Dairy Creek (Oregon)

Dairy Creek
Dairy Creek just south of the Tualatin Valley Highway
Name origin: Probably first used by Hudson's Bay Company employees who ran a dairy near the creek prior to 1840.
Country	United States
State	Oregon
County	Washington
Source	Confluence of East Fork Dairy Creek and West Fork Dairy Creek
- location	near Schefflin, Washington County, Oregon
- elevation	151 ft (46 m)
- coordinates	45°34′11″N 123°04′22″W / 45.56972°N 123.07278°W / 45.56972; -123.07278
Mouth	Tualatin River
- location	near Hillsboro, Washington County, Oregon
- elevation	128 ft (39 m)
- coordinates	45°30′06″N 122°59′43″W / 45.50167°N 122.99528°W / 45.50167; -122.99528Coordinates: 45°30′06″N 122°59′43″W / 45.50167°N 122.99528°W / 45.50167; -122.99528
Length	10.55 mi (16.98 km)
Basin	226 sq mi (585 km2)
Discharge	for East Fork Dairy Creek, 12.3 miles (19.8 km) above confluence with West Fork Dairy Creek
- average	76.9 cu ft/s (2.2 m3/s)
- max	1,580 cu ft/s (44.7 m3/s)
- min	6.9 cu ft/s (0.2 m3/s)
Location of the mouth of Dairy Creek in Oregon

Dairy Creek is a 10.55-mile (16.98 km) tributary of the Tualatin River in the U.S. state of Oregon. It begins at the confluence of its east and west forks near the unincorporated community of Schefflin and meanders southeast across the Tualatin Valley to the Tualatin River near Hillsboro, in Washington County. East Fork Dairy Creek begins at 45°47′18″N 123°02′29″W / 45.788446°N 123.041498°W / 45.788446; -123.041498 (Dairy Creek East Fork source) in Columbia County, slightly north of its border with Washington County, and flows generally south for 22 miles (35 km). West Fork Dairy Creek, also about 22 miles (35 km) long, forms at 45°45′19″N 123°10′41″W / 45.7553899°N 123.178168°W / 45.7553899; -123.178168 (Dairy Creek West Fork source), near the unincorporated community of Tophill, and flows generally southeast. Before railroads displaced river boats on the Tualatin, some steamships also worked the lower section of Dairy Creek, with plans to go as far up stream as Centerville.