Columbia River PUD board members adopted a 4 percent rate increase for electrical service at the agency's Aug. 16 meeting.

The rate increase is primarily a result of wholesale power cost increases, which account for 60 percent of the PUD's operating budget, according to a prepared release.

Starting Oct. 1, an average residential bill will rise by $2.87 per month, from $71.90 to $74.77.

After the increase, PUD residential rates will still be 25 percent lower than the average rates for all Oregon electric utilities, according to the release.

This is the first PUD rate increase in a decade.