Blue Green Algae readings and what they mean

No Alert Level Triggered	GREEN LEVEL Surveillance Mode	AMBER LEVEL Alert Mode	RED LEVEL Action Mode
Cyanobacterial measurement
<500 cells/mL M.aeruginosa Biovolume <0.04 for the combined total of all cyanobacteria	500 to <5000 cells/mL M.aeruginosa Biovolume equivalent of >0.04 to <0.4 mm3/L for the combined total of all cyanobacteria	5000 to <50,000 cells/mL M.aeruginosa Biovolume equivalent of 0.4 to 4mm3/L for the combined total of all cyanobacteria where a toxic producer is dominant in the total biovolume OR 0.4 to < 10 mm3/L for the combined total of all cyanobacteria where known toxic producers are not present	10μg/L total microcystins OR 50,000 cells/mL - M.aeruginosa Biovolume equivalent of > 4mm3/L for the combined total of all cyanobacteria where known toxic producers are dominate in the total biovolume OR >10mm3/L for the combined total of all cyanobacteria where known toxic producers are not present OR Cyanobacteria scums are consistently present
Action Required
No restriction	No restriction. Routine monitoring to measure cyanobacterial levels. No Actions	No restriction. Increased sampling to enable risks to be more accurately assessed No Actions	CDC to provide warning that Lake is considered unsuitable for direct water contact activities including, swimming, bathing, kayaking. CDC to install signage "Lake Closed for Primary Contact Activities"

Skin and eye irritation with prolonged contact.
Gastrointestinal complaints (eg. vomiting, diarrhoea) from consumption of water.
Boiling water does not remove toxins.
Livestock including companion animals can be particularly susceptible to toxins produced by algae.

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