As the temperature has continued to rise over the past three days, the blue-green algae has gathered at the western end of Taihui Lake, which sits on the border of East China's Jiangsu and Zhejiang provinces, just 11 km from Gonghu water plant, the main water source for Wuxi, Jiangsu.

And as the mercury climbs above 30 C, the thick blanket of foul-smelling algae in the 2,400-sq-km freshwater lake - the country's third largest - will expand rapidly, experts from the Wuxi agriculture and forestry bureau said.