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
Pierce11Ohop Lake08/27/2024Anatoxin-a<MDL0.010NoNoBoat launch OHOPPIER048_24_242
Pierce11Ohop Lake08/27/2024Microcystin<MDL0.150NoNoBoat launch OHOPPIER048_24_242
Pierce11Ohop Lake08/13/2024Anatoxin-a<MDL0.010NoNoMiddle of lakeOHOPPIER048_24_168
Pierce11Ohop Lake08/13/2024Microcystin17.3000.300YesNoMiddle of lakeOHOPPIER048_24_168
Pierce11Ohop Lake10/17/2023Anatoxin-a<MDL0.010NoView OHOPPIER048_23-388
Pierce11Ohop Lake10/17/2023Microcystin0.2360.150NoView OHOPPIER048_23-388
Pierce11Ohop Lake09/18/2023Anatoxin-a<MDL0.010NoNoBoat launchOHOPPIER048_23_299
Pierce11Ohop Lake09/18/2023Microcystin0.8810.150NoNoBoat launchOHOPPIER048_23_299
Pierce11Ohop Lake08/28/2023Anatoxin-a<MDL0.010NoNoBoat launchOHOPPIER048_23_235
Pierce11Ohop Lake08/28/2023Microcystin3.2600.150NoNoBoat launchOHOPPIER048_23_235
Pierce11Ohop Lake08/29/2022Anatoxin-a<MDL0.010NoView OHOPPIER048_22-266
Pierce11Ohop Lake08/29/2022Microcystin<MDL0.150NoView OHOPPIER048_22-266
Pierce11Ohop Lake08/15/2022Anatoxin-a<MDL0.010NoViewboat launchOHOPPIER048_22_205
Pierce11Ohop Lake08/15/2022Microcystin<MDL0.150NoViewboat launchOHOPPIER048_22_205
Pierce11Ohop Lake08/08/2022Anatoxin-a0.0520.010NoViewboat launchOHOPPIER048_22_173
Pierce11Ohop Lake08/08/2022Microcystin<MDL0.150NoViewboat launchOHOPPIER048_22_173
Pierce11Ohop Lake08/01/2022Anatoxin-a<MDL0.010NoViewboat launchOHOPPIER048_22_147
Pierce11Ohop Lake08/01/2022Microcystin<MDL0.150NoViewboat launchOHOPPIER048_22_147
Pierce11Ohop Lake07/25/2022Anatoxin-a<MDL0.010NoNoboat launchOHOPPIER048_22_124
Pierce11Ohop Lake07/25/2022Anatoxin-a<MDL0.010NoNoboat launchOHOPPIER048_22_124
Pierce11Ohop Lake07/25/2022Microcystin<MDL0.150NoNoboat launchOHOPPIER048_22_124
Pierce11Ohop Lake07/25/2022Microcystin<MDL0.150NoNoboat launchOHOPPIER048_22_124
Pierce11Ohop Lake07/05/2022Anatoxin-a<MDL0.010NoView OHOPPIER048_22-074
Pierce11Ohop Lake07/05/2022Microcystin<MDL0.150NoView OHOPPIER048_22-074
Pierce11Ohop Lake09/20/2021Anatoxin-a<MDL0.010NoViewEast of Boat launch OHOPPIER048_21_413
Pierce11Ohop Lake09/20/2021Microcystin3.4300.150NoViewEast of Boat launch OHOPPIER048_21_413
Pierce11Ohop Lake09/13/2021Anatoxin-a<MDL0.010NoView002OHOPPIER048_21_372
Pierce11Ohop Lake09/13/2021Microcystin0.9580.150NoView002OHOPPIER048_21_372
Pierce11Ohop Lake09/07/2021Anatoxin-a<MDL0.010NoViewBoat launchOHOPPIER048_21_345
Pierce11Ohop Lake09/07/2021Microcystin8.9600.150YesViewBoat launchOHOPPIER048_21_345
Pierce11Ohop Lake12/07/2020Anatoxin-a<MDL0.010NoView OHOPPIER048
Pierce11Ohop Lake12/07/2020Microcystin0.6030.150NoView OHOPPIER048
Pierce11Ohop Lake11/02/2020Microcystin0.3930.150NoView OHOPPIER048
Pierce11Ohop Lake10/26/2020Microcystin2.7400.150NoViewMile post 1OHOPPIER048_20_496
Pierce11Ohop Lake10/19/2020Microcystin2.7900.150NoViewPullout; Ohop 3OHOPPIER048_20_477
Pierce11Ohop Lake10/05/2020Microcystin0.2970.150NoViewBoat launchOHOPPIER048_20_455
