A worker pumps algae into a treatment reservoir at Chaohu Lake in Hefei
A worker pumps blue-green algae into a treatment reservoir at Chaohu Lake in Hefei, Anhui province July 23, 2012.
But it's anyone's guess why the toxic algae that can cause illness and skin irritation has appeared so early in the season in Wasi Lake in Chisholm, about 30 kilometres southeast of North Bay.