The Boardman Coal Plant is generating electricity again after repairs to a steam pipe that cost $10 million.
The 3-foot diameter pipe was knocked off its hangers July 1 by thermal water hammer, which is caused by a sudden change in pressure from mixing cold and hot liquids.
Portland General Electric announced the repairs were completed last week.
The East Oregonian reports no steam was released in the incident, and no customers were affected by the shutdown, as PGE spent more than $3 million on replacement power.
The Boardman plant is scheduled to end coal-fired operations in by 2020. PGE is building a natural-gas powered plant at the facility.
PGE serves more than 800,000 customers in Portland, Salem and the northern Willamette Valley.