Pierce11Ohop Lake09/28/2020Anatoxin-a<MDL0.010NoViewboat launchOHOPPIER048_20_431
Pierce11Ohop Lake09/28/2020Microcystin4.5200.150NoViewboat launchOHOPPIER048_20_431
Pierce11Ohop Lake09/21/2020Microcystin3.6000.150NoViewBoat launchOHOPPIER048_20_402
Pierce11Ohop Lake08/03/2020Anatoxin-a0.4170.010NoViewBoat launchOHOPPIER048_20_212
Pierce11Ohop Lake08/03/2020Microcystin0.2280.150NoViewBoat launchOHOPPIER048_20_212
Pierce11Ohop Lake11/14/2019Anatoxin-a<MDL0.010NoNo OHOPPIER048
Pierce11Ohop Lake11/14/2019Microcystin2.6200.150NoNo OHOPPIER048
Pierce11Ohop Lake10/28/2019Anatoxin-a<MDL0.010NoNo OHOPPIER048_19_437
Pierce11Ohop Lake10/28/2019Microcystin9.6600.150YesNo OHOPPIER048_19_437
Pierce11Ohop Lake10/14/2019Anatoxin-a<MDL0.010NoNo OHOPPIER048_19_401
Pierce11Ohop Lake10/14/2019Microcystin1.1400.150NoNo OHOPPIER048_19_401
Pierce11Ohop Lake09/25/2019Anatoxin-a<MDL0.010NoNo OHOPPIER048_19_335
Pierce11Ohop Lake09/25/2019Microcystin15.2000.150YesNo OHOPPIER048_19_335
Pierce11Ohop Lake09/03/2019Anatoxin-a<MDL0.010NoNo OHOPPIER048_19_236
Pierce11Ohop Lake09/03/2019Microcystin2.9800.150NoNo OHOPPIER048_19_236
Pierce11Ohop Lake08/28/2019Anatoxin-a<MDL0.010NoNo OHOPPIER048_19_213
Pierce11Ohop Lake08/28/2019Microcystin1.1000.150NoNo OHOPPIER048_19_213
Pierce11Ohop Lake08/15/2019Anatoxin-a0.0120.010NoNo OHOPPIER048_19_159
Pierce11Ohop Lake08/15/2019Microcystin0.1550.150NoNo OHOPPIER048_19_159
Pierce11Ohop Lake10/24/2017Anatoxin-a<MDL0.010NoNo OHOPPIER048_17_323
Pierce11Ohop Lake10/24/2017Microcystin0.3660.150NoNo OHOPPIER048_17_323
Pierce11Ohop Lake05/31/2017Anatoxin-a0.0240.010NoNo OHOPPIER048_17_070
Pierce11Ohop Lake05/31/2017Microcystin3.6000.160NoNo OHOPPIER048_17_070
Pierce11Ohop Lake09/28/2015Microcystin4.8400.160NoNo OHOPPIER048_15_426
Pierce11Ohop Lake08/26/2015Anatoxin-a<MDL0.010NoNo OHOPPIER048_15_332
Pierce11Ohop Lake08/26/2015Microcystin23.3000.160YesNo OHOPPIER048_15_332
Pierce11Ohop Lake07/30/2015Anatoxin-a0.0260.010NoNo OHOPPIER048_15_244
Pierce11Ohop Lake07/30/2015Microcystin19.7000.160YesNo OHOPPIER048_15_244
Pierce11Ohop Lake07/16/2014Microcystin<MDL0.160NoView OHOPPIER14_095
Pierce11Ohop Lake07/16/2014Saxitoxin<MDL0.020NoView OHOPPIER14_095
Pierce11Ohop Lake09/11/2013Microcystin5.2500.160NoView OHOPIER13_121
Pierce11Ohop Lake08/21/2013Anatoxin-a<MDL0.010NoView OHOPPIER13_073
Pierce11Ohop Lake08/21/2013Microcystin0.4090.160NoView OHOPPIER13_073
Pierce11Ohop Lake08/01/2013Anatoxin-a0.0120.010NoView OHOPPIER13_040
Pierce11Ohop Lake08/01/2013Microcystin0.9050.160NoView OHOPPIER13_040
Pierce11Ohop Lake06/04/2013Anatoxin-a0.0170.010NoView OHOPPIER13_01
Pierce11Ohop Lake06/04/2013Microcystin0.3580.050NoView OHOPPIER13_01
Pierce11Ohop Lake11/07/2012Anatoxin-a0.1770.019NoNo  
Pierce11Ohop Lake11/07/2012Microcystin20.8000.050YesNo  
Pierce11Ohop Lake10/17/2012Anatoxin-a<MDL0.019NoView  
Pierce11Ohop Lake10/17/2012Microcystin9.1500.050YesView  
