The name of the waterfall and the river the forms it may have stemmed from Alsi, said to be a corruption of Alsea for native people who lived near the mouth of the river[3]
^McArthur, Lewis A.; McArthur, Lewis L. (2003) [1928]. Oregon Geographic Names (7th ed.). Portland, Oregon: Oregon Historical Society Press. pp. 19–20. ISBN0-87595-277-1.
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