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
Thurston13Offutt Lake11/18/2025Anatoxin-a<MDL0.010NoNoPublic Boat LaunchOFFUTHUR063_25_505
Thurston13Offutt Lake11/18/2025Microcystin<MDL0.300NoNoPublic Boat LaunchOFFUTHUR063_25_505
Thurston13Offutt Lake11/12/2025Microcystin3.0100.300NoNoPublic boat launchOFFUTHUR063_25_494
Thurston13Offutt Lake11/04/2025Anatoxin-a<MDL0.010NoNoPublic Boat LaunchOFFUTHUR063_25_493
Thurston13Offutt Lake11/04/2025Microcystin153.0000.300YesNoPublic Boat LaunchOFFUTHUR063_25_493
Thurston13Offutt Lake10/29/2025Microcystin<MDL0.300NoNoPublic boat launchOFFUTHUR063_25_484
Thurston13Offutt Lake10/22/2025Anatoxin-a<MDL0.010NoNo OFFUTHUR063_25_471
Thurston13Offutt Lake10/22/2025Microcystin41.7000.300YesNo OFFUTHUR063_25_471
Thurston13Offutt Lake08/26/2025Anatoxin-a<MDL0.010NoNoPublic boat launchOFFUTHUR063_25_294
Thurston13Offutt Lake08/26/2025Microcystin0.9610.300NoNoPublic boat launchOFFUTHUR063_25_294
Thurston13Offutt Lake08/12/2025Anatoxin-a<MDL0.020NoNoPublic boat launchOFFUTHUR063_25_234
Thurston13Offutt Lake08/12/2025Microcystin0.5400.300NoNoPublic boat launchOFFUTHUR063_25_234
Thurston13Offutt Lake07/16/2025Anatoxin-a<MDL0.010NoNoPrivate residence, north side of lakeOFFUTHUR063_25_147
Thurston13Offutt Lake07/16/2025Cylindrospermopsin<MDL0.025NoNoPrivate residence, north side of lakeOFFUTHUR063_25_147
Thurston13Offutt Lake07/16/2025Microcystin0.6650.300NoNoPrivate residence, north side of lakeOFFUTHUR063_25_147
Thurston13Offutt Lake07/16/2025Saxitoxin<MDL0.022NoNoPrivate residence, north side of lakeOFFUTHUR063_25_147
Thurston13Offutt Lake10/24/2024Microcystin5.7500.300NoNoPublic Boat LaunchOFFUTHUR063_24_435
Thurston13Offutt Lake10/17/2024Microcystin0.5510.300NoViewPublic Boat LaunchOFFUTHUR063_24_413
Thurston13Offutt Lake10/10/2024Anatoxin-a<MDL0.010NoViewPublic Boat LaunchOFFUTHUR063_24_390
Thurston13Offutt Lake10/10/2024Microcystin30.0000.300YesViewPublic Boat LaunchOFFUTHUR063_24_390
Thurston13Offutt Lake08/22/2024Anatoxin-a<MDL0.010NoViewPublic Boat LaunchOFFUTHUR063_24_208
Thurston13Offutt Lake08/22/2024Cylindrospermopsin<MDL0.025NoViewPublic Boat LaunchOFFUTHUR063_24_208
Thurston13Offutt Lake08/22/2024Microcystin6.2200.300NoViewPublic Boat LaunchOFFUTHUR063_24_208
Thurston13Offutt Lake08/22/2024Saxitoxin<MDL0.022NoViewPublic Boat LaunchOFFUTHUR063_24_208
Thurston13Offutt Lake10/19/2023Anatoxin-a<MDL0.010NoViewNear boat launchOFFUTHUR063_23_390
Thurston13Offutt Lake10/19/2023Microcystin<MDL0.150NoViewNear boat launchOFFUTHUR063_23_390
Thurston13Offutt Lake10/17/2022Anatoxin-a<MDL0.010NoViewthroughout lakeOFFUTHUR063_22_407
Thurston13Offutt Lake10/17/2022Microcystin3.4100.150NoViewthroughout lakeOFFUTHUR063_22_407
Thurston13Offutt Lake08/03/2021Anatoxin-a0.0150.010NoViewWDFW boat launchOFFUTHUR063_21_198
