The Washington Water Power Co. has asked Idaho regulators to approve a temporary $2.3 million rate increase.
The proposed change would add $1.19 to the monthly bill of an average residential customer using 1,071 kilowatt-hours of electricity.
If approved, the increase would take effect Sept. 1 and expire Aug. 31, 1996.
Such adjustments are allowed when streamflows alter the amount of inexpensive hydropower WWP can produce at its dams on the Spokane and Clark Fork rivers.
Despite winter moisture, flows on the Clark Fork did not reach normal levels until April, the company said.
Since its implementation in 1989, the adjustment mechanism has yielded an equal number of rate increases and decreases.