$name - King County

Green Lake Duck Island Launch A734_GM21 only cyanotoxins

For algal toxin data please visit the State Toxic Algae web page and follow the “Find Lake” menu.

Please select a site and a year

Sample Date	Temperature (°C)	Temperature (°F)	Included in Bacteria Geomean Calculation?	Daily Average Bacteria
08/04/2020	23.0	73.4	No	not sampled
07/28/2020	23.0	73.4	No	not sampled
07/21/2020	23.0	73.4	No	not sampled
07/14/2020	20.0	68.0	No	not sampled
07/07/2020	20.0	68.0	No	not sampled
06/29/2020	20.0	68.0	No	not sampled
06/23/2020	21.0	69.8	No	not sampled
06/16/2020	18.0	64.4	No	not sampled
06/09/2020	18.0	64.4	No	not sampled
06/02/2020	18.0	64.4	No	not sampled
05/26/2020	17.0	62.6	No	not sampled
05/19/2020	18.0	64.4	No	not sampled
05/12/2020	19.0	66.2	No	not sampled

Table Legend

Cell Color	Bacteria Value	Concern Level
	Individual day <= 200 CFU/100 ml	Low Concern - safe for swimming
	Individual day > 200 & <= 1000 CFU/100 ml	Moderate Concern – still safe for swimming
	Individual day > 1000 CFU/100 ml or geometric mean > 200 CFU/100 ml	High Concern – probable closure. For more information see Beach Closure Protocol

NOTE: Beach closure and reopening decisions are made by Public Health – Seattle & King County. Decisions are based on these results plus additional information about beach conditions, and may not always match the concern levels shown here.

Redirecting to NWToxicAlgae site...

NOTE: Duck Island Launch is only monitored for algal toxins, not fecal coliform bacteria.