Thurston13Offutt Lake08/03/2021Cylindrospermopsin<MDL0.025NoViewWDFW boat launchOFFUTHUR063_21_198
Thurston13Offutt Lake08/03/2021Microcystin0.4200.150NoViewWDFW boat launchOFFUTHUR063_21_198
Thurston13Offutt Lake08/03/2021Saxitoxin0.0370.020NoViewWDFW boat launchOFFUTHUR063_21_198
Thurston13Offutt Lake05/11/2021Anatoxin-a<MDL0.010NoViewWDFW boat launchOFFUTHUR063_21_034
Thurston13Offutt Lake05/11/2021Cylindrospermopsin<MDL0.025NoViewWDFW boat launchOFFUTHUR063_21_034
Thurston13Offutt Lake05/11/2021Microcystin0.1520.150NoViewWDFW boat launchOFFUTHUR063_21_034
Thurston13Offutt Lake05/11/2021Saxitoxin<MDL0.020NoViewWDFW boat launchOFFUTHUR063_21_034
Thurston13Offutt Lake10/20/2020Anatoxin-a<MDL0.010NoViewWDFW boat launchOFFUTHUR063_20_488
Thurston13Offutt Lake10/20/2020Cylindrospermopsin<MDL0.025NoViewWDFW boat launchOFFUTHUR063_20_488
Thurston13Offutt Lake10/20/2020Microcystin0.2100.150NoViewWDFW boat launchOFFUTHUR063_20_488
Thurston13Offutt Lake10/20/2020Saxitoxin0.0230.020NoViewWDFW boat launchOFFUTHUR063_20_488
Thurston13Offutt Lake10/24/2018Anatoxin-a<MDL0.010NoView OFFUTHUR063_18_348
Thurston13Offutt Lake10/24/2018Microcystin<MDL0.150NoView OFFUTHUR063_18_348
Thurston13Offutt Lake09/25/2018Anatoxin-a<MDL0.010NoView OFFUTHUR063_18_271
Thurston13Offutt Lake09/25/2018Microcystin2.0000.150NoView OFFUTHUR063_18_271
Thurston13Offutt Lake09/19/2018Anatoxin-a<MDL0.010NoView OFFUTHUR063_18_255
Thurston13Offutt Lake09/19/2018Microcystin0.2060.150NoView OFFUTHUR063_18_255
Thurston13Offutt Lake07/18/2018Anatoxin-a<MDL0.010NoView OFFUTHUR063_18_097
Thurston13Offutt Lake07/18/2018Anatoxin-a<MDL0.010NoView OFFUTHUR063_18_098
Thurston13Offutt Lake07/18/2018Microcystin<MDL0.150NoView OFFUTHUR063_18_098
Thurston13Offutt Lake07/18/2018Microcystin<MDL0.150NoView OFFUTHUR063_18_097
Thurston13Offutt Lake05/23/2018Anatoxin-a<MDL0.010NoView OFFUTHUR063_18_046
Thurston13Offutt Lake05/23/2018Cylindrospermopsin<MDL0.025NoView OFFUTHUR063_18_046
Thurston13Offutt Lake05/23/2018Microcystin0.3830.150NoView OFFUTHUR063_18_046
Thurston13Offutt Lake05/23/2018Saxitoxin<MDL0.020NoView OFFUTHUR063_18_046
Thurston13Offutt Lake12/19/2017Anatoxin-a<MDL0.010NoNo OFFUTHUR063
Thurston13Offutt Lake12/19/2017Microcystin<MDL0.150NoNo OFFUTHUR063
Thurston13Offutt Lake10/30/2017Anatoxin-a<MDL0.010NoNo OFFUTHUR063_17_329
Thurston13Offutt Lake10/30/2017Microcystin0.2490.150NoNo OFFUTHUR063_17_329
Thurston13Offutt Lake10/16/2017Anatoxin-a<MDL0.010NoNo OFFUTHUR063_17_305
Thurston13Offutt Lake10/16/2017Microcystin0.9470.150NoNo OFFUTHUR063_17_305
Thurston13Offutt Lake11/09/2011Microcystin70.5000.050YesView  
Thurston13Offutt Lake11/02/2011Microcystin1620.0000.050YesView  

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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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