Lake Bosworth

Lake Bosworth is a 103.0 acres lake located three miles south of Granite Falls. It is a deep lake, with a maximum depth of 79 feet and an average depth of 35 feet. The watershed, or the land area that drains into the lake is 955.5 acres, and it is mostly undeveloped except for dense homes located around the the lake shore.

Recreational Opportunities

  • Boat Launch
  • Boating (No gasoline-powered motors)
  • Fishing
  • Restrooms/Sanicans
There is a Washington Department of Fish and Wildlife public boat launch on the northeast side of Lake Bosworth, 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 Bosworth does not have a formal lake association. However, you may be able to connect with other lake area residents by looking for a Lake Bosworth 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 Bosworth since 1990. 

Health Report Card

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In Depth Health Report

In Depth Lake Health Report

​For more historical information on Lake Bosworth please refer to the 2003 State of the Lakes Report.
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View maps of Lake Bosworth 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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