Lake Armstrong

Lake Armstrong is a 30.8 acre lake located 2.5 miles north of Arlington. It has an average depth of 15 feet and a maximum depth of 24 feet. The watershed, or the land area that drains into the lake, covers 434.4 acres and is mostly undeveloped. Lake Armstrong provides a serene setting with one of the least developed shorelines in the county.

Recreational Opportunities

  • Boat Launch
  • Boating (No gasoline-powered motors)
  • Fishing
  • Lake Access
There is a public boat launch on the south end of the lake off of Lake Armstrong Road as shown on the bathymetric maps below. Internal combustion motors are not allowed on Lake Armstrong - see Snohomish County Code Title 12 and the Parks and Recreation Boating Regulations for more information.

Fishing Information

The Washington Department of Fish and Wildlife (WDFW) maintains informational pages for each lake in Washington that include: fish stocking schedules, fishing prospect calendars, and boat launch information.

Connect with Your Lake Community

Lake Armstrong does not have a formal lake association. However, you may be able to connect with other lake area residents by looking for a Lake Armstrong community group on NextDoor or Facebook.

Lake Health and Additional Resources

As part of Snohomish County's Lake Management Program, County staff and volunteer lake monitors have been tracking the health of Lake Armstrong since 1992. 

Health Report Card

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In Depth Health Report

In Depth Lake Health Report

​For more historical information on Lake Armstrong please refer to the 2003 State of the Lakes Report.
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View maps of Lake Armstrong and the surrounding area, including the location of public access sites.

Watershed Map
Area that drains to the lake

Bathymetry Map
Depth contours of the lake

Aerial Bathymetry Map
Depth contours of the lake with satellite images
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