Avista Corp., of Spokane, announced this morning that it has reached a partial settlement agreement with the Washington state Utilities and Transportation Commission on proposed electric and natural gas general rate case filings.

Under the partial agreement, a typical residential electric customer using an average of 966 kilowatt hours per month could expect to pay $2.81 more a month, for a bill of $84.03 rather than $81.22. A residential natural gas customer using an average of 68 therms per month could expect to pay $4.70 more, for an increase to $72.86 from $68.16. Avista spokeswoman Casey Fielder says both increases are estimates and might change based on what the commission approves.

As currently agreed upon, the electric rate increase would generate an additional $17 million a year for Avista, down from the requested $33.2 million in additional revenue. The natural gas rate hike would increase the utility’s annual revenue by $11.3 million, down from $12 million as originally proposed.

The remaining issues to be resolved in the rate case include capital investments in infrastructure improvements and recovery of utility operating costs.