Lower Pilchuck River Assessment

In December 2018, Snohomish County Public Works Surface Water Management (SWM) completed a study of the changing conditions of the Lower Pilchuck River. See the final report of the Lower Pilchuck River Assessment (PDF) to learn more.


The Pilchuck River is home to approximately 1,000 riverside residents, several species of salmon, and countless other birds and animals. Over the past several years, this region has experienced some of its highest floods on record, causing property damage from flooding and erosion. Additionally, salmon numbers in the river have declined from historical levels. Three species of local salmon – Chinook, steelhead, and bull trout – are now listed as “threatened” on the Endangered Species List.

Study Area

The Lower Pilchuck River Assessment covers approximately 8.6 miles of the river between OK Mill Road and the end of the Pilchuck River where it connects with the Snohomish River.

SWM completed an assessment of Middle Pilchuck River – from the City of Snohomish Diversion dam to the OK Mill Road bridge – in 2011.


Next Steps

This final report, coupled with historic data on channel location and movement, enables SWM to take a look at how sediment is moving through the system, what changes have occurred in the river, and where potential restoration opportunities could be feasible. SWM will be identifying potential projects to address flooding and erosion concerns for landowners, and to improve fish habitat, within the Pilchuck River.

You Can Help 

Please contact Lisa Tario via email if you have ideas or information about locations for potential habitat improvement projects. If you are interested in planting trees or eradicating invasive species, such as knotweed, along the Pilchuck River, assistance and resources may be available to help fund this work.

Together we can make the Pilchuck River a healthier place for future generations of people and wildlife.