Warning issued for blue-green algae at lake
BALLINA Shire Council has issued a warning for blue-green algae at Lake Ainsworth.
Posting on Facebook, the council said environmental health officers had noticed blue green algae scums at the lake on Tuesday.
"This does not prohibit use but users should avoid contact with scums, which are concentrated areas of algae," the council said.
"Our Environmental Health Officers continue to monitor the Lake."
It is the second warning for the lake in the past month.
On September 21 the council advised that blue green algae levels were increasing.
Restrictions on swimming in the lake are not implemented until an "amber alert mode", which means algal concentrations are between 5000 and 50,000 cells/mL or the biovolume of all cyanobacteria is between 0.4 and 4mm3/L.
At this alert level the council will investigate the causes and increased sampling of algae should be undertaken.
"Red level action mode" is put in place when >50,000 cells of Microcystis aeruginosa are present or a biovolume of all toxin producing cyanobacteria exceeds 4 mm3/L or if the total of all cyanobacteria (toxic and non toxic) exceeds 10 mm3/L or scums are present for long periods.
At Red Mode, local and health authorities are contacted to assess risks to recreational users and appropriate measures should be taken to warn water users. Water should not be used for primary recreation.
The council says lake users should note any signage at the site and should report any sign of algae which may appear like a green paint spill on the surface of the water.
Phone the Development and Environmental Health Group on 6686 1210. To report algal blooms after hours phone 6626 6954.