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Puget Sound Salmon Health

Green/Duwamish River Basin

Salmon health indicators and environmental conditions for the Green/Duwamish River watershed in Central Sound. Area: 1,945 km².

Threatened

Chinook Returns (2024)

5.6kfish
up

All Species (2024)

8.6kfish

Watershed Area

1,945km²

Chinook Returns — Green/Duwamish River

2015 – 2024 · Annual estimated spawner counts

From 2010 to 2024, estimates increased by 170%. Most recent (2024): 6k fish. Range across period: 993–10k fish.

Estimated Chinook salmon returning to spawn each year based on WDFW spawner surveys. Chinook are the primary focus of recovery efforts and the species most important for tribal subsistence and cultural practices.

Source: WDFW Salmonid Population Indicators (SPI) — data.wa.gov · Refreshed Feb 21, 2026

View data as table
Chinook Returns — Green/Duwamish River — tabular data
YearValue (fish)
20102k
2011993
20123k
20132k
20143k
20154k
201610k
20178k
20187k
20193k
20204k
20213k
20226k
20232k
20246k

Returns by Species

Chinook

From 2010 to 2024, estimates increased by 170%. Most recent (2024): 6k fish. Range across period: 993–10k fish.
View data as table
Chinook Returns — tabular data
YearValue (fish)
20102k
2011993
20123k
20132k
20143k
20154k
201610k
20178k
20187k
20193k
20204k
20213k
20226k
20232k
20246k

Coho

From 2010 to 2024, estimates increased by 7%. Most recent (2024): 3k fish. Range across period: 67–5k fish.
View data as table
Coho Returns — tabular data
YearValue (fish)
20103k
20113k
20124k
20135k
20143k
2015619
20163k
2017469
20181k
2019774
20201k
20212k
202267
20231k
20243k

Chum

No data available for this selection.

Pink

No data available for this selection.

Sockeye

No data available for this selection.

Steelhead

No data available for this selection.

Environmental Conditions

Annual Water Temperature

From 2015 to 2024, estimates decreased by 9%. Most recent (2024): 8.3 °C. Range across period: 7.3–9.1 °C.

Annual median water temperature across active USGS monitoring stations in Puget Sound. Temperatures above 18°C cause physiological stress for adult salmon.

Source: USGS NWIS Statistics Service — annual median across 4 stations

View data as table
Annual Water Temperature — tabular data
YearValue (°C)
20159.1
20169
20177.7
20188.4
20198.4
20208.3
20218.3
20227.3
20238.8
20248.3

Annual Stream Discharge

From 2015 to 2024, estimates decreased by 22%. Most recent (2024): 287 cfs. Range across period: 279–480 cfs.

Annual median stream discharge across active USGS gauging stations in Puget Sound. Low flow years reduce spawning habitat and concentrate contaminants.

Source: USGS NWIS Statistics Service — annual median across 5 stations

View data as table
Annual Stream Discharge — tabular data
YearValue (cfs)
2015368
2016480
2017445
2018362
2019279
2020462
2021408
2022357
2023282
2024287

Restoration & Stewardship

Habitat restoration, hatchery programs, and monitoring projects are active across the Green/Duwamish River watershed. Tribal nations hold treaty-protected fishing rights and co-manage salmon populations under the Boldt Decision.

View Stewardship Projects →