In central China's Wuhan, blue algae is threatening to choke one of the city's lakes. City water authorities have been forced to take urgent action to contain its proliferation.

Guanqiao Lake, also known as Miao lake, is one of the eight smaller lakes that constitute the East Lake in Wuhan. This is where the blue algae outbreak originated. For now, water authority workers have resorted to setting up sandbag barriers to stop the algae from spreading to the other lakes. But they say more sophisticated methods will be required.

Xiang Jiuhua, assistant to the chief engineer of Wuhan Water Authority, said, "We're going to use biological methods to remove the algae."

There were several blue algae outbreaks in the East Lake in the 1980s. Water authorities began stocking the lake with algae-eating fish, and no algae cases have been reported since 1985. Experts say the change of mineral composition of the water and the recent hot weather may have caused the algae to grow,tipping the delicate balance of the eco-system and endangering other species.