About Us

The Greater Yamhill Watershed Council (GYWC), formed in 1995 by the Yamhill and Polk County Commissioners, is a non-regulatory, community-based nonprofit organization dedicated to empowering our local communities to be good stewards of the lands, waters, fish and wildlife in the Yamhill and Chehalem Valleys (map of the Greater Yamhill Watershed).  

Over the last 22 years, the GYWC has served as a local leader in monitoring water quality and fish habitat in local streams and rivers, increasing community awareness of and engagement in healthy watershed projects, and assisting landowners and stakeholders in developing partnerships and projects that improve water quality and habitat for fish and wildlife. 

The GYWC is part of a network of over 70 Oregon watershed councils formed across the state since the mid-1990’s, and has been awarded competitive Operational Capacity grants through the State’s Oregon Watershed Enhancement Board (OWEB) since the Council’s formation.

The GYWC is governed by a Board of Directors composed of local stakeholders and supported by a diverse network of Partners representing public, private, and tribal interests.  The Board of Directors and Partners provide guidance and support for the Watershed Council’s Executive Director who works to organize partnerships and secure diverse funding for projects that improve water quality and habitat for fish and wildlife.

Cozine Creek

Stay Connected

Subscribe to our Friends of Cozine E-Newsletter for updates on activities in the Cozine Creek watershed, including project tours, educational presentations and guest speakers, community potlucks, and opportunities to volunteer for habitat restoration and water quality monitoring projects.


Get Involved in Upcoming Events


Community Presentation
Improving Creekside Habitat

Tuesday, February 6th, 6pm- 7pm
McMinnville Library Carnegie Room
225 NW Adams Street, McMinnville, OR 97128

No RSVP Required

Learn about common and priority invasive weeds, researched effectiveness of weed control methods, the best native plants to use along streams, and grant funding available for public and private landowers to improve creekside habitat along Cozine Creek.


Cozine Creek Work Party
Native Tree/Shrub Planting & Invasive Ivy Removal @ Ash Meadows Park

Saturday, February 3rd, 10am - 1pm
& Sunday, February 11th, 9am - 12pm
Ash Meadows City Park
748 South Agee Street, McMinnville, OR 97128

Get Involved! RSVP Online

Join us for two mornings of food and fun to improve water quality and habitat along Cozine Creek at Ash Meadows Park. We will be planting more than ~150 trees and shrubs, installing deer browse protector tubes, and removing invasive english ivy from trees.

All ages welcome, under 18 yrs of age if accompanied by a guardian

You Bring: Water bottle and dress for weather, wet, and mud.

GYWC Will Provide: Tools, Gloves, Refreshments, and a Pizza Lunch.


Cozine Creek Work Party
Invasive Ivy Removal @ Brockwood Avenue

Saturday, February 24th, 10am - 1pm
533 SW Brockwood Ave, McMinnville, OR 97128

Get Involved! RSVP Online

Join us for a morning of food and fun to improve water quality and habitat along Cozine Creek along Brockwood Avenue. We will done boots and waders to cut invasive ivy out of trees in an Oregon Oak & Ash Urban Floodplain Forest along Cozine Creek.

Ages 18+ 

You Bring: Water bottle and dress for weather, wet, and mud. Bring waders or boots if you have them, or borrow a pair from the GYWC.

GYWC Will Provide: Tools, Gloves, Refreshments, and a Pizza Lunch.

Water Quality Monitoring 

General Water Quality

Stay tuned. We have applied for grant funding in early 2018 to to update our water quality database and produce a Cozine Creek Water Quality Report and to share the results with Cozine Creek stakeholder groups and the general community. If funded, work will begin in May 2018 and a water quality report will available by November 2018 at the latest.

Pesticide Stewardship Partnership (PSP)

  • Statewide PSP Program Summary, 2013-2015 (PDF 1.6 Mb)
  • Yamhill PSP Program Summary, 2015, Updated in 2018 for Contact Info (PDF 0.8 Mb)
  • 2017, Cozine Monitoring Results are pending approval by the State. Check back here ~ March / April 2018.
  • 2016, Cozine Monitoring Results (Excel) (PDF)
  • 2015, Cozine Monitoring Results (Excel) (PDF)
  • 2014, Cozine Monitoring Results (Excel) (PDF)
  • 2013, Cozine Monitoring Results (Excel) (PDF)
  • 2012, Cozine Monitoring Results (Excel) (PDF) Pending Retrieval from State Database
  • 2011, Cozine Monitoring Results (Excel) (PDF) Pending Retrieval from State Database


Learn More About Cozine Creek & Friends of Cozine

With the headwaters of its main branch flowing down from the coastal foothills near S.W. Peavine Road, about five miles west of the city, Cozine Creek cuts through seven miles of forests, farm fields and urban development before joining the South Yamhill River near S.E. Dayton Avenue. Another 14 miles of named and unnamed tributaries enter the main branch from the north, south and west. 

Prior to European settlement in the Willamette Valley in the early to mid 1800s, the lands encompassing the more than 11-square-mile drainage area of Cozine Creek and its tributaries
were dominated by wide open expanses of grass prairies, edible wildflowers and scatterings of mature oak trees, with majestic boughs stretching out limbs to form umbrella-shaped crowns. And along the active floodplains, dense woodlands shaded the waters of Cozine Creek with stands of oak, ash, big leaf maple and cottonwood.
Cozine Creek has been a focus area for the Greater Yamhill Watershed Council (GYWC) since 1995.  As a result of historic and current land use practices, the biological, physical, chemical, and social characteristics of Cozine Creek have been altered and even degraded. State-funded water quality monitoring projects conducted by the Greater Yamhill Watershed Council (GYWC) have identified that Cozine Creek is water quality impaired by multiple pollutants, including stream temperatures that are too hot for fish, dissolved oxygen levels that are too low for general aquatic life, and summertime E. Coli concentrations that have exceeded limits for human recreational water contact. 

Yet despite these concerns, life can be surprisingly resilient in Cozine Creek. And if you look in the right places, you’ll be surprised to discover how much you may have been missing: beaver, fish, crawdads, blue heron, bald eagles, and even fields of flowering camas lilies and ancient oak trees.

We have an abundance of opportunities to improve the health and beauty of Cozine Creek. The time to care for Cozine is now. In the coming months, with funding and support from the City of McMinnville, Linfield College, and the Yamhill Soil & Water Conservation District, the GYWC will be conducting a number of outreach activities to help lift Cozine Creek back into our community awareness, including habitat project tours, social potlucks, weed control and native planting workshops, as well as opportunities for volunteering for trash cleanups and habitat restoration work parties.

The GYWC will also be reaching out to landowners and stakeholders to find those who are interested in weed control and native planting projects along their properties. Since 2002, the GYWC and our partners have secured more than $45,000 in state funding and local matching dollars for projects to enhance habitat along Cozine Creek. With the support of our community and Cozine Creek landowners, we are working to accelerate the pace of these efforts, and to meet our goal of securing another $45,000 for projects by June 2019.

To stay tuned on upcoming Cozine Creek outreach and volunteer opportunities, please sign up for our Friends of Cozine E-Newsletter  or contact us at info@gywc.org.

Or if you are an interested Cozine Creek landowner and would like to learn more about funding and partnership opportunities for controlling weeds and planting natives, please contact Luke Westphal at 503-474-1047 or luke@gywc.org.