Find comprehensive services, data and information related to lakes in King County, Washington.
To offer a suggestion or report an error on the King County lakes website, please contact Fred Bentler, webmaster.
Lake services and information
Look up individual lakes in King County
Lake water quality
- Swimming beach water quality and temperature
Find out about bacteria pollution levels and health risks at swimming beaches on lake Sammamish, Lake Washington, Pine Lake, Fivemile Lake, and Lake Wilderness.
- Graphs and data for major lakes
- Graphs and data for small lakes
- Combined sewer overflow real-time map - Seattle area
- Environmental indicators for freshwater environment
Learn about the condition of King County’s lakes, key factors influencing their condition, King County actions, and how you can help.
- Sediment quality evaluation in Lake Sammamish, Lake Union, and Lake Washington
Report of chemical and biological substances, their distribution and toxicity, and benthic communities at various sample sites.
- Streams monitoring
Keeping watch for pollution in streams draining to Lake Washington, Lake Sammamish and the Green/Duwamish River.
- Metropolitan Water Pollution Abatement Advisory Committee (MWPAAC)
Created by state law, the MWPAAC advisites the King County Executive and Council on reducing water pollution.
King County small lakes water quality map
This color lake map displays lakes across King County in different colors depending on their water quality. Lakes may be:
- hypereutrophic - very poor water quality
- eutrophic - poor water quality
- mesotrophic - moderate water quality
- oligotrophic - good water quality
The map also depicts easily readable lake names, rivers and streams and ciities as of March, 2003. Map size is 11" x 17" with landscape orientation. File format is Adobe Acrobat version 5. File size is 1.28 Mb.
- Hydrography - interactive map
Note: this link will open a new browser window
Zoom in to view and query GIS datasets including lakes and streams in King County, drainage areas, King County wetlands inventory, National wetlands inventory, and display aerial photos and USGS topographic map images.
- King County lakes map (734 Kb Adobe Acrobat)
This color map includes cities as of December, 1999; lakes, lake names in western King County, rivers, and streams.
Lake resources, guides and references
Learn about King County's program to protect shorelines, promote public access, and establish priorities for shoreline uses for the county's large lakes, rivers and Puget Sound.
- History of King County's regional wastewater treatment utility
Read how our region worked to keep our lakes and Puget Sound clean and healthy, including the early days of sewage treatment and disposal in King County, the birth of Metro and development of regional facilities to process the waste produced by our metropolitan area.
- The birth of Metro
- Lake Washington story
A discussion about the value of Lake Washington, its past pollution problems and subsequent efforts to clean up the lake.
- Lake Sammamish story
An overview of Lake Sammamish and its value to people and wildlife, the lake's past pollution problems and subsequent efforts to keep the lake clean.
Be a lake volunteer - how you can help:
- Environmental laboratory
Collects samples from lakes, rivers and marine waters, biosolids application sites, industries and wastewater treatment plants, and analyzes samples in one of several labs including trace metals, organics, conventionals, microbiology and aquatic toxicology labs.
- Aquatic plants
Find out how to identify plants in your lake including noxious aquatic weeds, and learn how to help manage aquatic plants.
- Volunteer event calendar
Join us in stenciling stormdrains, restoring fish and wildlife habitat, and other lake related activities.