According to the United States Geological Survey fact sheet, "Largest Rivers in the United States", "Rivers are considered large on the basis of one or more of three characteristics: total length from source to mouth, area of basin (watershed) drained by the stream, and average rate of flow (discharge) at the mouth." The Columbia is the largest river of the Pacific Northwest in all three senses.
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"The Columbia River". Columbia River Keeper. 2013. Diarsipkan dari versi asli tanggal 2019-01-07. Diakses tanggal December 5, 2013.
"The Columbia River". Columbia River Keeper. 2013. Diarsipkan dari versi asli tanggal 2019-01-07. Diakses tanggal December 5, 2013.