Snohomish River Basin
Salmon health indicators and environmental conditions for the Snohomish River watershed in Central Sound. Area: 4,851 km².
Chinook Returns — Snohomish River
2015 – 2024 · Annual estimated spawner counts
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
| Year | Value (fish) |
|---|---|
| 2010 | 4k |
| 2011 | 2k |
| 2012 | 5k |
| 2013 | 3k |
| 2014 | 4k |
| 2015 | 4k |
| 2016 | 5k |
| 2017 | 6k |
| 2018 | 4k |
| 2019 | 2k |
| 2020 | 4k |
| 2021 | 2k |
| 2022 | 3k |
| 2023 | 2k |
Returns by Species
Chinook
View data as table
| Year | Value (fish) |
|---|---|
| 2010 | 4k |
| 2011 | 2k |
| 2012 | 5k |
| 2013 | 3k |
| 2014 | 4k |
| 2015 | 4k |
| 2016 | 5k |
| 2017 | 6k |
| 2018 | 4k |
| 2019 | 2k |
| 2020 | 4k |
| 2021 | 2k |
| 2022 | 3k |
| 2023 | 2k |
Coho
View data as table
| Year | Value (fish) |
|---|---|
| 2010 | 58k |
| 2011 | 139k |
| 2012 | 151k |
| 2013 | 147k |
| 2014 | 58k |
| 2015 | 19k |
| 2016 | 57k |
| 2017 | 22k |
| 2018 | 68k |
| 2019 | 40k |
| 2020 | 50k |
| 2021 | 97k |
| 2022 | 83k |
| 2023 | 63k |
| 2024 | 74k |
Chum
No data available for this selection.
Pink
View data as table
| Year | Value (fish) |
|---|---|
| 2010 | 24 |
| 2011 | 433k |
| 2013 | 1.9M |
| 2014 | 46 |
| 2015 | 389k |
| 2016 | 11 |
| 2017 | 57k |
| 2019 | 596k |
| 2021 | 753k |
Sockeye
No data available for this selection.
Steelhead
No data available for this selection.
Environmental Conditions
Annual Water Temperature
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
| Year | Value (°C) |
|---|---|
| 2015 | 9.1 |
| 2016 | 9 |
| 2017 | 7.7 |
| 2018 | 8.4 |
| 2019 | 8.4 |
| 2020 | 8.3 |
| 2021 | 8.3 |
| 2022 | 7.3 |
| 2023 | 8.8 |
| 2024 | 8.3 |
Annual Stream Discharge
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
| Year | Value (cfs) |
|---|---|
| 2015 | 368 |
| 2016 | 480 |
| 2017 | 445 |
| 2018 | 362 |
| 2019 | 279 |
| 2020 | 462 |
| 2021 | 408 |
| 2022 | 357 |
| 2023 | 282 |
| 2024 | 287 |
Restoration & Stewardship
Habitat restoration, hatchery programs, and monitoring projects are active across the Snohomish River watershed. Tribal nations hold treaty-protected fishing rights and co-manage salmon populations under the Boldt Decision.
View Stewardship Projects →