Pierce11Ohop Lake10/03/2012Anatoxin-a0.0200.019NoView  
Pierce11Ohop Lake10/03/2012Microcystin7.7600.160NoView  
Pierce11Ohop Lake10/24/2011Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake10/24/2011Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake10/10/2011Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake10/10/2011Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake09/26/2011Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake09/26/2011Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake09/12/2011Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake09/12/2011Microcystin0.7740.050NoNo OHOPPIER048
Pierce11Ohop Lake09/06/2011Anatoxin-a0.0340.019NoView  
Pierce11Ohop Lake09/06/2011Cylindrospermopsin<MDL0.100NoView  
Pierce11Ohop Lake09/06/2011Microcystin11.0000.050YesView  
Pierce11Ohop Lake09/06/2011Saxitoxin<MDL0.020NoView  
Pierce11Ohop Lake08/22/2011Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake08/22/2011Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake08/08/2011Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake08/08/2011Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake07/24/2011Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake07/24/2011Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake07/11/2011Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake07/11/2011Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake06/20/2011Anatoxin-a0.0270.019NoNo OHOPPIER048
Pierce11Ohop Lake06/20/2011Microcystin0.3050.050NoNo OHOPPIER048
Pierce11Ohop Lake06/06/2011Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake06/06/2011Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake10/25/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake10/25/2010Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake10/20/2010Microcystin0.6470.050NoView  
Pierce11Ohop Lake10/12/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake10/12/2010Microcystin2.1200.050NoNo OHOPPIER048
Pierce11Ohop Lake10/06/2010Microcystin4.2200.050NoView  
Pierce11Ohop Lake09/27/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake09/27/2010Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake09/22/2010Anatoxin-a<MDL0.019NoView  
Pierce11Ohop Lake09/22/2010Microcystin0.0560.050NoView  
Pierce11Ohop Lake09/13/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake09/13/2010Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake08/22/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake08/22/2010Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake08/09/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake08/09/2010Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake07/26/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake07/26/2010Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake07/11/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake07/11/2010Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake06/20/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake06/20/2010Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake06/06/2010Anatoxin-a<MDL0.019NoNo OHOPPIER048
