Spokane, WA-based Avista Utilities has asked regulators to approve rate increases totaling $14 million, or 10.4%, effective Nov. 1, in part to cover purchased natural gas costs following Canadian supply disruptions last winter.

Separately, Avista requested electric rate changes tied to power costs and a third rate adjustment, which affects both electric and natural gas service. For gas operations, the rate adjustment is designed to increase revenues by $4.8 million (3.6%).

The total proposed hike in gas revenues is $18.8 million (14%). It would be the first increase in purchased gas adjustment (PGA) charges in five years.

"This rate adjustment is driven primarily by higher wholesale natural gas prices in the 2018-2019 winter season, which were caused, in part, by a Canadian pipeline disruption that restricted natural gas flows into the Pacific Northwest," said Avista spokesperson David Vowels.

From 2015-2018, Avista's PGA charges for Washington were reduced collectively by 35.4%. Included in the PGA are natural gas commodity costs and the cost to transport gas in interstate pipelines to Avista’s local distribution system. 

The PGA filings are weather and/or infrastructure outage sensitive.

On Friday Avista also filed a PGA request with Idaho regulators for an increase in overall gas revenues of about $3.3 million or 5.6%, also to take effect Nov. 1.