burst its banksif a river bursts its banks, water from it goes onto the land 〔河〕决堤burst its banks• Residents were evacuated from the town as the waters rose and the Ouse threatened to burst its banks.• The River Frome had burst its banks after torrential rain and the Rovers' ground was absolutely waterlogged.• The River Deben had burst its banks and people's homes were getting flooded.• Denied its usual egress, the river had burst its banks and was pouring down the fire-ravaged streets.
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