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
Snohomish7Howard Lake11/18/2025Anatoxin-a<MDL0.010NoNoBoat LaunchHOWASNOH017_25_503
Snohomish7Howard Lake11/18/2025Cylindrospermopsin<MDL0.025NoNoBoat LaunchHOWASNOH017_25_503
Snohomish7Howard Lake11/18/2025Microcystin1.9300.300NoNoBoat LaunchHOWASNOH017_25_503
Snohomish7Howard Lake11/18/2025Saxitoxin<MDL0.022NoNoBoat LaunchHOWASNOH017_25_503
Snohomish7Howard Lake10/22/2025Anatoxin-a<MDL0.010NoNoBoat LaunchHOWASNOH017_25_468
Snohomish7Howard Lake10/22/2025Cylindrospermopsin<MDL0.025NoNoBoat LaunchHOWASNOH017_25_468
Snohomish7Howard Lake10/22/2025Microcystin0.3670.300NoNoBoat LaunchHOWASNOH017_25_468
Snohomish7Howard Lake10/22/2025Saxitoxin<MDL0.022NoNoBoat LaunchHOWASNOH017_25_468
Snohomish7Howard Lake05/10/2021Anatoxin-a0.2200.010NoNoboat launchHOWASNOH017_21_033
Snohomish7Howard Lake05/10/2021Cylindrospermopsin<MDL0.025NoNoboat launchHOWASNOH017_21_033
Snohomish7Howard Lake05/10/2021Microcystin0.3070.150NoNoboat launchHOWASNOH017_21_033
Snohomish7Howard Lake05/10/2021Saxitoxin<MDL0.020NoNoboat launchHOWASNOH017_21_033
Snohomish7Howard Lake04/21/2020Anatoxin-a0.1450.010NoViewboat launchHOWASNOH017_20_029
Snohomish7Howard Lake04/21/2020Cylindrospermopsin<MDL0.025NoViewboat launchHOWASNOH017_20_029
Snohomish7Howard Lake04/21/2020Microcystin0.2070.150NoViewboat launchHOWASNOH017_20_029
Snohomish7Howard Lake04/21/2020Saxitoxin<MDL0.020NoViewboat launchHOWASNOH017_20_029
Snohomish7Howard Lake08/14/2017Anatoxin-a<MDL0.010NoNo HOWASNOH017_17-183
Snohomish7Howard Lake08/14/2017Microcystin0.3330.150NoNo HOWASNOH017_17-183
Snohomish7Howard Lake07/10/2017Anatoxin-a0.0150.010NoView HOWASNOH107_17_127
Snohomish7Howard Lake07/10/2017Microcystin56.1000.150YesView HOWASNOH107_17_127
Snohomish7Howard Lake06/01/2017Anatoxin-a0.0270.010NoNo HOWASNOH017_17_072
Snohomish7Howard Lake06/01/2017Microcystin0.2270.150NoNo HOWASNOH017_17_072
Snohomish7Howard Lake03/13/2017Anatoxin-a<MDL0.010NoNo HOWASNOH017_17_002
Snohomish7Howard Lake03/13/2017Microcystin<MDL0.200NoNo HOWASNOH017_17_002
Snohomish7Howard Lake01/09/2017Anatoxin-a<MDL0.010NoNo HOWASNOH017_17_001
Snohomish7Howard Lake01/09/2017Microcystin<MDL0.200NoNo HOWASNOH017_17_001
Snohomish7Howard Lake11/07/2016Anatoxin-a<MDL0.010NoNo HOWASNOH017_16_331
Snohomish7Howard Lake11/07/2016Microcystin<MDL0.200NoNo HOWASNOH017_16_331
Snohomish7Howard Lake09/27/2016Anatoxin-a<MDL0.010NoNo HOWASNOH017_16_255
Snohomish7Howard Lake09/27/2016Microcystin0.9000.160NoNo HOWASNOH017_16_255
Snohomish7Howard Lake09/10/2016Anatoxin-a<MDL0.010NoNo HowaSnoh017_16_206
Snohomish7Howard Lake09/10/2016Microcystin1.5800.200NoNo HowaSnoh017_16_206
Snohomish7Howard Lake07/26/2016Anatoxin-a<MDL0.010NoView HOWASNOH017_16_117
Snohomish7Howard Lake07/26/2016Microcystin1.4600.200NoView HOWASNOH017_16_117
Snohomish7Howard Lake06/06/2016Anatoxin-a<MDL0.010NoNo HOWASNOH017_16_075
Snohomish7Howard Lake06/06/2016Microcystin<MDL0.200NoNo HOWASNOH017_16_075
