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The Bogachiel River (/ˈboʊɡəʃiːl/) is a river of the Olympic Peninsula in the U.S. state of Washington. It originates near Bogachiel Peak, and flows westward through the mountains of Olympic National Park. After emerging from the park it joins the Sol Duc River, forming the Quillayute River, which empties into the Pacific Ocean near La Push, Washington.

The Quillayute River system, with its main tributaries of the Bogachiel, Sol Duc, Calawah, and Dickey Rivers, drains the largest watershed on the north Olympic Peninsula.

The name "Bogachiel" is a corruption of the Quileute words bo qwa tcheel el, or /boqʷač'íʔl/, from /bó:q'ʷa/, "muddy", and /číʔlowa/, "water", meaning "gets riley [turbid] after a rain", "muddy waters", or, less likely, "big river".