Surface Water Management Division
Lake Ketchum is located two miles north of the City of Stanwood. It is 24 acres in size with an average depth of 3.7 meters. The watershed for the lake is 352 acres and is about 41% developed. There is a public boat launch on the south shore. Gas powered boats are not permitted.
Photo courtesy of Chris Sandys
Water Quality Information
Lake Ketchum has low water clarity, extremely high phosphorus levels, severe algal blooms, and dense aquatic plants. Although the lake provides valuable recreation and aesthetic enjoyment, excess algae and aquatic plants impair the use of the lake at times. Farm runoff and nutrient recycling within the lake must be controlled to restore the health of the lake.
A comprehensive Snohomish County State of the Lakes Report was produced in 2003 and includes a specific section on Lake Ketchum. Individual lake updates to this report are provided each year as new data are collected. In 1997 a lake restoration plan was also developed for Lake Ketchum.
Snohomish County Surface Water Management (SWM) together with volunteer lake-monitors have been collecting water quality data for Lake Ketchum since 1994. Current and historical lake water quality data are available online in SWM's interactive Water Quality Database.
What is Being Done to Help Lake Ketchum
During 2011 and 2012, the Snohomish County Surface Water Management Division is working with citizens and lake experts to develop a plan to improve water quality and control algae in Lake Ketchum. This project is partially funded by a grant from the Washington State Department of Ecology. Find out more about this project and future work to help improve the water quality at Lake Ketchum.
Lake Ketchum Toxic Algae Monitoring
Lake Ketchum has been monitored since 2008 for potentially toxic algae blooms that typically occur in the summer and fall. The following are links to information on the sampling projects and the most recent test results.
Lake Ketchum Maps
- Bathymetric Map - this map shows contour lines of equal depth similar to a topographic map. Public access sites are also indicated on each map when applicable.
- Aerial Photo - 2007 aerial photos of the lake with relevant features such as public access sites and nearby roads.
- Watershed Map - this map shows the boundary of the Lake Ketchum watershed. A watershed is the land area that drains into the lake.
Lake Ketchum Resources
Gene Williams, Senior Planner, 425-388-3464 extension 4563
Marisa Burghdoff, Water Quality Specialist, 425-388-3464 extension 4639
Jen Oden, Water Quality Specialist, 425-388-3464 extension 4352
Some documents are in pdf format. To read these files you'll need to have Adobe Acrobat Reader installed on your computer.