Detailed search for your lake

This database contains the most current toxicity data available. All instances of values above the recreational guidelines are kept as up to date as possible, but values below the guidelines may be somewhat delayed in entry.Since there is a lag time from the date of sample to the date of analysis, be sure to check the sample date when looking at data or before you use the lake. Remember to use caution and avoid scums. "When in doubt, stay out!"

Your local jurisdiction may have more specific information about your lake. Questions? Contact toxicalgae at Department of Ecology.

If a lake is not listed, it has not been tested for toxic algae through the Ecology program.

The pins on the map represent the center of small lakes, regardless of where the sample was taken. To find more precise location information, download the toxin data and click the "view scum info" link. That is where specific sampling location information will be if it was provided. On larger lakes, (such as Lake Washington, Moses Lake and Potholes) pins represent the location of the sample if provided.

Toxin:
CountyWRIA NumberSiteCollect DateParameterToxin Conc. (µg/L)MDL (µg/L)Above State GuidelineAdditional InformationSample LocationEcology Tracking Number
King9Lake Fenwick08/17/2025Anatoxin-a<MDL0.010NoNoSoutheast shallow bayFENWKING310_25_256
King9Lake Fenwick08/17/2025Microcystin<MDL0.300NoNoSoutheast shallow bayFENWKING310_25_256
King9Lake Fenwick10/29/2023Anatoxin-a<MDL0.165NoNo FENWKING310-23_427
King9Lake Fenwick10/29/2023Microcystin1.5800.150NoNo FENWKING310-23_427
King9Lake Fenwick08/21/2022Anatoxin-a0.0310.010NoViewshorelineFENWKING310_22_237
King9Lake Fenwick08/21/2022Microcystin0.8330.150NoViewshorelineFENWKING310_22_237
King9Lake Fenwick09/23/2021Anatoxin-a<MDL0.010NoViewfishing platformFENWKING310_21_428
King9Lake Fenwick09/23/2021Microcystin<MDL0.150NoViewfishing platformFENWKING310_21_428
King9Lake Fenwick10/27/2020Anatoxin-a<MDL0.010NoViewWalking PlatformFENWKING310_20_502
King9Lake Fenwick10/27/2020Microcystin1.6100.150NoViewWalking PlatformFENWKING310_20_502
King9Lake Fenwick10/26/2020Anatoxin-a<MDL0.010NoViewboardwalk shoreFENWKING310_20_501
King9Lake Fenwick10/26/2020Microcystin0.6070.150NoViewboardwalk shoreFENWKING310_20_501
King9Lake Fenwick10/21/2020Anatoxin-a<MDL0.010NoViewboat launchFENWKING310_20_489
King9Lake Fenwick10/21/2020Microcystin1.0400.150NoViewboat launchFENWKING310_20_489
King9Lake Fenwick08/18/2020Anatoxin-a<MDL0.010NoView FENWKING310_20_275
King9Lake Fenwick08/18/2020Microcystin2.9200.150NoView FENWKING310_20_275
King9Lake Fenwick11/04/2019Anatoxin-a<MDL0.010NoNo FENWKING310_19_441
King9Lake Fenwick11/04/2019Microcystin0.4900.150NoNo FENWKING310_19_441
King9Lake Fenwick10/28/2019Microcystin0.5030.150NoNo FENWKING310_19_424
King9Lake Fenwick10/21/2019Anatoxin-a<MDL0.010NoView FENWKING310_19_409
King9Lake Fenwick10/21/2019Microcystin3.2500.150NoView FENWKING310_19_409
King9Lake Fenwick10/09/2019Anatoxin-a<MDL0.010NoNo FENWKING310_19_386
King9Lake Fenwick10/09/2019Microcystin7.3000.150NoNo FENWKING310_19_386
King9Lake Fenwick10/02/2019Anatoxin-a<MDL0.010NoNo FENWKING310_19_368
King9Lake Fenwick10/02/2019Microcystin49.0000.150YesNo FENWKING310_19_368
King9Lake Fenwick09/25/2019Anatoxin-a<MDL0.010NoNo FENWKING310_19_330
King9Lake Fenwick09/25/2019Microcystin1.8800.150NoNo FENWKING310_19_330
King9Lake Fenwick09/12/2019Anatoxin-a<MDL0.010NoNo FENWKING310_19_288
King9Lake Fenwick09/12/2019Microcystin3.8700.150NoNo FENWKING310_19_288
King9Lake Fenwick11/14/2018Microcystin0.2320.150NoView FENWKING310_18_370
King9Lake Fenwick11/05/2018Microcystin3.4900.150NoView FENWKING310_18_365
King9Lake Fenwick10/26/2018Anatoxin-a<MDL0.010NoView FENWKING310_18_351
King9Lake Fenwick10/26/2018Microcystin32.0000.150YesView FENWKING310_18_351
King9Lake Fenwick08/27/2018Anatoxin-a0.0860.010NoView FENWKING310_18_194
King9Lake Fenwick08/27/2018Microcystin2.3700.150NoView FENWKING310_18_194
King9Lake Fenwick08/20/2018Anatoxin-a<MDL0.010NoView FENWKING310_18_171
King9Lake Fenwick08/20/2018Microcystin3.0000.150NoView FENWKING310_18_171
King9Lake Fenwick08/13/2018Anatoxin-a<MDL0.010NoNo FENWKING310_18_158
King9Lake Fenwick08/13/2018Cylindrospermopsin<MDL0.025NoNo FENWKING310_18_158
King9Lake Fenwick08/13/2018Microcystin104.0000.150YesNo FENWKING310_18_158
King9Lake Fenwick08/13/2018Saxitoxin<MDL0.020NoNo FENWKING310_18_158
King9Lake Fenwick10/16/2017Anatoxin-a<MDL0.010NoNo FENWKING000_17_302
King9Lake Fenwick10/16/2017Microcystin3.5200.150NoNo FENWKING000_17_302

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As of 6/26/2018 the format of the toxin and phytoplankton export has changed. A unique identification number has been added to each site.

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