The agency says the Coquille was more than 2 feet above its flood stage Monday morning at the town Coquille, and widespread flooding is expected along the river estuary.
The agency said low-lying roads in the flood-prone region will likely be covered, and some farm buildings may be threatened.
Farther upstream, the weather service said, it has cancelled a flood warning for the South Fork of the Coquille River at Myrtle Point. The river has fallen below flood stage.
The weather service says the Rogue was nearly two feet above flood stage at Agness. It predicted mild flooding, with the possibility rapid rises could affect boat docks.
One man was arrested after he went to check on his boat dock on the Umpqua River near Roseburg and it broke away while he was on it. He twice refused rescue but eventually decided to leave the dock.
He was not hurt, but he was taken to jail. It's now known what happened to the dock and boats.
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