Tualatin River

The Tualatin River is a tributary of the Willamette River in Oregon in the United States. The river is about 83 miles long, and it drains a fertile farming region called the Tualatin Valley southwest and west of Portland at the northwest corner of the Willamette Valley. There are approximately 500,000 people residing on 15 percent of the land in the river's watershed.
The Tualatin River arises near Windy Point on the eastern side of the Northern Oregon Coast Range. It begins in the Tillamook State Forest in Washington County and flows about 83 miles to the Willamette River near West Linn in Clackamas County. Along the way, it falls from about 2,000 feet above sea level to about 60 feet , most of that occurring in its first 15 miles . From the unincorporated community of Cherry Grove, 68 miles from the mouth, the river falls only about 220 feet in meanders that trend generally east across the relatively flat Tualatin Valley.

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