Snohomish7Howard Lake05/24/2016Anatoxin-a0.1340.010NoNo HowaSnoh017_16_062
Snohomish7Howard Lake05/24/2016SaxitoxinNA0.020NoNo HowaSnoh017_16_062
Snohomish7Howard Lake05/13/2016Anatoxin-a0.1120.010NoView HOWASNOH017_16_057
Snohomish7Howard Lake05/13/2016Microcystin<MDL0.160NoView HOWASNOH017_16_057
Snohomish7Howard Lake04/27/2016Anatoxin-a0.9220.010NoView HOWASNOH017_16_047
Snohomish7Howard Lake04/27/2016Microcystin<MDL0.160NoView HOWASNOH017_16_047
Snohomish7Howard Lake08/24/2015Microcystin<MDL0.160NoView HOWASNOH017_15_329
Snohomish7Howard Lake03/18/2015Anatoxin-a<MDL0.010NoView HOWASNOH15_066
Snohomish7Howard Lake03/18/2015Microcystin0.2300.160NoView HOWASNOH15_066
Snohomish7Howard Lake03/18/2015Saxitoxin0.0250.020NoView HOWASNOH15_066
Snohomish7Howard Lake03/10/2015Anatoxin-a<MDL0.010NoNo HOWASNOH15_061
Snohomish7Howard Lake03/10/2015Cylindrospermopsin<MDL0.100NoNo HOWASNOH15_061
Snohomish7Howard Lake03/10/2015Microcystin0.2210.160NoNo HOWASNOH15_061
Snohomish7Howard Lake03/10/2015Saxitoxin0.0270.020NoNo HOWASNOH15_061
Snohomish7Howard Lake02/24/2015Anatoxin-a<MDL0.010NoNo HOWASNOH15_049
Snohomish7Howard Lake02/24/2015Cylindrospermopsin<MDL0.100NoNo HOWASNOH15_049
Snohomish7Howard Lake02/24/2015Microcystin0.3060.160NoNo HOWASNOH15_049
Snohomish7Howard Lake02/24/2015Saxitoxin<MDL0.020NoNo HOWASNOH15_049
Snohomish7Howard Lake02/17/2015anatoxin-a0.0200.010NoNo HOWASNOH15-040
Snohomish7Howard Lake02/17/2015microcystin0.2000.160NoNo HOWASNOH15-040
Snohomish7Howard Lake11/14/2013Anatoxin-a<MDL0.010NoNo HOWASNOH13_269
Snohomish7Howard Lake11/14/2013Microcystin1.8800.160NoNo HOWASNOH13_269
Snohomish7Howard Lake11/04/2013Microcystin2.1000.160NoNo HOWASNOH13_255
Snohomish7Howard Lake10/29/2013Microcystin20.6000.160YesNo HOWASNOH13_239
Snohomish7Howard Lake11/13/2012Anatoxin-a0.0200.019NoNo  
Snohomish7Howard Lake11/13/2012Microcystin0.5260.050NoNo  
Snohomish7Howard Lake09/04/2012Microcystin0.2570.050NoView  
Snohomish7Howard Lake08/28/2012Microcystin2700.0000.050YesView  
Snohomish7Howard Lake07/16/2012Anatoxin-a<MDL0.019NoNo  
Snohomish7Howard Lake07/16/2012Microcystin105.0000.050YesNo  
Snohomish7Howard Lake11/15/2011Microcystin2.3700.050NoView  
Snohomish7Howard Lake11/08/2011Microcystin<MDL0.050NoView  
Snohomish7Howard Lake11/01/2011Microcystin0.9650.050NoView  
Snohomish7Howard Lake10/24/2011Microcystin1.5500.050NoView  
Snohomish7Howard Lake10/17/2011Microcystin0.7290.050NoView  
Snohomish7Howard Lake10/12/2011Microcystin0.5610.050NoView  
Snohomish7Howard Lake10/06/2011Anatoxin-a<MDL0.019NoView  
Snohomish7Howard Lake10/06/2011Microcystin56.3000.050YesView  
Snohomish7Howard Lake09/30/2011Anatoxin-a<MDL0.019NoView  
Snohomish7Howard Lake09/30/2011Microcystin12.1000.050YesView  

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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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