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
Snohomish7Blackmans Lake11/12/2024Anatoxin-a<MDL0.010NoViewHill Park BeachBLACSNOH132_24_468
Snohomish7Blackmans Lake11/12/2024Microcystin<MDL0.150NoViewHill Park BeachBLACSNOH132_24_468
Snohomish7Blackmans Lake11/12/2024Saxitoxin<MDL0.020NoViewHill Park BeachBLACSNOH132_24_468
Snohomish7Blackmans Lake10/28/2024Anatoxin-a<MDL0.010NoViewHill parkBLACSNOH132_24_451
Snohomish7Blackmans Lake10/28/2024Microcystin8.7900.300YesViewHill parkBLACSNOH132_24_451
Snohomish7Blackmans Lake07/18/2024Anatoxin-a0.0110.010NoNoHill ParkBLACSNOH132_24_085
Snohomish7Blackmans Lake07/18/2024Cylindrospermopsin<MDL0.025NoNoHill ParkBLACSNOH132_24_085
Snohomish7Blackmans Lake07/18/2024Microcystin<MDL0.150NoNoHill ParkBLACSNOH132_24_085
Snohomish7Blackmans Lake07/18/2024Saxitoxin<MDL0.022NoNoHill ParkBLACSNOH132_24_085
Snohomish7Blackmans Lake09/07/2023Anatoxin-a0.0100.010NoNoBoat launchBLACSNOH132_23_253
Snohomish7Blackmans Lake09/07/2023Microcystin0.9580.150NoNoBoat launchBLACSNOH132_23_253
Snohomish7Blackmans Lake12/01/2022Anatoxin-a<MDL0.010NoViewHill ParkBLACSNOH132_22_474
Snohomish7Blackmans Lake12/01/2022Microcystin<MDL0.150NoViewHill ParkBLACSNOH132_22_474
Snohomish7Blackmans Lake11/14/2022Anatoxin-a<MDL0.010NoViewBoat launch BLACSNOH132_22_464
Snohomish7Blackmans Lake11/14/2022Microcystin0.9320.150NoViewBoat launch BLACSNOH132_22_464
Snohomish7Blackmans Lake10/03/2022Anatoxin-a<MDL0.010NoViewBoat launchBLACSNOH132_22_363
Snohomish7Blackmans Lake10/03/2022Microcystin0.1510.150NoViewBoat launchBLACSNOH132_22_363
Snohomish7Blackmans Lake09/12/2022Anatoxin-a<MDL0.165NoViewHill Park shoreBLACSNOH132_22_305
Snohomish7Blackmans Lake09/12/2022Microcystin0.1520.150NoViewHill Park shoreBLACSNOH132_22_305
Snohomish7Blackmans Lake08/29/2022Anatoxin-a0.0120.010NoViewboat launchBLACSNOH132_22_260
Snohomish7Blackmans Lake08/29/2022Microcystin0.1840.150NoViewboat launchBLACSNOH132_22_260
Snohomish7Blackmans Lake08/08/2022Anatoxin-a0.0170.010NoViewBoat launchBLACSNOH132_22_160
Snohomish7Blackmans Lake08/08/2022Microcystin<MDL0.150NoViewBoat launchBLACSNOH132_22_160
Snohomish7Blackmans Lake07/24/2022Anatoxin-a0.0200.010NoViewcanalBLACSNOH132_22_117
Snohomish7Blackmans Lake07/24/2022Anatoxin-a<MDL0.010NoViewcanalBLACSNOH132_22_116
Snohomish7Blackmans Lake07/24/2022Cylindrospermopsin<MDL0.025NoViewcanalBLACSNOH132_22_116
Snohomish7Blackmans Lake07/24/2022Cylindrospermopsin<MDL0.025NoViewcanalBLACSNOH132_22_117
Snohomish7Blackmans Lake07/24/2022Microcystin<MDL0.150NoViewcanalBLACSNOH132_22_117
Snohomish7Blackmans Lake07/24/2022Microcystin<MDL0.150NoViewcanalBLACSNOH132_22_116
Snohomish7Blackmans Lake07/24/2022Saxitoxin<MDL0.020NoViewcanalBLACSNOH132_22_116
Snohomish7Blackmans Lake07/24/2022Saxitoxin<MDL0.020NoViewcanalBLACSNOH132_22_117
Snohomish7Blackmans Lake10/18/2021Anatoxin-a<MDL0.010NoViewboat launchBLACSNOH132_21_521
Snohomish7Blackmans Lake10/18/2021Cylindrospermopsin<MDL0.025NoViewboat launchBLACSNOH132_21_521
Snohomish7Blackmans Lake10/18/2021Microcystin6.2600.150NoViewboat launchBLACSNOH132_21_521
Snohomish7Blackmans Lake10/18/2021Saxitoxin<MDL0.020NoViewboat launchBLACSNOH132_21_521
Snohomish7Blackmans Lake10/26/2020Anatoxin-a<MDL0.010NoViewBoat launchBLACSNOH132_20_492
Snohomish7Blackmans Lake10/26/2020Microcystin21.6000.150YesViewBoat launchBLACSNOH132_20_492
Snohomish7Blackmans Lake09/29/2020Anatoxin-a<MDL0.010NoViewBoat launchBLACSNOH132_20_442
