Yakima River

The Yakima River is a tributary of the Columbia River in south central and eastern Washington state, named for the indigenous Yakama people. The length of the river from headwaters to mouth is 214 miles , with an average drop of 9.85 feet per mile . It is the longest river entirely in Washington state.

The river rises in the Cascade Range at an elevation of 2,449 feet at Keechelus Dam on Keechelus Lake near Snoqualmie Pass, near Easton. The river flows through that town, skirts Ellensburg, passes the city of Yakima, and continues southeast to Richland, where it flows into the Columbia River creating the Yakima River Delta at an elevation of 340 feet .

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