A pollution-linked algae bloom has reappeared in China's third-largest lake, prompting renewed fears for the drinking water supplies of millions of residents, state press said Tuesday.

Taihu Lake in eastern China has seen a re-emergence of algae growth that last year forced authorities to cut water supplies to 2.3 million residents of the nearby city of Wuxi last May, the People's Daily said.

The lake in Jiangsu province, long celebrated through Chinese history as one of the country's most scenic bodies of water, has been massively polluted by the dumping of sewage and industrial and agricultural waste.

The water crisis last year made it a symbol of China's nationwide problem of deteriorating water quality, with even Premier Wen Jiabao publicly calling for the lake to be cleaned up.

Drinking supplies were cut off for days last year after residents complained of foul water coming out of their taps, causing a crisis that sparked panic hoarding of water.

Authorities now fear that could happen again in coming months, the People's Daily, the Communist Party's main mouthpiece, said in a story posted on its website.

Conditions were ripe for a recurrence of the problem, caused by a combination of pollution and warm weather, the paper quoted Lin Zexin, vice head of the Taihu Administrative Bureau, as saying.

"Cleaning up Taihu Lake's pollution will not be a short-term effort, but will be a protracted battle," he said.

Taihu is China's third-largest freshwater lake, covering a surface area of some 2,340 square kilometers (about 900 square miles).

Algae blooms are common on many Chinese freshwater lakes and are chiefly caused by untreated sewage containing high concentrations of nitrogen, a main ingredient in detergents and fertilisers.

Like much of China's environment, water quality has suffered severely amid the nation's breakneck economic growth over the past two decades.

More than 70 percent of China's waterways and 90 percent of its underground water have been contaminated by pollution, according to government figures.