The Green-Duwamish River flows 93 miles from the Cascade Mountains to Elliott Bay through rural, agricultural, suburban, urban, and industrial land. The river is an important ecological, cultural, and economic resource in the region for people, plants, and wildlife. The river provides critical habitat for endangered salmon, which are important food supply for Orca whales.  

What’s the problem? 

Over the last 150 years, many native trees and shrubs have been removed from the banks of the Green-Duwamish River and its tributaries. The river is frequently exposed to direct sun, heating the water. Higher water temperatures create conditions that are unhealthy and sometimes lethal for our native salmon species, including the endangered and culturally-important Chinook salmon. The lack of trees and shrubs has also resulted in fewer insects that feed birds, salmon, and other wildlife and a lack of  wood to create complex habitat for fish. 

Without tree cover, the river heats up as it travels through the Green River Valley creating unhealthy conditions for salmon.

The River Needs Trees

Planting and maintaining trees and shrubs along the water’s edge benefits not only salmon, but the health of our community. We need more trees and shrubs along the river to keep it healthy, cool, and clean for people and wildlife. 

A healthy shoreline of trees and shrubs:

  • Keeps the river healthy for wildlife.
  • Filters pollutants from the air and capture rainwater to reduce stormwater runoff to keep the river water clean.
  • Increases water infiltration and storage in the watershed, improving summertime flows in the river.
  • Provides people with needed shade on a hot summer day, fresh air, and contributes to overall health and well-being.
  • Creates more inviting places for outdoor recreation and a change of scenery every season.
  • Creates economic benefits for businesses, including increased land value, reducing landscaping costs, and increasing employee retention.
  • Helps neighborhoods stay cool, healthy, beautiful, and thriving.  
  • Creates positive ripple effects for the whole region: from helping salmon upstream to the orcas downstream, and your community right here!  

Trees keep the Green-Duwamish River cool and clean for people and wildlife.

Green Duwamish Revegetation

Green Duwamish Revegetation is a coordinated group of agencies and non-governmental organizations working to increase vegetation along the Green Duwamish River and its tributaries to benefit fish, wildlife, and the community. Partners are working throughout the Green Duwamish watershed on projects to remove invasive species, plant native trees and shrubs, and improve habitat for fish and wildlife. 

See where we’re working.

Learn about the progress we’ve made.

Contact Us