Tualatin River

Tualatin River
The Tualatin River in northwest Oregon
Origin	Northern Oregon Coast Range
Mouth	Willamette River
Basin countries	United States
Length	miles ( km)
Source elevation	450*0.3048	}}}} m)
Mouth elevation	85.61 feet above sea level
Avg. discharge	Annual at mouth: 6940 cu ft/s (200 m³/s)^[1]
Basin area	sq mi ( km²)^[2]

The Tualatin River is a tributary of the Willamette River located in Oregon, USA. The river is approximately 83 miles (125 km) in length. It drains a fertile farming region called the Tualatin Valley southwest and west of Portland at the northwest corner of the Willamette Valley.

Description

The river originates in the Northern Oregon Coast Range in southwestern Washington County, near the town of Cherry Grove and flows northward, passing south of Forest Grove, then generally eastward, passing south of Hillsboro, then southeastward through the town of Tualatin. Its confluence with the Willamette River is located to the south of West Linn. The drainage area of the Tualatin is approximately 712 square miles. Its watershed is 15% urbanized, 35% agricultural, and 50% forested.^[3]

The valley of the Tualatin was an important early farming region in the settlement of Oregon. The building of a plank road to the Tualatin Valley from Portland in 1860 is considered by historians to be one of the principal reasons for the rise of Portland as the dominant city in the region. The valley contains numerous natural wetlands, some of which have been designated the Tualatin River National Wildlife Refuge and others are protected at Jackson Bottom Wetlands Preserve.

The Tualatin River bears the name of a local Native American tribe that lived in the Tualatin river valley. Early settlers called it the Quality River.^[4]