Snohomish7Blackmans Lake09/29/2020Microcystin3.8600.150NoViewBoat launchBLACSNOH132_20_442
Snohomish7Blackmans Lake09/16/2020Anatoxin-a<MDL0.010NoViewboat launchBLACSNOH132_20_384
Snohomish7Blackmans Lake09/16/2020Microcystin3.1200.150NoViewboat launchBLACSNOH132_20_384
Snohomish7Blackmans Lake08/03/2020Anatoxin-a0.0120.010NoViewHill ParkBLACSNOH132_20_193
Snohomish7Blackmans Lake08/03/2020Cylindrospermopsin<MDL0.025NoViewHill ParkBLACSNOH132_20_193
Snohomish7Blackmans Lake08/03/2020Microcystin0.1980.150NoViewHill ParkBLACSNOH132_20_193
Snohomish7Blackmans Lake08/03/2020Saxitoxin<MDL0.020NoViewHill ParkBLACSNOH132_20_193
Snohomish7Blackmans Lake08/15/2019Anatoxin-a<MDL0.010NoNo BLACSNOH132_19_158
Snohomish7Blackmans Lake08/15/2019Cylindrospermopsin<MDL0.025NoNo BLACSNOH132_19_158
Snohomish7Blackmans Lake08/15/2019Microcystin0.4590.150NoNo BLACSNOH132_19_158
Snohomish7Blackmans Lake08/15/2019Saxitoxin<MDL0.020NoNo BLACSNOH132_19_158
Snohomish7Blackmans Lake08/06/2019Anatoxin-a0.0250.010NoNo BALLSNOH132_19_125
Snohomish7Blackmans Lake08/06/2019Cylindrospermopsin<MDL0.025NoNo BALLSNOH132_19_125
Snohomish7Blackmans Lake08/06/2019Microcystin2.2300.150NoNo BALLSNOH132_19_125
Snohomish7Blackmans Lake08/01/2018Anatoxin-a<MDL0.010NoView BLACSNOH132_18_123
Snohomish7Blackmans Lake08/01/2018Cylindrospermopsin<MDL0.025NoView BLACSNOH132_18_123
Snohomish7Blackmans Lake08/01/2018Microcystin0.3140.150NoView BLACSNOH132_18_123
Snohomish7Blackmans Lake08/01/2018Saxitoxin<MDL0.020NoView BLACSNOH132_18_123
Snohomish7Blackmans Lake10/31/2017Anatoxin-a<MDL0.010NoNo BLACSNOH132_17_335
Snohomish7Blackmans Lake10/31/2017Microcystin10.1000.150YesNo BLACSNOH132_17_335
Snohomish7Blackmans Lake09/27/2016Anatoxin-a0.0210.010NoNo BLASNOH132_16_256
Snohomish7Blackmans Lake09/27/2016Microcystin0.2000.160NoNo BLASNOH132_16_256
Snohomish7Blackmans Lake09/14/2016Anatoxin-a0.0350.010NoNo  
Snohomish7Blackmans Lake09/14/2016Microcystin<MDL0.160NoNo  
Snohomish7Blackmans Lake08/23/2016Anatoxin-a0.0140.010NoNo BLACSNOH132_16_169
Snohomish7Blackmans Lake08/23/2016Microcystin<MDL0.200NoNo BLACSNOH132_16_169
Snohomish7Blackmans Lake08/15/2016Anatoxin-a<MDL0.010NoNo BLACSNOH132_16_157
Snohomish7Blackmans Lake08/15/2016Microcystin0.4290.200NoNo BLACSNOH132_16_157
Snohomish7Blackmans Lake08/02/2016Anatoxin-a0.0140.010NoView BLACSNOH132_16_128
Snohomish7Blackmans Lake08/02/2016Microcystin<MDL0.200NoView BLACSNOH132_16_128
Snohomish7Blackmans Lake08/02/2016Saxitoxin<MDL0.020NoView BLACSNOH132_16_128
Snohomish7Blackmans Lake10/23/2011Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake10/23/2011Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake10/09/2011Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake10/09/2011Microcystin0.0520.050NoNo BLACSNOH132
Snohomish7Blackmans Lake09/25/2011Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake09/25/2011Microcystin0.0580.050NoNo BLACSNOH132
Snohomish7Blackmans Lake09/11/2011Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake09/11/2011Microcystin0.0510.050NoNo BLACSNOH132
Snohomish7Blackmans Lake08/21/2011Anatoxin-a0.0320.019NoNo BLACSNOH132
Snohomish7Blackmans Lake08/21/2011Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake08/07/2011Anatoxin-a0.0240.019NoNo BLACSNOH132
