Our Watershed Facts

Our Watershed Highlights:

We have some of the largest Oak prairie habitat in whole Willamette valley, the most remnant of what used to be there. Because these habitats are now rare in the valley, they are especially important to safeguard and enhance for future generations.

The GYW is one of the largest west-side tributary watersheds in the Upper Willamette River Valley. Hundreds of miles of our streams are designated by Oregon Department of Fish Wildlife as essential and/or critical habitat for imperiled winter steelhead trout. Studies conducted over the last five years estimate that the Yamhill River Watershed receives about 4% of the winter steelhead trout returning upstream of the Willamette Falls each year. In addition, studies conducted in 2009 and 2014 indicate that the Yamhill River Watershed may support the highest population of naturalized Coho salmon (38-48%) in the Upper Willamette River!! 

Facts about the Greater Yamhill Watershed:

  • 529,510 acres, ranging from the crest of the Coast Range to the Willamette River.
  • Roughly 70% of the GYW lies within Yamhill County
    • Most of the remaining in Polk County. Small portions of the watershed are within Washington, Lincoln, and Tillamook Counties.
  • There are ten incorporated cities and towns in the watershed:

  • McMinnville
  • Newberg
  • Yamhill
  • Willamina
  • Lafayette
  • Carlton
  • Sheridan
  • Dayton
  • Amity
  • Dundee

The Greater Yamhill Watershed Council’s service area includes eight sub-watersheds:

  • North Yamhill River
  • Willamina Creek
  • Upper South Yamhill River
  • Mill Creek
  • Salt Creek
  • South Yamhill River/Deer Creek
  • Yamhill River
  • Chehalem Creek*
    • Chehalem Creek Watershed includes Lambert Slough, a tributary to the Willamette River.