood poles and crossarms.
Wildfire Season and Public Safety Power Shutoff
The following strategies are used during the Wildfire Season:
- Crews take additional precautions and avoid parking on dry grass to prevent vehicle/equipment exhausts from causing fires. PUD practices heightened situational awareness. Crews are equipped with shovels and fire extinguishers.
- The right-of-way maintenance crew carries a 125-gallon water sled while mowing.
- Certain transmission lines are de-energized based on load requirements.
- A Supervisory Control And Data Acquisition (SCADA) system is used to make strategic and informed decisions towards changing grid control settings. For example: disabling reclosing operation under deemed conditions.
- Public Safety Power Shutoff (PSPS) is a practice to intentionally de-energize electrical power lines when elevated fire risk conditions exist to reduce potential fire ignitions. The PUD receives all of its energy from the Bonneville Power Administration (BPA) through delivery points in Sequim, Port Angeles and Sappho. BPA’s criteria for PSPS is wind gusts exceeding 60 mph within National Weather Service Red Flag Warning areas as the conditions correlate to warm temperatures and low humidity. The PUD monitors these criteria and stands ready to receive BPA’s PSPS plan to facilitate successful implementation. PUD’s distribution infrastructure would be de-energized in the vicinity of the affected BPA delivery points implementing the PSPS. If the PUD were to experience high winds combined with a Red Flag Warning within a smaller geographic area, then PUD’s distribution will be proactively de-energized. A link to BPA’s wildfire mitigation plan and PSPS procedure can be found here.
Clallam PUD is actively planning on grid hardening and resiliency projects like replacing wooden transmission structures with fiberglass structures, undergrounding the overhead electrical infrastructure in several areas, use of Advanced Metering Infrastructure to ascertain outage location (potentially caused by a fire during conducive conditions and improve response time).
The PUD also participated in the recently concluded Clallam County Multi-Jurisdictional Hazard Mitigation Planning (MJHMP) process and the plan identifies wildfire mitigation as one of the top priorities for the PUD.
Additionally, the PUD is currently participating in Clallam County’s Community Wildfire Protection Plan (CWPP) which focusses on identifying and reducing the risk of wildfire to life, property, and natural and cultural resources.
PUD urges all its customers to be prudent and responsible while handling outdoor recreational fires, perform a risk assessment, educate yourselves on methods of home hardening, creating defensible space, and treating fuels. More information can be found at several sources like FEMA, National Interagency Fire Center and others.