Pierce11Ohop Lake06/06/2010Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake11/03/2009Microcystin3.6100.050NoNo  
Pierce11Ohop Lake10/27/2009Microcystin0.7330.050NoNo  
Pierce11Ohop Lake10/17/2009Anatoxin-a<MDL0.006NoNo OHOPPIER048
Pierce11Ohop Lake10/17/2009Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake10/08/2009Anatoxin-a<MDL0.130NoNo OHOPPIER048
Pierce11Ohop Lake10/08/2009Microcystin29.0000.050YesNo OHOPPIER048
Pierce11Ohop Lake10/04/2009Anatoxin-a<MDL0.012NoNo OHOPPIER048
Pierce11Ohop Lake10/04/2009Microcystin0.1570.050NoNo OHOPPIER048
Pierce11Ohop Lake09/28/2009Microcystin0.6360.050NoNo  
Pierce11Ohop Lake09/20/2009Anatoxin-a<MDL0.012NoNo OHOPPIER048
Pierce11Ohop Lake09/20/2009Microcystin0.0690.050NoNo OHOPPIER048
Pierce11Ohop Lake09/14/2009Microcystin8.0800.050YesNo  
Pierce11Ohop Lake09/14/2009Microcystin0.4490.050NoNo  
Pierce11Ohop Lake09/07/2009Anatoxin-a<MDL0.006NoNo OHOPPIER048
Pierce11Ohop Lake09/07/2009Microcystin0.0760.050NoNo OHOPPIER048
Pierce11Ohop Lake09/01/2009Microcystin0.4850.050NoNo  
Pierce11Ohop Lake08/23/2009Anatoxin-a<MDL0.006NoNo OHOPPIER048
Pierce11Ohop Lake08/23/2009Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake08/19/2009Microcystin0.3810.050NoNo  
Pierce11Ohop Lake08/09/2009Anatoxin-a<MDL0.012NoNo OHOPPIER048
Pierce11Ohop Lake08/09/2009Microcystin0.0580.050NoNo OHOPPIER048
Pierce11Ohop Lake07/26/2009Anatoxin-a<MDL0.006NoNo OHOPPIER048
Pierce11Ohop Lake07/26/2009Microcystin0.0510.050NoNo OHOPPIER048
Pierce11Ohop Lake07/13/2009Anatoxin-a<MDL0.006NoNo OHOPPIER048
Pierce11Ohop Lake07/13/2009Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake06/29/2009Anatoxin-a<MDL0.003NoNo OHOPPIER048
Pierce11Ohop Lake06/29/2009Microcystin<MDL0.050NoNo OHOPPIER048
Pierce11Ohop Lake06/14/2009Anatoxin-a<MDL0.003NoNo OHOPPIER048
Pierce11Ohop Lake06/14/2009Microcystin0.1460.050NoNo OHOPPIER048
Pierce11Ohop Lake12/01/2008Microcystin2.8300.050NoNo  
Pierce11Ohop Lake11/17/2008Microcystin1.2700.050NoNo  
Pierce11Ohop Lake11/03/2008Microcystin0.2000.050NoNo  
Pierce11Ohop Lake10/27/2008Microcystin6.1600.050NoNo  
Pierce11Ohop Lake10/14/2008Microcystin1.6000.050NoNo  
Pierce11Ohop Lake10/06/2008Microcystin92.0000.050YesNo  
Pierce11Ohop Lake09/29/2008Microcystin5.2700.050NoNo  
Pierce11Ohop Lake09/23/2008Microcystin57.6000.050YesNo  
Pierce11Ohop Lake09/16/2008Microcystin4620.0000.050YesNo  
Pierce11Ohop Lake09/16/2008Microcystin5.1200.050NoNo  
Pierce11Ohop Lake09/09/2008Microcystin44.0000.050YesNo  
Pierce11Ohop Lake09/03/2008Microcystin63.6000.050YesNo  
Pierce11Ohop Lake11/07/2007Microcystin<MDL0.050NoNo  

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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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