South Yamhill River

South Yamhill River
Bridge over the river at Sheridan
Location of the mouth of South Yamhill River in Oregon
EtymologyUncertain but probably after a local Kalapuya tribe
Location
CountryUnited States
StateOregon
CountiesPolk and Yamhill
Physical characteristics
SourceNorthern Oregon Coast Range
  locationSiuslaw National Forest, in western Yamhill County, Oregon
  coordinates45°06′38″N 123°43′40″W / 45.11056°N 123.72778°W / 45.11056; -123.72778
  elevation551 ft (168 m)
MouthYamhill River
  location
between McMinnville and Dayton, Yamhill County, Oregon
  coordinates
45°13′33″N 123°08′41″W / 45.22583°N 123.14472°W / 45.22583; -123.14472
  elevation
75 ft (23 m)
Length60 mi (97 km)
Basin size492 sq mi (1,270 km2)
Discharge 
  locationMcMinnville, Oregon, 5.6 miles (9.0 km) from mouth
  average1,801 cu ft/s (51.0 m3/s)
  minimum0.58 cu ft/s (0.016 m3/s)
  maximum47,100 cu ft/s (1,330 m3/s)

The South Yamhill River is a tributary of the Yamhill River, approximately 60 miles (97 km) long, in northwest Oregon in the United States. It drains an area of the Northern Oregon Coast Range, as well as part of the Willamette Valley west of the Willamette River.