Blue-green algae has emerged on another of China's large inland lakes, threatening water supplies for millions of local farmers, an official said yesterday.
"The Dianchi Lake now looks like green paint," said a press officer with the government bureau in charge of the lake who would only give his surname, Zhao.
The massive freshwater lake lies near Kunming, the capital of Yunnan Province.
Zhao said the outbreak began last month and was thought to be caused by hot weather. However, he also said the lake has been badly polluted by industries and sewage discharge in recent years.
He said Dianchi is among the country's most polluted lakes and is similar in quality to Lake Tai, which last month also suffered an algae bloom that forced 5 million residents of the eastern city of Wuxi to drink and bathe with bottled water.
Foul-smelling algae outbreaks on Dianchi Lake have occurred every year since the 1990s, he said. This year's bloom seemed to cover a smaller area than in previous years, Zhao said, but was he unable to give specific measurements.
Yunnan's Life Express newspaper quoted a resident surnamed Zhang as saying the bloom was worse then in recent years.
The paper also quoted another resident, surnamed Li, who said the algae was deadly to aquatic life and very corrosive.
"Where there is algae, there is no fish or shrimp. Ship paint also peels off because of the algae," Li said.
Residents of Kunming mainly rely on a separate Zhangjiuhe reservoir for their drinking water, but Zhao said that factories and millions of farmers still use Dianchi's water for industrial use and for watering crops.
Officials were using boats equipped with pumps that push the lake water through filters to try to get rid of the bloom, Zhao said.