Avista is entering the second year of our comprehensive 10-year Wildfire Resiliency Plan to systematically strengthen the electric grid infrastructure along the wildland urban interface (WUI) areas across Idaho and Washington. The plan includes defense strategies such as grid hardening and vegetation management, as well as operating practices such as ‘dry-land mode’ for a safer and more resilient system.
Wildfire safety and prevention is one of Avista’s most important objectives as a business and as an active member of the local communities we serve. The frequency, size and impact of wildfires in Idaho and Washington has grown exponentially over the past several decades. The threat of wildfire poses a real risk to Avista, our customers and communities.
In hot, dry conditions, Avista undertakes temporary changes to power line operations as part of our operational approach to mitigate risk. These changes are made to decrease the potential for wildfires that could occur when re-energizing a power line. We call this operational approach ‘dry-land mode.’
In most cases, under normal conditions, lines located in rural and/or forested areas are re-energized automatically following a fault or after being de-energized. However, when hot, dry and windy conditions are forecast, the distribution system is operated in ‘dry-land mode’ which includes having Avista’s line personnel physically patrol an outage area before a line is placed back into service. This can require more time to restore service but decreases the potential fire danger. These changes are made seasonally, and Avista returns to normal operations once the dry conditions change.
For example, most times of the year, if an electric circuit that brings power to your home or business is interrupted, it quickly comes back. The grid automatically tests the circuit and can generally come right back on. You have probably seen this happen when the lights go off for just a moment but come back on almost instantaneously. In extreme weather conditions, we switch operations to dry-land mode so the power lines do not immediately re-energize. The line isn’t back on until an Avista crew physically inspects the line to ensure there is no risk or chance of sparking. It takes a bit longer for power to come back on in these cases, but it’s a best practice we know makes a difference.
We have been implementing dry-land mode in response to hot, dry weather for more than 20 years. As part of our Wildfire Resiliency Plan, we have expanded this response by pairing it with our enhanced fire-weather dashboard and making protection in higher risk areas more sensitive when extreme weather is predicted. We return the system to normal as soon as weather permits and fire potential decreases.
Another part of Avista’s Wildfire Resiliency Plan involves an elevated approach to vegetation management, particularly in targeted, high risk geographic areas, to reduce the risk of trees making contact with electrical lines. In addition to increasing the inspection frequency of the trees growing near Avista’s transmission and distribution lines, electric customers in high risk areas may be eligible for a program where Avista will remove and replace incompatible trees with low growing, compatible species.
An additional part of Avista’s plan, our ‘grid hardening’ initiative which began last year, makes our system more resistant to threats so it can sustain more severe weather. Over a ten-year period, more than 3,100 miles of structures and targeted equipment in high risk areas will be replaced and/or strengthened with fire-resilient materials such as steel vs. wood poles, installing a special fire-retardant wire mesh around the bottom of wood poles and replacing wooden cross arms with stronger fiberglass arms to reduce the threat of wildfire events.
As the risk of wildfires increases, Avista is committed to deploying effective measures with the goal to prevent, mitigate and reduce the impact of wildfires to ensure safety and reliability in the communities we serve.