Snohomish7Blackmans Lake08/07/2011Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake07/24/2011Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake07/24/2011Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake07/10/2011Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake07/10/2011Microcystin0.0500.050NoNo BLACSNOH132
Snohomish7Blackmans Lake06/19/2011Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake06/19/2011Microcystin0.0610.050NoNo BLACSNOH132
Snohomish7Blackmans Lake06/05/2011Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake06/05/2011Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake10/25/2010Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake10/25/2010Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake10/11/2010Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake10/11/2010Microcystin2.7700.050NoNo BLACSNOH132
Snohomish7Blackmans Lake09/27/2010Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake09/27/2010Microcystin0.0630.050NoNo BLACSNOH132
Snohomish7Blackmans Lake09/12/2010Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake09/12/2010Microcystin0.0720.050NoNo BLACSNOH132
Snohomish7Blackmans Lake08/23/2010Anatoxin-a0.0240.019NoNo BLACSNOH132
Snohomish7Blackmans Lake08/23/2010Microcystin0.0560.050NoNo BLACSNOH132
Snohomish7Blackmans Lake08/08/2010Anatoxin-a0.0230.019NoNo BLACSNOH132
Snohomish7Blackmans Lake08/08/2010Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake07/25/2010Anatoxin-a0.0420.019NoNo BLACSNOH132
Snohomish7Blackmans Lake07/25/2010Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake07/11/2010Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake07/11/2010Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake06/20/2010Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake06/20/2010Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake06/06/2010Anatoxin-a<MDL0.019NoNo BLACSNOH132
Snohomish7Blackmans Lake06/06/2010Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake10/19/2009Anatoxin-a<MDL0.150NoNo BLACSNOH132
Snohomish7Blackmans Lake10/19/2009Microcystin0.5420.050NoNo BLACSNOH132
Snohomish7Blackmans Lake10/04/2009Anatoxin-a<MDL0.012NoNo BLACSNOH132
Snohomish7Blackmans Lake10/04/2009Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake09/20/2009Anatoxin-a<MDL0.006NoNo BLACSNOH132
Snohomish7Blackmans Lake09/20/2009Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake09/07/2009Anatoxin-a<MDL0.012NoNo BLACSNOH132
Snohomish7Blackmans Lake09/07/2009Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake08/23/2009Anatoxin-a<MDL0.004NoNo BLACSNOH132
Snohomish7Blackmans Lake08/23/2009Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake08/09/2009Anatoxin-a<MDL0.006NoNo BLACSNOH132
Snohomish7Blackmans Lake08/09/2009Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake07/26/2009Anatoxin-a<MDL0.006NoNo BLACSNOH132
Snohomish7Blackmans Lake07/26/2009Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake07/12/2009Anatoxin-a<MDL0.004NoNo BLACSNOH132
Snohomish7Blackmans Lake07/12/2009Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake06/28/2009Anatoxin-a<MDL0.004NoNo BLACSNOH132
Snohomish7Blackmans Lake06/28/2009Microcystin<MDL0.050NoNo BLACSNOH132
Snohomish7Blackmans Lake06/14/2009Anatoxin-a<MDL0.003NoNo BLACSNOH132
Snohomish7Blackmans Lake06/14/2009Microcystin<MDL0.050NoNo BLACSNOH132

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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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