Shared Strategy for Puget Sound
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Salmon Recovery Plan
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Meet the Salmon

Threatened species include Green/Duwamish River Summer/Fall Chinook and Newaukum Creek Summer/Fall Chinook. The watershed is also home to Fall chum, Coho and pink salmon, summer and winters steelhead, coastal cutthroat and bull trout, also listed as threatened.

Chum Salmon
Pink Salmon
Bull Trout
Salmon images courtesy of King County. Steelhead image courtesy of National Oceanic and Atmospheric Administration/Department of Commerce.
How Chinook Use the Watershed

The Middle Green River mainstem as well as portions of Newaukum Creek provide nearly all the spawning habitat and some rearing habitat in this watershed. Major groups of Chinook spawn from RM 25 through 61 in the Green River; this is considered one of the ten most important reaches to protect threatened Chinook in Puget Sound. Chinook also rely upon the Duwamish estuary for rearing and to make their transition from fresh to saltwater conditions (smoltification) before migrating out to the ocean.

Salmon and the Green/Duwamish Watershed



For more information about salmon recovery planning in this watershed, click here.

Click here to read this watershed's feedback summary.


Key Facts

Year 2000 population estimate is 583,692; 89% reside within the Urban Growth Area designated under the state Growth Management Act.

Projected population growth is 16% from 2000 to 2020; the fastest growth is expected in suburban cities and unincorporated areas south and southwest of Seattle.

Located entirely in King County, the watershed is home to 15 other jurisdictions, including the cities of Seattle, Renton, Kent, Auburn, SeaTac, Federal Way, Tukwila, Burien, Covington, Maple Valley and Enumclaw. The watershed also is the City of Tacoma’s water supply and is becoming interconnected with the regional water supply grid.

The planning area for the watershed under the state Watershed Management Act is all of Watershed Resource Inventory Area (WRIA) 9, and portions of WRIAs 8, 10, and 15.


This watershed starts high in the Cascade mountain range at the headwaters of the Green River. The upper third of the Green flows through forest land. After about thirty miles, it begins to meander through agricultural lands, small woodland lots, state and county parks, and small towns that rapidly become busy Seattle suburbs. The lands surrounding the river become more urban and more industrialized as we follow it downstream. The Green flows into the Duwamish River eleven miles from its mouth flanked by landscape that shifts from suburban to industrial as it approaches the waterways at the delta, where sports stadiums built on the former mudflat and giant shipping cranes welcome the Duwamish as it flows into Elliott Bay.

The Green/Duwamish and Central Puget Sound Watershed has 92 miles of marine shoreline, anchored by Elliott Bay to the north and Dumas Bay to the south on the mainland, and the shores of Vashon and Maury Islands.

Located at the downstream end of the Green River gorge, Flaming Geyser State Park is a popular take out point for rafters and kayakers enjoying whitewater adventures in the gorge. The park's namesake, the Flaming geyser, and its smaller companion, the Bubbling geyser are both unique and intriguing features. While only burning 6 to 10 inches high now, in its younger days it burned several feet high with gushes of fire and water. It was even featured on Ripley's Believe It or Not.

The Green River is usually one of the top ten steelhead rivers in Washington. It is also a top white water rafting river, containing Class IV and V rapids in the scenic Green River Gorge.

The Duwamish River, a key passage to the inland portions of the state, was a prime focus of heavy industrial development over the last century. The lower river’s meandering course through 9 miles of wetlands, tidal marshes and intertidal mudflats was straightened (channelized) and dredged down to 5 miles between 1900 and 1940 to provide shipping lanes and new land for Seattle’s burgeoning industrial and manufacturing district. Indeed the Duwamish embodies all the challenges facing Puget Sound salmon – growth pressures, shoreline alterations, combined sewer overflow, stormwater run-off, contaminated sediment, urbanization, industrial development and up-river habitat passage barriers and degradation from dams, agriculture and forestry. The Duwamish remains a river of major cultural importance to Native Americans.

Despite enduring tumultuous change in a short period of time the Duwamish and its sole remaining tributary, the Green River, still support substantial populations of naturally spawning and hatchery salmon as well as a heron rookery. The Green’s Bass Lake/wetland complex has the greatest bird species diversity of wetlands surveyed in King County. Local, state, federal and tribal governments, area businesses and environmental stewardship groups have demonstrated a sustained commitment to protect and restore salmon and the health of the watershed.

Major Policy or Actions Needed to Recover Salmon

Diverse Partners Aim to “Protect, Connect and Unlock” the Watershed’s Natural Potential
Since the late 1980s, half-a-dozen major collaborations have taken aim at restoring the Duwamish watershed, including the Lower Duwamish Superfund and Elliott Bay/Duwamish Restoration Program. Current collaborative restoration and protection efforts involve state, federal and local governments, including King County, Tacoma, and all 15 cities in the watersheds. Boeing and other area businesses and environmental groups also participate. Current goals to address habitat issues in support of salmon conservation and recovery are:

  • Protect currently functioning habitat primarily in the Middle Green River and the nearshore areas of Vashon/Maury Island.
  • Connect the Upper Green River by restoring fish passage at Howard Hanson Dam.
  • Ensure adequate juvenile salmon survival in the Lower Green River, Duwamish Estuary, and other nearshore areas. 

Restoring Access Above Howard Hanson Dam Would Connect High-quality Habitat
Howard Hanson Dam completely blocks passage of adult salmon and cuts off access to 45 percent of the stream miles historically available to migrating fish. The Army Corps of Engineers (Corps) and the City of Tacoma are working to restore access, which is expected to significantly open up the amount of available habitat for returning adult salmon and their offspring.

Partners Working to Provide More Water for Fish and People
Tacoma Public Utilities and the U.S. Corps of Engineers and other partners are sharing costs for developing the Additional Water Storage Project. The project will make more municipal water available for fast-growing cities in south King County and allow Howard Hanson Dam managers to improve flows for fish in the Middle and Lower Green River.

We’re Making Progress—Some Accomplishments

Strategic Habitat Restoration
Over 500 acres have been acquired by local governments for habitat protection and restoration purposes in the watershed since 1999. Most of this high quality habitat is in the Middle Green, a part of the watershed identified as essential to protect threatened Chinook. A portion of the 500 acres slated for restoration are in the Duwamish and will provide scarce rearing habitat for estuary-dependent juvenile Chinook. A multiple-year partnership among the local governments and the U.S. Army Corps of Engineers is in the $113 million construction phase. 45 major habitat restoration projects will be constructed over 20 years.

Successful Growth Management
Since the inception of the Growth Management Act, the dramatic increase in residential development in designated Urban Growth Areas within the watershed has been accompanied by decreases in residential development in rural and forest areas.

Flood Control and Habitat Improvements in the Floodplain
The Green River Flood Control Zone District routinely includes habitat improvements as part of flood facility repair and reconstruction. This includes placement of large woody debris, levee setbacks, and planting native riparian vegetation along the mainstem of the Lower Green River. King County’s Flood Hazard Reduction Plan is being updated to ensure compliance with Endangered Species Act mandates.

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