Lake Chelan expected below usual target ahead of spring 2027 power plant outage

CHELAN — Lake Chelan is expected to reach levels about 1.3 feet below its usual seasonal target in late winter and early spring 2027 as Chelan PUD prepares for a planned outage of both generating units.

Jeff Johnson, the PUD’s director of energy operations, planning and trading, outlined the anticipated change during a quarterly energy resources update to commissioners Nov. 2. The outage is scheduled for April and May.

At the lowest point, the lake is expected to be about 1.3 feet below the utility’s target curve, which tracks intended lake elevations through the year. The forecast presented to commissioners showed the lower levels ahead of the outage.

Johnson said the difference could appear more pronounced to residents comparing conditions with the preceding spring. A rain-on-snow event produced significant runoff earlier than anticipated, pushing lake levels above the target during that period.

“And because of all that, we operated higher or above that target curve last year,” Johnson said.

The projected 1.3-foot difference is measured against the seasonal target, rather than against the actual lake level from last year.

The forecast chart showed lake levels rising through April and May toward summer operating elevations. It identified the anticipated departure from the target as a late-winter and early-spring condition associated with the planned outage.

Separately, Johnson cautioned that it was too early to make definitive statements about the region’s 2027 water supply. Staff will continue monitoring conditions and updating forecasts. The quarterly presentation was informational, and commissioners were not asked to take action on the lake-level outlook.

Johnson said the PUD plans announcements and public outreach to explain the expected change before residents see the lower water levels.

“And so, we’re going to be getting ahead of that and doing some announcements and public outreach just to recognize and communicate this change,” he said.

Andrew Simpson: 509-433-7626 or andrew@ward.media